JPH08180126A - Bar code reading method and bar code reading device - Google Patents

Abstract

(57) [Summary] [Object] The present invention relates to a barcode reading method and apparatus applied to a POS system or the like, and when one barcode is divided into a plurality of portions and demodulated, the reading efficiency is lowered. The objective is to improve the reading rate and reduce the misreading rate. [Configuration] The reference number changing unit 15 sets and changes the reference number in the matching number determining unit 13 according to the reading state information of the barcode 1 from the reading state information acquiring unit 14, and the matching number determining unit 13 causes the barcode to be read. The number of coincidences in which the same data is continuously demodulated from 1 is detected,
When the number of times of matching reaches the reference number of times, the data demodulated from the barcode 1 is validated and the reading of the barcode 1 is completed.

Description

Detailed Description of the Invention

(Table of Contents) Industrial Application Field of the Prior Art (FIGS. 27 to 32) Problem to be Solved by the Invention Means for Solving the Problem (FIG. 1) Action (FIG. 1) Embodiment (a) Description of one embodiment (FIGS. 2 to 6) (b) Description of second embodiment (FIGS. 7 and 8) (c) Description of third embodiment (FIGS. 9 and 10) (d) Fourth embodiment Description of examples (FIGS. 11 to 13) (e) Description of fifth embodiment (FIGS. 14 to 18) (f) Description of sixth embodiment (FIGS. 19 to 21) (g) Description of seventh embodiment Description (FIGS. 22 and 23) (h) Description of the eighth embodiment (FIGS. 24 to 26) (i) Other effects of the invention

[0002]

The present invention relates to a supermarket,
POS system (Point Of
The present invention relates to a bar code reading method and a bar code reading device applied to a sales system (point of sale information management system) and the like.

[0003]

2. Description of the Related Art FIG. 27 is a block diagram showing the configuration of a general bar code reader (bar code reader). In FIG. 27, reference numeral 1 is a bar code printed on the surface of an article or the like. Code 1 is usually composed of a plurality of black bars (hereinafter referred to as black bars) and white bars (hereinafter referred to as white bars) alternately arranged, based on the width of each black bar and each white bar. Represents predetermined data.

2 is a laser beam L for the bar code 1.
2 is an optical system for irradiating 2 and receiving the reflected light R1 of the laser beam L2 reflected from the barcode 1. The optical system 2 is composed of a laser emitting section 3, a scanning mechanism 4 and a photoelectric conversion section 5. ing. Here, the laser emission unit 3 is configured to include a semiconductor laser that emits the laser beam L1.

The scanning mechanism 4 is composed of, for example, a polygon mirror rotated by a motor.
By reflecting the laser beam L1 from the laser emitting unit 3, the laser beam L1 is irradiated as a laser beam L2 toward a plurality of black bars and white bars forming the bar code 1, and the black bar of the bar code 1 It has the function of moving and scanning at a constant speed in the direction intersecting with the white bar.

The scanning mechanism 4 reflects the reflected light R1 of the laser beam L2 from the bar code 1 to the photoelectric conversion unit 5 as the reflected light R1 that moves with the scanning of the laser beam L2 as the reflected light R2. It also has a function of making it incident. Further, the photoelectric conversion unit 5 is configured to include a photoelectric conversion element such as a photodiode, and the reflected light R2 (optical input signal) received via the scanning mechanism 4 is converted into an electric signal according to the light amount thereof. It is converted into (analog value) and output.

On the other hand, in FIG. 27, 6 is a photoelectric conversion unit 5.
Is an A / D conversion unit for digitizing the electric signal from the photoelectric conversion unit 5, and the A / D conversion unit 6 digitizes the electric signal from the photoelectric conversion unit 5 so that each black bar forming the bar code 1 is formed. The signal is converted into a binarized signal of a corresponding black level signal and a white level signal corresponding to each white bar portion forming the barcode 1. As the binarized signal, the quantity of the reflected light R2 from each white bar portion is usually larger than the quantity of the reflected light R2 from each black bar portion. Low level signal
The level signal is obtained.

Reference numeral 7 is a bar width counter for counting the clock signal from the clock generator 8. The bar width counter 7 is a black level signal portion and a white level signal of the binarized signal from the A / D converter 6. A value corresponding to the time width of the portion, that is, the width of each black bar and each white bar of the actual barcode 1 is output as the count value of the clock signal.

Further, 9 is a memory for storing the bar width count value from the bar width counter 7, 10 is a CPU, and this CPU 10 has a bar width count value (for each black bar and each white bar) stored in the memory 9. It is for extracting and demodulating the predetermined data of the barcode 1 based on the value corresponding to the width). With the above-described configuration, the laser beam L1 emitted from the laser emission unit 3 is emitted as the laser beam L2 toward the black bar and the white bar of the barcode 1 by the scanning mechanism 4, and the black bar and the white bar of the barcode 1 are emitted. It is moved and scanned at a constant speed in the direction intersecting the bar.

A laser beam L emitted from the scanning mechanism 4
2 is the reflected light R1 which is scattered and reflected at the barcode 1 portion.
And reenters the scanning mechanism 4. The reflected light R1 moves by changing the reflection angle in accordance with the scanning movement of the laser beam L2, but is reflected by the polygon mirror constituting the scanning mechanism 4 and is thus arranged at a predetermined position as the reflected light R2. The light enters the photoelectric conversion element of the photoelectric conversion unit 5.

The photoelectric conversion unit 5 converts the reflected light R2 into an electric signal corresponding to the amount of light, and the electric signal is A
A binary signal having a black level signal corresponding to each black bar portion of the barcode 1 and a white level signal corresponding to each white bar portion of the barcode 1 is digitized by the D / D conversion unit 6. To be converted. After that, the bar width counter 7 counts the clock signal from the clock generator 8 so that the time width of the black level signal portion and the white level signal portion of the binarized signal from the A / D conversion unit 6 (actual The value corresponding to the width of each black bar and each white bar of barcode 1) is measured as the count value of the clock signal,
The count value is temporarily stored in the memory 9. And
In the CPU 10, the bar width count value stored in the memory 9 is subjected to a predetermined demodulation process to extract and demodulate the predetermined data of the bar code 1.

As described above with reference to FIG. 27, the bar code 1 has a plurality of black bars 1B and white bars 1W alternately arranged as shown in FIG. 28. The predetermined data is represented based on the width of the white bar 1W. These black bar 1B and white bar 1
Each W is set with a certain predetermined reference length as one module, and is a natural multiple of this one module (for example, 1 to 4).
Double; this multiple is called the number of modules).

Specifically, in the bar code 1 shown in FIG. 28, the number of modules is 2 on the left end side in the drawing.
Guide bar G consisting of one black bar 1B and one white bar 1W having one module between these black bars 1B and 1B
B is arranged, and on the right end side in the figure, a special consisting of three black bars 1B having one module and three white bars 1W having one module alternately arranged with the black bars 1B. Center bar SCB is arranged.

The guide bar GB and the special center bar SCB are for defining both ends of the bar code 1. For example, six pieces of numerical data are provided between the guide bar GB and the special center bar SCB. Character part to represent 1CHR (Character) to 6CHR
(Parts shown as time widths C1 to C6 in FIG. 28) are arranged.

Each character portion 1CHR to 6CHR is
It consists of two white bars 1W and two black bars 1B, and the total number of modules is 7. The black bar 1 on the left side in the figure
The number of modules from the left end of B to the left end of the right black bar 1B (corresponding to the time width T01) and the number of modules from the right end of the left black bar 1B to the right end of the right black bar 1B (time width T02 Each character part 1C
Predetermined numerical data is expressed for each of HR to 6CHR.

The relationship between the combination of the numbers of modules and the predetermined numerical data is known as shown in FIG. 29, for example, and is stored and held in advance as a table (matrix). 29, E indicates that EVEN, that is, the total module number of black bars 1B is an even number, and O indicates that ODD, that is, the total module number of black bars 1B is an odd number. For example, according to the UPC barcode configuration,
The character portion 1CHR in FIG. 28 is'ODD0.
(O0) ', character part 2CHR is'ODD1 (O
1) 'and the character portion 6CHR represent numerical data "ODD2 (O2)".

Therefore, in the CPU 10, based on the bar width count value stored in the memory 9, the time width (δ distance length) for each character portion 1CHR to 6CHR.
The data of the barcode 1 is extracted and demodulated by determining the number of modules of T01 and T02 and reading the numerical data corresponding to the combination of the two modules from a predetermined table stored in advance.

28, the reading of the bar code 1 in which the six character portions 1CHR to 6CHR are arranged between the guide bar GB and the special center bar SCB has been described, but as shown in FIG. Special center bar SCB on the right side of barcode 1 shown in
Is a center bar CB composed of two black bars 1B having one module and two white bars 1W having one module. Six character parts are arranged on the left and right with the center bar CB as the center, and Two black bars 1B with 1 module and 2 with 1 module at the end of
A type in which a left guide bar LGB composed of a white bar 1W of a book and a right guide bar RGB are generally arranged. In the following description of the present invention, FIG.
A case of reading the barcode 1 of the type 0 will be described. The reading of the barcode 1 of the type shown in FIG. 30 is also basically performed by the same procedure as that of the type shown in FIG.

Data extraction of barcode 1 shown in FIG.
In the demodulation processing, demodulation is usually performed in units of left and right blocks sandwiched between the left and right guard bars LGB, RGB of the barcode 1 and the center bar CB, and a general modulus 10 (modulus ten) is applied to the demodulation result. A check is performed, and if the check result is OK, it is determined that one reading of the barcode 1 (demodulation process) is completed.

At this time, the scanning mechanism 4 causes the bar code 1 to have about 1500 laser beams L per second.
When two of them are irradiated and even one of them crosses the barcode 1, one demodulation process is completed. However, in order to avoid erroneous reading of the barcode 1, even if a series of demodulations are completed, the demodulation is immediately performed. When the data is valid, the reading is not completed, the demodulation process is repeated for the same bar code 1, and the block unit data for which the modulus 10 check is OK match continuously for the specified number of times (match count check). Has completed reading. For example, a method in which the demodulated data of the barcode is captured twice and the reading is completed when the data of the previous time and the data of this time match is called a double-match check.

In the above-mentioned bar code reading method, as shown in FIG.
As shown in 1, the left and right guard bars LG of the barcode 1
When the left and right block units sandwiched by B, RGB and the center bar CB can be scanned by one scanning line A1, A2 respectively, that is, guard bars are provided at both ends of the demodulated data along each scanning line A1, A2. LGB or RGB
The demodulated data is valid only when and the center bar CB exist.

On the other hand, in recent years, as an optical system for irradiating the bar code 1 with the light beam, there is a system having a scanning direction of, for example, 16 directions. The angle formed by the scanning direction of the bar code 1 and the bar code 1 is large, and as shown in FIG. 31, the left and right blocks sandwiched between the left and right guard bars LGB, RGB of the bar code 1 and the center bar CB by one scanning line. It may not be possible to scan the entire unit.

For example, as shown in FIG. 32, when one bar code 1 is divided into three parts and scanned by three scanning lines A1 to A3, demodulated data is obtained by the above bar code reading method. Although it was not possible, in recent years, even when division scanning as shown in FIG. 32 is performed,
The scanning lines A1 to A3 are demodulated as much as possible, and a plurality of (three in this case) obtained demodulated data are combined in a possible pattern to demodulate the data of one bar code. There is.

However, at this time, each scanning line A1 to A
The demodulated data obtained for every 3 includes at least one of the guard bar or the center bar, and the demodulated data obtained for each of the scanning lines A1 to A3,
When the character at the end overlaps with the character at the end of the other adjacent demodulated data (character duplication check), the demodulated data is validated. FIG.
The shaded portion indicates the character overlapping portion.

[0025]

By the way, in recent years, as represented by POS systems used in the distribution industry and the like, the use of bar codes has become popular, but the bar code printing quality is low. The number of barcodes having such a low print quality is highly likely to be erroneously read, and the probability of erroneously reading paper noise and characters as barcode data is considerably high.

Therefore, it is desired to be able to read a barcode with high accuracy without misreading even a barcode having a low print quality. In addition, erroneous reading of the bar code is also caused by bending or wrinkling of the bar code, scratches of glass on the reading window surface of the bar code reading device, and the like.
Further, after the light beam passes through the guard bar, the center bar, and the regular character, paper surface noise, characters, etc. are erroneously read as a bar code character and demodulated. In such a case, if the above-mentioned character duplication check is OK. The demodulation result becomes invalid.

Therefore, in order to avoid erroneous reading, as described above, conventionally, when the same data is continuously demodulated a predetermined number of times, the demodulation result is validated. In such a check of the number of coincidences, the reference number of times is always constant, and therefore there is a possibility of misreading depending on the reading state of the barcode. It may be possible to set the reference number large from the beginning, but in that case, even if reading can be performed with almost no mistake in one scanning and demodulation process, the same data is demodulated by the reference number. Since the demodulation result is not validated until
There is a problem that it takes time to read the barcode.

The present invention was devised in view of the above problems, and when one bar code is divided into a plurality of parts for scanning and demodulation, the number of coincidences is checked according to the bar code reading state. It is an object of the present invention to provide a bar code reading method and a bar code reading device, which are capable of performing reading and improving the reading rate and reducing the erroneous reading rate in actual operation without lowering the reading efficiency.

[0029]

FIG. 1 is a block diagram showing the principle of the present invention. In FIG. 1, 1 is a bar code and 2A is a beam for irradiating the bar code 1 with beam light and reflecting from the bar code 1. Optical system for receiving the reflected light of the beam light, 3A is a light source for emitting the beam light, 4A is a light source 3
Scanning means for irradiating the bar code 1 with a plurality of light beams from A and scanning the bar code 1 with each light beam,
Reference numeral 5A denotes a photoelectric conversion unit that receives the reflected light of each beam of light from the barcode 1 and converts it into an electric signal corresponding to the amount of light, and the optical system 2A includes the above-described light source 3A, scanning unit 4A, and photoelectric conversion unit 5A. It consists of

Reference numeral 11 is a demodulation means, 12 is a combination means, 13 is a coincidence frequency determination means, 14 is a reading state information acquisition means, and 15 is a reference frequency change means. Here, the demodulation means 11 is based on the electric signal from the photoelectric conversion means 5A, and the barcode 1 partially scanned by each light beam.
The demodulating means 12 combines the demodulated data of a plurality of portions of the barcode 1 demodulated by the demodulating means 11 to demodulate the data of the barcode 1. Is.

The coincidence number determination means 13 detects the number of times the same data is continuously demodulated from the bar code 1 by the demodulation means 11 and the combination means 12, compares the number of times with a predetermined reference number, and When the number of times reaches a predetermined reference number, the data demodulated from the barcode 1 is validated and the reading of the barcode 1 is completed. The reading state information acquiring unit 14 acquires the reading state information of the barcode 1, and the reference number changing unit 1
Reference numeral 5 denotes the coincidence number determination means 1 according to the read state information of the barcode 1 acquired by the read state information acquisition means 14.
The reference number in 3 is set and changed.

As the reading state information acquiring means 14, various means described in the following items (1) to (4) are used. The number of characters that have been demodulated in duplicate in the demodulated data for multiple parts of barcode 1 is
Character number detecting means for detecting the reading state information of the character.

Character number detecting means for detecting the number of characters having different demodulation results in the duplicated portions of the demodulated data of a plurality of portions of the barcode 1 as the reading state information of the barcode 1. Overlapping position detecting means for detecting the position of the overlapping portion in the demodulated data of a plurality of portions of the barcode 1 as the reading state information of the barcode 1.

Combination pattern detecting means for detecting the combination pattern of the demodulated data combining means 12 for a plurality of portions of the barcode 1 as the reading status information of the barcode 1. Distortion amount measuring means for calculating / measuring the reading strain amount of a portion where a plurality of portions of the barcode 1 overlap each other as the reading state information of the barcode 1. Further, as the distortion amount measuring means, (a) a device for calculating / measuring the distortion amount of the character length of a portion where a plurality of portions of the barcode 1 overlap each other,
(B) Calculating and measuring the amount of distortion of the δ distance length obtained for each character in order to specify the character data of a portion where a plurality of portions of the barcode 1 mutually overlap, and (c) of the barcode 1 It is also possible to use one that calculates and measures the amount of distortion of the bar itself that forms the character of the portion where a plurality of portions overlap each other.

Bit shift data detecting means for outputting information as to whether or not the data in a plurality of portions of the bar code 1 are different data when bit shift is performed, as the reading state information of the bar code 1. Wave error detection means for outputting the presence / absence of a wave error in a plurality of portions of the barcode 1 as the reading status information of the barcode 1.

The guard bar / center which outputs, as the reading state information of the bar code 1, information indicating whether or not there is a bar code of the bar code 1 that has detected both the guard bar and the center bar among a plurality of parts. Bar detection means. It should be noted that a plurality of the above-described respective means may be used in combination.

[0037]

With the above-described structure, in the present invention, as shown in FIG. 1, a plurality of light beams emitted from the light source 3A are respectively radiated toward the bar code 1 by the scanning means 4A at a constant speed. It is moved / scanned, scattered / reflected by a plurality of portions of the barcode 1, and enters the photoelectric conversion means 5A as reflected light.

Each reflected light from a plurality of portions of the bar code 1 is converted into an electric signal according to the amount of light by the photoelectric converting means 5A, and based on the electric signal, the demodulating means 11 detects a plurality of portions of the bar code. After the data is demodulated as much as possible, these demodulated data are combined by the combining means 12 to demodulate the data of the barcode 1.

When the data of the bar code 1 is demodulated, the coincidence number determining means 13 causes the bar code 1
When the number of times the same data is continuously demodulated is detected from the above, and the number reaches the predetermined reference number, the data demodulated from the barcode 1 is validated and the reading of the barcode 1 is completed. At this time, in the present invention, the reading state information acquiring unit 14 acquires the reading state information of the barcode 1, and the reference number changing unit 15 responds to the reading state information of the barcode 1 from the reading state information acquiring unit 14. The reference number in the coincidence number determination means 13 is changed.

That is, in the prior art, the number of coincidences is always determined with a fixed reference number. However, according to the present invention, the reference number is determined according to the reading status information of the bar code 1 when there is a high possibility of misreading. Is set to be large, and the reference number can be set to be small when the possibility of misreading is low. The reading status information of the bar code acquired by the reading status information acquiring unit 14 includes, as described above, the number of characters that are demodulated in duplicate in the demodulation data of a plurality of parts of the bar code 1, and the bar code. 1. The number of characters with different demodulation results in the demodulated data of the plurality of 1's, the position of the overlapping portion in the demodulated data of the plurality of 1's of barcode 1, the demodulated data of the plurality of 1's of barcode 1 Of the combination pattern of the combination means 12 and the reading distortion amount of a portion where a plurality of portions of the barcode 1 overlap each other (distortion amount of character length, distortion of δ distance length obtained for each character to identify character data). amount,
(The amount of distortion of the bar itself forming the character), information on whether or not the data in a plurality of portions of the barcode 1 can be different data when bit shifting is performed,
Information on whether or not a wave error has occurred in a plurality of portions of the barcode 1 and whether or not there is a guard bar and a center bar of the barcode 1 detected among the plurality of portions of the barcode 1 are used. .

[0041]

Embodiments of the present invention will be described below with reference to the drawings. (A) Description of First Embodiment FIG. 2 is a block diagram showing a hardware configuration of a bar code reader as a first embodiment of the present invention. As shown in FIG. 2, the method and apparatus of the present embodiment. Is also for extracting, demodulating and reading the data of the barcode 1 printed on the surface of an article or the like.

Further, the bar code 1 is formed by alternately arranging a plurality of black bars 1B and white bars 1W as described above with reference to FIG. 29, and each black bar 1B and each white bar 1W.
The predetermined data is represented based on the width of. Then, as shown in FIG. 6, the left guide bar LGB and the right guide bar RGB that define the left and right ends of the barcode 1.
And the center bar CB that defines the central part of the barcode 1.
There is a left guide bar LGB and a center bar CB.
Character portions A to F and G to L representing six numerical value data are arranged between and, and between the light guide bar RGB and the center bar CB, respectively.

Each of the character parts A to L is, for example, as shown in FIG.
Similar to the one described in 9, the total number of modules is composed of two white bars 1W and two black bars 1B, and the left end of the left black bar 1B to the left end of the right black bar 1B. To the right black bar 1B from the right end of the left black bar 1B and the number of modules calculated from the time width (δ distance length) T01
By combining with the number of modules calculated from the time width (δ distance length) T02 to the right end of each character part A
Predetermined numerical data is expressed for each L. The relationship between the combination of the number of modules and the predetermined numerical data is known, and is stored in advance as a table (matrix).
Is held.

Further, similarly to the one shown in FIG. 27, reference numeral 2 is an optical system composed of a laser emitting portion (light source) 3, a scanning mechanism (scanning means) 4 and a photoelectric conversion portion (photoelectric conversion means) 5, which is a laser. The light emitting unit 3 is a laser beam (beam light) L1.
The scanning mechanism 4 has a semiconductor laser that emits light.
Is composed of, for example, a polygon mirror rotationally driven by a motor, and the photoelectric conversion section 5 is composed of, for example, a photoelectric conversion element such as a photodiode.

However, in the present embodiment, the scanning mechanism 4 irradiates the barcode 1 with the laser beam L1 from the laser emitting section 3 as a plurality of laser beams L2, and scans the barcode 1 with each laser beam L2. On the other hand, by reflecting the reflected light R1 of the laser beam L2 from the bar code 1 while having the function of causing the reflected light R1 moving along with the scanning of each laser beam L2 to be incident on the photoelectric conversion unit 5 as reflected light R2. It also has a function.

The photoelectric conversion unit 5 receives the reflected light R2 received from the bar code 1 of each laser beam L2 through the scanning mechanism 4 and converts it into an electric signal corresponding to the amount of light. . Further, in the subsequent stage of the photoelectric conversion section 5, an A / D conversion section 6, a bar width counter 7, a clock generator 8, a memory 9 and a CPU 1 having the same configuration as the conventional one are provided.
0 is provided.

As in the conventional case, the A / D conversion unit 6 digitizes the electric signal from the photoelectric conversion unit 5,
Binarization of a black level signal (Low level signal) corresponding to each black bar 1B forming the barcode 1 and a white level signal (High level signal) corresponding to the white bar 1W forming the barcode 1 It is converted into a signal. The bar width counter 7 counts the clock signal from the clock generator 8, and the time width of the black level signal portion and the white level signal portion of the binarized signal from the 1 / D conversion unit 6,
That is, a value corresponding to the width of each black bar 1B and each white bar 1W of the actual barcode 1 is output as the count value of the clock signal. Further, the memory 9 stores the bar width count value from the bar width counter 7.

The CPU 10 of this embodiment also uses the bar width count value (the value corresponding to the width of each black bar 1B and each white bar 1W) stored in the memory 9 as the predetermined data of the bar code 1. The CPU 10 of this embodiment has a functional configuration as will be described later with reference to FIG. As shown in FIG. 2, a ROM 21, a RAM 22, an interface section 23, and a control section circuit 24 are connected to the CPU 10.

Here, the ROM 21 stores various programs necessary for executing various processes, a table for holding the relationship between the combination of the number of modules described above and predetermined numerical data, and the RAM 22. , CPU1
It is used as a work area during the operation of 0, and functions as a demodulation data storage unit 22A described later in FIG. 3, for example.

Further, the interface section 23 exchanges data (bar code reading result, etc.) with an external device (not shown).
And the control circuit 24
Is for controlling the operation of the barcode reading device in response to various instructions from the CPU 10, and includes a motor driving unit 25 for driving and controlling the motor of the scanning mechanism 4 and a semiconductor laser of the laser emitting unit 3. It controls the operations of the laser drive unit 26 for controlling light emission, the light emitting diode (LED) 27, the speaker 28, and the like. The light emitting diode 27 and the speaker 28 are, for example, the barcode 1
When the reading of is completed, the operator is notified by light or sound.

Next, the functional configuration of the bar code reading apparatus as the first embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 3, the CPU 10 of this embodiment includes a bar code data detecting section 31, a bar code demodulating section 32, a bar code synthesizing section 33, a data comparing section 34, and a modulus 10.
The RAM 22 of the present embodiment has a function as a demodulation data storage unit 22A, in addition to the functions of the check unit 35, the match count checking unit 36, the reference count changing unit 37, and the barcode reading completion notifying unit 38. .

Here, the bar code data detecting section 31 is
The center bar CB and the guard bars LGB, RGB are detected from the data (stored in the memory 9) of a plurality of portions of the barcode 1 to be read, and the adjacent characters are checked and the number of effective characters is extracted. It is a thing. As described above, in this embodiment,
One bar code 1 is divided into a plurality of parts to be scanned, and the center bar CB is included in the data of each part.
And at least one of the two guard bars LGB, RGB is always included, the barcode 1
It is judged that the reading of is valid. Such a determination is also made by the barcode data detection unit 31. The barcode data detection unit 31
Is the data of a part of the barcode 1 which is divided and scanned,
Center bar CB and two guard bars LGB, RG
If neither B is included, a reread instruction is output.

The bar code demodulation section (demodulation means) 32 uses the bar width count value (that is, the electric signal from the photoelectric conversion section 5) stored in the memory 9 for the valid character extracted by the bar code data detection section 31. Based on, it demodulates to data such as letters and numbers. That is, in this embodiment, the center bar CB and the two guard bars LG
Each data including at least one of B and RGB (1
Bar code demodulator 32.
Is demodulated as much as possible by the
The data is stored in the demodulation data storage unit 22A of 22.

The bar code synthesizing unit (combining unit) 33 combines a plurality of demodulated data stored in the demodulated data storage unit 22A, and the bar code 1 which is currently the reading target.
This is for synthesizing and demodulating the data (a series of barcode data) owned by. Further, the barcode synthesizing unit 33 has a function of determining whether or not mutually adjacent portions of a plurality of demodulated data are positionally overlapped (position duplication check function) when performing the combination processing as described above. If there is a position overlapping portion, the combined series of barcode data is validated, and if there is no position overlapping portion, a reread instruction is output.

The data comparison unit 34 determines whether the character at the end of the plurality of demodulated data obtained for each scanning line matches or overlaps the character at the end of the other demodulated data adjacent thereto. , Which has a function to judge by data comparison (character duplication check function), and validates a plurality of demodulated data obtained for barcode 1 to be read when at least one character at the end matches (overlaps) It has become. The data comparison unit 3
No. 4 outputs a rereading instruction when there is no overlapping character.

Further, the data comparison section 34 described above is
In the embodiment, when performing the character duplication check as described above, the number of characters that have been demodulated in duplicate in the demodulated data of a plurality of portions of the barcode 1 (the number of duplicate characters) is determined by the reading state of the barcode 1. It functions as a reading state information acquisition unit (character number detection unit) that detects and acquires information.

The modulus 10 check unit 35, when effective data as the demodulation data of the barcode 1 to be read is synthesized by the barcode synthesis unit 33, a general modulus for the synthesis result (demodulation result). 10 (modu
If the check result is OK, it is determined that one-time reading (demodulation processing) of the barcode 1 to be read has been completed. The modulus 10 check unit 35 determines that the check result is N
If it is G, a reread instruction is output.

Matching frequency check unit (matching frequency determining means)
The bar code data detector 36, the bar code demodulator 32, the bar code synthesizer 33, the data comparator 34, and the modulus 10 checker 35 function to read one bar code 1 (demodulation process). When completed, the number of times the same data is continuously demodulated from the barcode 1 to be read is detected, and the number of times is compared with a predetermined reference number set by a reference number changing unit 37 described later, When the number of times reaches a predetermined reference number, the data demodulated from the barcode 1 is validated and the reading of the barcode 1 is completed. The coincidence number check unit 36 outputs a re-reading instruction when the current reading result is different from the previous reading result or when the number of times is less than a predetermined reference number.

Reference number changing unit (reference number changing means) 37
Is the predetermined reference number in the matching number check unit 36 according to the number of overlapping characters (reading state information of the bar code 1) obtained by the function of the data comparing unit 34 as the reading state information acquiring unit. The setting is changed. In addition, the reference number changing unit 3 in the first embodiment.
The detailed setting change operation of No. 7 will be described later with reference to FIG.

The bar code reading completion notifying section 38 is shown in FIG. 2 when the coincidence number checking section 36 determines that the continuous demodulation number of the same data has reached a predetermined reference number and completes the reading of the bar code 1. Interface section 23
Also, the control circuit 24 is instructed to notify the reading completion. Interface unit 23 that received this instruction
In addition to transmitting the fact that the reading is completed to the host device, the control unit circuit 24 which has received the instruction notifies the operator etc. that the reading is completed by driving the LED 27 to light up and outputting a sound from the speaker 28. It is supposed to do.

Next, the flow of the overall operation of the first embodiment of the present invention configured as described above will be described with reference to the flow chart (steps S1 to S14) shown in FIG. First, the CPU 10 gives a reading instruction to the control unit circuit 24, and the motor driving unit 25 and the laser driving unit 26 respectively operate the scanning mechanism 4 and the laser emitting unit 3 to perform the divided reading process of the barcode 1 ( Step S1).

That is, in the present embodiment, the laser beam L1 emitted from the laser emitting section 3 is irradiated by the scanning mechanism 4 as a plurality of laser beams L2 toward the black bar 1B and the white bar 1W of the bar code 1. Then, the bar code 1 is moved and scanned at a constant speed in a direction intersecting the black bar 1B and the white bar 1W of the bar code 1. The plurality of laser beams L2 emitted from the scanning mechanism 4 are scattered / reflected at the bar code 1 and re-enter the scanning mechanism 4 as a plurality of reflected lights R1. The reflected light R1 changes its reflection angle with the scanning movement of the laser beam L2 and moves, but by being reflected by the polygon mirror constituting the scanning mechanism 4, it is arranged at a predetermined position as the reflected light R2. The light enters the photoelectric conversion element of the photoelectric conversion unit 5.

The photoelectric conversion unit 5 converts each reflected light R2 into an electric signal corresponding to the amount of light, and the electric signal is
Bar code 1 digitized by A / D converter 6
Is converted into a binarized signal having a black level signal corresponding to each black bar 1B portion and a white level signal corresponding to each white bar 1W portion of the barcode 1. After that, the bar width counter 7 counts the clock signal from the clock generator 8 so that the time width of the black level signal portion and the white level signal portion of the binarized signal from the A / D conversion unit 6 (actual A value corresponding to the width of each black bar 1B and each white bar 1W of the bar code 1) is measured as a count value of the clock signal, and the count value is temporarily stored in the memory 9.

As a result, in this embodiment, a plurality of divided read data obtained by reading a part of the bar code 1 is obtained from one bar code 1. Then, the barcode data detection unit 31 detects whether or not each divided read data stored in the memory 9 includes at least one of the center bar CB and the two guard bars LGB, RGB (step S2). , S3), the center bar CB and the two guard bars LGB and RGB do not include any divided read data,
Returning to step S1, the barcode 1 is read again.

When each divided read data includes at least one of the center bar CB and the two guard bars LGB, RGB, the bar code demodulation section 32.
Thus, demodulation processing is performed on each divided read data (step S4). The bar code demodulation unit 32 demodulates the effective characters of each divided read data extracted by the bar code data detection unit 31 into data such as letters and numbers as much as possible based on the bar width count value stored in the memory 9. To be done. More specifically, with reference to the positions of the center bar CB and the guard bars LGB, RGB included in each data, as described with reference to FIG.
~ L (see FIG. 6), the time width (δ distance length) T
The number of modules of 01 and T02 is determined, and the numerical data corresponding to the combination of the two modules is stored in the ROM 21.
The data of the barcode 1 is extracted and demodulated by reading from a predetermined table stored in advance in the.

The plurality of demodulated data demodulated for each divided read data as described above is temporarily stored in the demodulated data storage section 22A on the RAM 22 (step S5). Then, the barcode combining unit 33 combines the plurality of demodulated data stored in the demodulated data storage unit 22A,
A series of data of the bar code 1, which is the current reading target, is combined and demodulated (step S6).

When a series of barcode data cannot be synthesized by the barcode synthesizing section 33 (for example, when it is judged by the position duplication checking function that there is no position duplication portion; when NO is determined in step S7). Then, the process returns to step S1 and the barcode 1 is read again. on the other hand,
When a series of barcode data can be synthesized by the barcode synthesizing unit 33 and a combination of a plurality of demodulated data is completed (YES in step S7), the data comparing unit 34 causes each scanning line to be scanned. With respect to the plurality of demodulated data obtained in (1), the character at the end (duplicate character part) of each demodulated data is compared with the character at the end (duplicate character part) of other adjacent demodulated data (step S8). , It is determined whether these characters match or overlap (step S9).

If it is determined that there are no overlapping characters (NO in step S9), step S9 is performed.
When it is determined that there is a duplicate character by returning to 1 and reading the barcode 1 again (YES in step S9).
In the case of S determination), the modulus 10 check unit 35 performs a modulus 10 check process on a series of data (synthesis result) obtained for the barcode 1 to be read (step S10).

If the check result is NG (NO determination in step S11), the process returns to step S1 to reread the barcode 1, and if the check result is OK (YES determination in step S11), the bar Code 1 of 1
It is determined that the reading (demodulation process) for the number of times has been completed, and the matching number checking unit 36 performs the matching number checking process (step S12).

In the coincidence count checking unit 36, every time one reading (demodulation process) of the barcode 1 is completed, the same data is continuously demodulated from the barcode 1 to be read by that point. The number of times (the number of consecutive demodulations) is detected,
The number of continuous demodulations is compared with a predetermined reference number of times whose setting is changed as described later. As a result of the comparison, when the number of times of continuous demodulation is less than the predetermined reference number, or when the current reading result is different from the previous reading result (step S1
If NO in 3), the process returns to step S1 to reread the barcode 1.

On the other hand, when the number of continuous demodulations reaches a predetermined reference number (YES in step S13)
, The data demodulated from the barcode 1 is validated, and the reading of the barcode 1 is completed. At this time, the barcode reading completion notification unit 38 causes the interface unit 2 to
3 and the control unit circuit 24 are instructed to notify the completion of reading, and the upper device, the operator, etc. are notified that the reading of the barcode 1 to be read is completed (step S1).
4).

By the way, when one bar code 1 is divided into a plurality of parts and read as described above, the demodulated data obtained for each scanning line are different from each other in the demodulated data. The larger the number of matching characters (the number of overlapping characters) in the overlapping portion, the lower the possibility of misreading the barcode 1. That is, the larger the number of overlapping characters, the higher the reliability of the divided reading result. Therefore, even if the predetermined reference number in the matching number checking unit 36 is set small, there is almost no possibility of misreading.

For example, as shown in FIG. 6, consider a case where one bar code 1 is read by being divided into two parts by two scanning lines A1 and A2. Here, in the first pattern, the characters of the barcode 1 demodulated by the scanning line A1 are A to F, G, H, I, and J.
Then, it is assumed that the characters of the barcode 1 demodulated by the scan line A2 are J, K and L. In the second pattern, the barcode 1 demodulated by the scan line A1
Characters A to F, G, H, I, and J, and the character of the barcode 1 demodulated by the scanning line A2 is I,
J, K, L.

At this time, in the first pattern, the only overlapping character is J at the end, and the number of overlapping characters is one. In this case, there is a high possibility that both the character J at the end of the demodulated character by the scan line A1 and the character J at the end of the demodulated character by the scan line A2 are misread, and therefore these characters match. -Reliability of demodulated data is low, even if duplicated.

In the second pattern, the demodulated characters are I and J, and the number of duplicate characters is 2. In this case, there is a high possibility that the character J at the end of the demodulated character by the scan line A1 and the character I at the end of the demodulated character by the scan line A2 are misread.
However, the second character I from the end of the demodulated character by the scan line A1 and the second character J from the end of the demodulated character by the scan line A2 are highly reliable.

That is, in this second pattern, the character J at the end of the demodulated character by the scanning line A1 is used.
And the character J, which is the second character from the end of the demodulated character by the scan line A2, match, and the character I at the end of the demodulated character by the scan line A2.
And the second character I from the end of the demodulated character by the scan line A1 coincides with each other, and there is no possibility that the ones having a high possibility of misreading will overlap with each other. And the reliability of the demodulated data is much higher.

Therefore, in the first embodiment, the smaller the number of duplicate characters, the higher the possibility of misreading. Therefore, in order to improve the reliability, the reference number changing unit 37 causes the matching number checking unit 3
The reference number in 6 is largely changed. At this time, the number of duplicate characters is detected by the function of the reading state information acquisition unit (character number detection unit) of the data comparison unit 34 when the above-described character duplication check is performed.

The operation of the reference number setting changing process by the reference number changing unit 37 will be described according to the flow chart (steps S21 to S27) shown in FIG. 5. If the number of duplicate characters detected by the data comparing unit 34 is one. If YES in step S21), the reference number in the coincidence number checking unit 36 is set to 3, that is, the number of times the data of the barcode 1 to be read is taken in is changed to 3 (step S22).

If the number of duplicate characters detected by the data comparison unit 34 is 2 (YE in step S23)
In the case of S determination), the reference number in the coincidence number checking unit 36 is changed to 2, that is, the number of times the data of the barcode 1 to be read is taken in is changed to 2 (step S24). Furthermore, the number of duplicate characters detected by the data comparison unit 34 is 3
If the above is satisfied (YES in step S25),
The reference number in the coincidence number checking unit 36 is changed to 1, that is, the number of times the data of the barcode 1 to be read is taken in is changed to 1 (step S26). Here, when the reference number of times is set to 1, the reliability of the demodulated data is extremely high and the check by the match number check unit 36 is unnecessary. Therefore, the demodulated data is validated as it is without performing the match number check. The reading of the barcode 1 is completed.

When NO is determined in step S25 (when it is determined that the number of overlapping characters is not 3 or more)
, It is determined that the number of overlapping characters is 0 or some error has occurred, and an instruction to reread the barcode 1 is issued (step S27). As described above, according to the first embodiment of the present invention, according to the number of duplicate characters which is the reading status information of the barcode 1, when the number of duplicate characters is small and the possibility of misreading is high, the reference number of times is set large. If the number of duplicate characters is large and the possibility of misreading is low, the reference number of times is set small.

Therefore, when one bar code 1 is divided into a plurality of parts for scanning and demodulation, it is possible to check the number of coincidences according to the reading state (the number of overlapping characters) of the bar code 1 and the reading efficiency. The reading rate in actual operation is significantly improved and the misreading rate is greatly reduced without causing a decrease in In particular, in the form of removing characters that were accidentally demodulated due to paper noise or characters,
Multiple demodulated data can be combined and the misreading rate is greatly reduced. Further, when there is no paper surface noise or characters in the background of the barcode 1, the reading accuracy can be greatly improved.

In the first embodiment described above, as shown in FIG. 5, the reference number changing unit 37 sets the reference number to 3 when the number of overlapping characters is 1, and sets the number of overlapping characters to 2 Although the reference number is set to 2 in this case and the reference number is set to 1 when the number of overlapping characters is 3 or more, the present invention is not limited to this value.

Further, in the above-mentioned first embodiment, as shown in FIG. 6, one bar code 1 is used for two scanning lines A.
Although the case of reading in the form of being divided into two by 1 and A2 has been described, the present invention is not limited to this and is similarly applied to the case where one barcode 1 is divided into three or more and read. As a result, the same effect as that of the first embodiment can be obtained.

(B) Description of Second Embodiment The hardware configuration of the bar code reader as the second embodiment of the present invention is exactly the same as that of the first embodiment shown in FIG. The functional configuration of the bar code reading apparatus as the second embodiment of the present invention is almost the same as that of the first embodiment as shown in FIG. 7, but in the second embodiment, data comparison is performed. The functions of the unit 34A and the reference number changing unit 37A are slightly different from the functions of the data comparing unit 34 and the reference number changing unit 37 of the first embodiment shown in FIG. In FIG. 7, the same reference numerals as those used above denote the same parts, and a description thereof will be omitted.

That is, the data comparison section 34A of the second embodiment.
When performing the same character duplication check as in the data comparison unit 34 of the first embodiment, the number of characters with different demodulation results (the number of unmatched characters) in the duplicated parts of the demodulated data of a plurality of barcodes 1 is calculated. , And functions as a reading state information acquiring unit (character number detecting unit) that detects and acquires the reading state information of the barcode 1.

Further, the reference number changing unit (reference number changing means) 37A of the second embodiment is the data comparing unit 34A described above.
The number of non-matching characters obtained by the function as the reading state information acquiring unit (reading state information of barcode 1)
In accordance with the above, the predetermined reference number of times in the matching number check unit 36 is set and changed. The detailed setting changing operation of the reference number changing unit 37A in the second embodiment will be described later with reference to FIG.

The overall operation flow of the second embodiment of the present invention constructed as described above is exactly the same as that of the first embodiment described according to the flow chart shown in FIG. 4, and therefore the description thereof is omitted. To do. By the way, when one bar code 1 is divided into a plurality of parts and read as described above,
In multiple demodulated data obtained for each scan line,
The reliability of the demodulated data of the barcode 1 becomes lower as the number of characters having different demodulation results (the number of non-matching characters) is larger in a portion where each demodulated data and another adjacent demodulated data overlap. Therefore, the larger the number of mismatched characters,
It is desired to increase the predetermined reference number in the coincidence number checking unit 36 to improve the reliability of the divided reading result.

For example, as in the case of the first embodiment shown in FIG. 6, one bar code 1 is replaced with two scanning lines A1, A.
Consider the case where the data is divided into two parts and read by step 2. Here, in the first pattern, the scan line A
The characters of barcode 1 demodulated by 1 are AF,
It is assumed that the characters of the barcode 1 demodulated by the scan line A2 in G, H, I, and J'are I, J, K, and L. In the second pattern, the characters of the barcode 1 demodulated by the scanning line A1 are A to F, G, H, and
It is assumed that the characters of the barcode 1 demodulated by the scan line A2 in I are I, J, K, and L.

At this time, in the first pattern, the overlapping portion exists for two characters (I and I, J and J '), but the actual overlapping character is only one I, and the scanning line A
The character J ′ at the end of the demodulated character by 1;
The character J, which is the second character from the end of the demodulated character by the scanning line A2, does not match. That is, the number of unmatched characters is 1.

The occurrence of such a mismatch means that
It is conceivable that erroneous reading due to characters or paper surface noise other than the barcode 1 has occurred. Therefore, although the character I overlaps with the two demodulated data, the reliability of the character I at the end of the demodulated character due to the scan line A2 becomes low, and the read result is valid only by overlapping the character I. , The possibility of misreading is increased.

In the second pattern, the overlapping portion is for one character, and two characters I are included in this overlapping portion.
Are matched. That is, the number of unmatched characters is 0. In this case, the possibility that erroneous reading due to characters or paper surface noise other than the barcode 1 may be much lower than that in the case of the first pattern. Therefore, in the second embodiment, the larger the number of non-matching characters, the higher the possibility of misreading. Therefore, in order to improve the reliability, the reference number changing unit 37A largely changes the reference number in the matching number checking unit 36. At this time, the number of unmatched characters is
By the function of the reading state information acquisition means (character number detection means) of the data comparison unit 34A, it is detected when the above-mentioned character duplication check is performed.

The operation of the reference number setting changing process by the reference number changing unit 37A will be described with reference to the flowchart (steps S31 to S37) shown in FIG. 8. If the number of mismatched characters detected by the data comparing unit 34A is zero. In the case of YES determination in step S31, the reference number in the coincidence number checking unit 36 is set to 1, that is, the number of times the data of the barcode 1 to be read is taken in is changed to 1 (step S32). Here, if the reference number of times is set to 1, as described above in the first embodiment, the reliability of the demodulated data is high and the matching number checking unit 36 does not need to check it. Instead, the demodulated data is validated as it is, and the reading of the barcode 1 is completed.

If the number of non-matching characters detected by the data comparing section 34A is 1 (YES in step S33), the reference number in the matching number checking section 36 is 2, that is, the barcode 1 to be read. The number of times the data is captured is changed to 2 (step S34). Further, if the number of non-matching characters detected by the data comparing unit 34A is 2 or more (YES in step S35), the reference number of times in the matching number checking unit 36 is 3,
That is, the number of data acquisitions of the barcode 1 to be read is set to 3
The setting is changed to (step S36).

If NO is determined in step S35 (if it is determined that the number of non-matching characters is not 2 or more), it is determined that some error has occurred, and the re-reading of the bar code 1 is instructed ( Step S37). Thus, according to the second embodiment of the present invention, the barcode 1
According to the number of non-matching characters, which is the reading status information, the reference number is set to a large number when the number of non-matching characters is high and the possibility of misreading is high. The number of times is set small.

Therefore, when one bar code 1 is divided into a plurality of parts for scanning and demodulation, the number of coincidences can be checked according to the reading state of the bar code 1 (the number of non-coincident characters). The same effect as the embodiment can be obtained. In the second embodiment described above, as shown in FIG. 8, the reference number changing unit 37A sets the reference number to 1 when the number of mismatched characters is 0, and sets the reference number when the number of mismatched characters is 1. The example in which the number of times is set to 2 and the reference number of times is set to 3 when the number of unmatched characters is 2 or more has been described, but the present invention is not limited to this number.

Further, in the above-described second embodiment, as shown in FIG. 6, one bar code 1 is used for two scanning lines A.
Although the case of reading in the form of being divided into two by 1 and A2 has been described, the present invention is not limited to this and is similarly applied to the case where one barcode 1 is divided into three or more and read. As a result, the same effect as that of the second embodiment can be obtained.

(C) Description of Third Embodiment The hardware configuration of the bar code reader as the third embodiment of the present invention is exactly the same as that of the first embodiment shown in FIG. The functional configuration of the bar code reader as the third embodiment of the present invention is almost the same as that of the first embodiment as shown in FIG. 9, but in this third embodiment, data comparison is performed. The functions of the unit 34B and the reference number changing unit 37B are slightly different from the functions of the data comparing unit 34 and the reference number changing unit 37 of the first embodiment shown in FIG. In FIG. 9, the same reference numerals as those used above indicate the same parts, and a description thereof will be omitted.

That is, the data comparison unit 34B of the third embodiment.
When performing the same character duplication check as in the data comparison unit 34 of the first embodiment, the position of the overlapping portion (overlapping position) in the demodulated data of a plurality of portions of the barcode 1 is read by the barcode 1 reading state. It functions as a reading state information acquisition unit (overlapping position detection unit) that detects and acquires information.

The reference number changing unit (reference number changing means) 37B of the third embodiment is the same as the data comparing unit 34B described above.
According to the overlapping position (reading state information of the barcode 1) obtained by the function of the reading state information acquiring unit of
The predetermined reference number of times in the coincidence number check unit 36 is set and changed. The detailed setting changing operation of the reference number changing unit 37B in the third embodiment is as follows.
This will be described later with reference to FIG.

The overall operation flow of the third embodiment of the present invention constructed as described above is exactly the same as that of the first embodiment described according to the flow chart shown in FIG. 4, and therefore the description thereof is omitted. To do. By the way, when one bar code 1 is divided into a plurality of parts and read as described above,
The former data is more reliable between the data demodulated by the scanning line passing through both the guide bar and the center bar and the data demodulated by the scanning line passing through only the guide bar (or the center bar). Needless to say. In the example shown in FIG. 6, the scan line A1 includes the left guide bar LGB and the center bar C.
The scanning line A2 passes through both B and the light guide bar RGB only. In such a case, the demodulation data by the scanning line A1 is more reliable than the demodulation data by the scanning line A2.

If a column display is written near the barcode 1 on the surface of a newspaper or the like on which the barcode 1 is printed, there is a high possibility that the column will be misread as a guide bar. . That is, if the number of duplicate characters described above in the first embodiment is the same, the reliability of the demodulation data including only the guide bar becomes higher as the number of characters in the demodulation data becomes larger.

Therefore, the smaller the number of characters in the demodulated data including only the guide bar, that is, the closer the position of the overlapping character (overlapping position) is to the guide bar side, the more the predetermined reference number in the coincidence number checking section 36 becomes. It is desired to set a large value to improve the reliability of the divided reading result. For example, as in the case of the first embodiment shown in FIG.
Consider a case where one bar code 1 is read by being divided into two parts by two scanning lines A1 and A2.

Here, in the first pattern, the scan line A
Left guide bar LGB and center bar C by 1
The character of barcode 1 demodulated including B is from A to
In F, G, H, I and J, the characters of the barcode 1 demodulated including the light guide bar RGB by the scanning line A2 are J, K and L. In the second pattern, the left guide bar LGB is scanned by the scan line A1.
And bar code 1 demodulated including center bar CB
Characters A to F, G, and H, and the characters of the barcode 1 demodulated including the light guide bar RGB by the scanning line A2 are H, I, J, K, and L.

At this time, in the first pattern, one overlapping character is J, in the second pattern, one overlapping character is H, and the number of overlapping characters is the same in both the first pattern and the second pattern. Has become. But,
In the first pattern, the number of characters of the barcode 1 demodulated including the light guide bar RGB by the scanning line A2 is 3, whereas in the second pattern, the demodulation including the light guide bar RGB is performed by the scanning line A2. The number of characters of barcode 1 is 5. That is, the overlapping position of the first pattern is closer to the light guide bar RGB side than the second pattern.

When the number of characters of the bar code 1 demodulated including the light guide bar RGB is small, the light guide bar RGB may be erroneously read by the newspaper column display as described above. Therefore, in the third embodiment,
The smaller the number of characters of the demodulated data including only the guide bar, that is, the closer the overlapping position is to the guide bar side, the higher the possibility of misreading. Therefore, in order to improve the reliability, the reference number changing unit 37B causes the matching number checking unit 36 to check. Change the setting of the reference number of. At this time, the overlapping position is detected when the above-described character duplication check is performed by the function of the reading state information acquisition unit (overlap position detecting unit) of the data comparison unit 34B.

The operation of the reference number setting changing process by the reference number changing unit 37B will be described with reference to the flowchart (steps S41 to S47) shown in FIG. 10. The overlapping position detected by the data comparison unit 34B is closest to the center bar CB. If the maximum number of characters of the demodulated data including only the guide bar is 6 (YES in step S41), the reference number in the matching number check unit 36 is 1, that is, the barcode 1 to be read is The number of data acquisitions is changed to 1 (step S42).

If the overlapping position detected by the data comparison unit 34B is closer to the guide bar than the center bar CB by one character, and the number of characters of the demodulated data including only the guide bar is 5, (at step S43). Y
In the case of the ES determination; for example, in the case of the above-mentioned second pattern), the reference number in the coincidence number checking unit 36 is set to 2, that is, the number of times the data of the barcode 1 to be read is captured is changed to 2 (step S44).

Further, if the overlapping position detected by the data comparison section 34B is closer to the guide bar than the center bar CB by 2 characters or more, and the number of characters of the demodulated data including only the guide bar is 4 or less (step S4).
If YES in 5), the reference number in the coincidence number checking unit 36 is set to 3, that is, the number of times the data of the barcode 1 to be read is taken in is changed to 3 (step S46).

If NO is determined in step S45 (when it is determined that the number of characters is not 4 or less), it is determined that some kind of error has occurred, and an instruction to reread the barcode 1 is issued (step S45). S47). As described above, according to the third embodiment of the present invention, according to the overlapping position (the number of characters of the demodulated data including the guide bar) which is the reading state information of the barcode 1, the overlapping position is misread near the guide bar. When the possibility is high, the reference number is set large, and when the overlapping position is close to the center bar and the possibility of misreading is low, the reference number is set small.

Therefore, when one bar code 1 is divided into a plurality of parts for scanning and demodulation, it is possible to check the number of coincidences according to the reading state (overlapping position) of the bar code 1. The same effect as the example can be obtained. In the third embodiment described above, as shown in FIG. 10, the reference number changing unit 37B sets the reference number to 1 when the number of characters of the demodulated data including only the guide bar is 6, and the same number is set. If the number is 5, the reference number is 2
However, the present invention is not limited to this numerical value, although the reference number is set to 3 when the number of characters is 4 or less.

Further, in the above-described third embodiment, as shown in FIG. 6, one bar code 1 is replaced with two scanning lines A.
Although the case of reading in the form of being divided into two by 1 and A2 has been described, the present invention is not limited to this and is similarly applied to the case where one barcode 1 is divided into three or more and read. As a result, the same effect as that of the third embodiment can be obtained.

(D) Description of Fourth Embodiment The hardware configuration of the bar code reader as the fourth embodiment of the present invention is exactly the same as that of the first embodiment shown in FIG. Further, the functional configuration of the bar code reading apparatus as the fourth embodiment of the present invention is as shown in FIG.
Although substantially the same as that of the first embodiment, in the fourth embodiment, the functions of the barcode combining unit 33A, the data comparing unit 34C and the reference number changing unit 37C are the same as those of the first embodiment shown in FIG.
The functions of the barcode combining unit 33, the data comparing unit 34, and the reference number changing unit 37 of the embodiment are slightly different. In FIG. 11, the same reference numerals as those used above indicate the same parts, and a description thereof will be omitted.

That is, the barcode synthesizing section 3 of the fourth embodiment.
3A has exactly the same function as that of the barcode synthesizing unit 33 of the first embodiment described above, and the combination pattern of a plurality of portions of the barcode 1 [see FIGS. It has a function as a reading state information acquiring unit (combination pattern detecting unit) that detects the reading state information of the code 1 and notifies the reference number changing unit 37C described later.

Further, the data comparison section 34C of the fourth embodiment.
Has only the same function as the data comparison unit 34 of the first embodiment for checking the character duplication, and does not have the function as the reading state information acquisition means described above in the first to third embodiments. Further, the reference number changing unit (reference number changing unit) 37C of the fourth embodiment is the combination pattern (the reading state of the barcode 1 obtained by the function as the reading state information obtaining unit of the barcode synthesizing unit 33A described above. The predetermined reference number of times in the matching number check unit 36 is changed according to the information). The detailed setting changing operation of the reference number changing unit 37C in the fourth embodiment will be described later with reference to FIG.

The overall operation flow of the fourth embodiment of the present invention configured as described above is exactly the same as that of the first embodiment described according to the flow chart shown in FIG. 4, and therefore the description thereof is omitted. To do. By the way, when the barcode 1 as shown in FIG.
2 (A) to (D) are conceivable, and the barcode composing unit 33A composes / combines a plurality of demodulated data with a combination pattern corresponding to the division pattern.

The division pattern (combination pattern) shown in FIG. 12A is a two-division pattern, and the scanning line A1
The demodulated data according to 1 includes both the guard bar GB and the center bar CB. And the scan line A
The demodulated data by 2 includes only the other guard bar GB, and these demodulated data are overlapped at the shaded portion B1 in the figure.

The division pattern (combination pattern) shown in FIG. 12B is a three-division pattern, and the scanning line A1
The demodulated data according to 1 includes both one guard bar GB and the center bar CB, the demodulated data according to the scanning line A2 includes only the center bar CB, and the demodulated data according to the scanning line A3 includes only the other guard bar GB. Then, the demodulated data by the scanning line A2 and the demodulated data by the scanning line A3 overlap each other in the shaded portion B1 in the figure.

The division pattern (combination pattern) shown in FIG. 12C is also a three-division pattern. In this division pattern, the demodulation data by the scanning line A1 includes only one guard bar GB and the demodulation data by the scanning line A2. Includes only the center bar CB, and the demodulated data by the scan line A3 includes only the other guard bar GB. Then, the demodulated data by the scan line A1 and the demodulated data by the scan line A2 overlap each other in a shaded portion B1 in the figure, and the demodulated data by the scan line A2 and the demodulated data by the scan line A3 in a shaded portion B2 in the figure. It overlaps.

The division pattern (combination pattern) shown in FIG. 12D is a 4-division pattern, and the scanning line A1
The demodulated data by includes only one guard bar GB,
The demodulated data by the scan line A2 includes only the center bar CB, the demodulated data by the scan line A3 includes only the center bar CB, and the demodulated data by the scan line A4 includes only the other guard bar GB. Then, the demodulated data by the scanning line A1 and the demodulated data by the scanning line A2 overlap each other in a hatched portion B1 in the drawing, and
The demodulated data by the scanning line A3 and the demodulated data by the scanning line A4 overlap in a shaded portion B2 in the drawing.

In such a division pattern (combination pattern), the larger the division number (combination number), the smaller the portion of the barcode 1 to be demodulated and the larger the overlapping portion. Get lower. Therefore, in the fourth embodiment, the larger the number of divisions or the number of overlapping portions, the higher the possibility of misreading. Therefore, in order to improve the reliability, FIG.
According to the combination pattern as shown in (D) to (D), the reference number changing unit 37C largely changes the reference number in the matching number checking unit 36. At this time, the combination pattern is detected when the plurality of demodulated data are combined / combined by the function of the reading state information acquisition unit (combination pattern detection unit) of the barcode combining unit 33A.

The operation of the reference number setting changing process by the reference number changing unit 37C will be described with reference to the flowchart (steps S51 to S59) shown in FIG. 13. The combination pattern of demodulated data by the bar code synthesizing unit 33A is shown in FIG. ) Shown in (2) (the number of divisions is 2, the number of overlapping portions is 1) (when YES is determined in step S51), the reference number in the coincidence number checking unit 36 is 1, that is, the data of the barcode 1 to be read. The number of acquisitions is changed to 1 (step S52).

If the combination pattern of the demodulated data by the barcode synthesizing section 33A is the three-division type (division number 3, overlapping portion number 1) shown in FIG. 12B (step S).
In the case of YES in 53), the reference number in the coincidence number checking unit 36 is changed to 2, that is, the number of times the data of the barcode 1 to be read is taken in is changed to 2 (step S54).

Furthermore, if the combination pattern of the demodulated data by the barcode synthesizing unit 33A is the three-division type (division number 3, overlapping portion number 2) shown in FIG. 12C (YES determination in step S55), Matching number check unit 36
The reference number in step 3 is set to 3, that is, the number of times the bar code 1 to be read is taken in is changed to 3 (step S5
6).

Then, if the combination pattern of the demodulated data by the barcode synthesizing unit 33A is the 4-division type (division number 4, overlapping portion number 2) shown in FIG. 12D (YES in step S57), Matching number check unit 36
The reference number in 4 is set to 4, that is, the number of times the data of the barcode 1 to be read is taken in is changed to 4 (step S5).
8).

If the determination in step S57 is NO (if none of the patterns shown in FIGS. 12A to 12D is applied), it is determined that some error has occurred, and the barcode 1 Instruct re-reading (step S
59). As described above, according to the fourth embodiment of the present invention, depending on the combination pattern (division pattern) which is the reading state information of the barcode 1, the number of divisions and the number of overlapping portions of the combination pattern are large and there is a possibility of misreading. When the number is high, the reference number is set large, and when the number of divisions and the number of overlapping portions of the combination pattern are small and the possibility of misreading is low, the reference number is set small.

Therefore, when one bar code 1 is divided into a plurality of parts for scanning and demodulation, the number of coincidences can be checked according to the reading state (combination pattern) of the bar code 1. The same effect as the example can be obtained. In addition, in the above-described fourth embodiment, as shown in FIG.
~ (D) according to each pattern, the reference number of times 1 to 4
However, the present invention is not limited to this numerical value.

(E) Description of Fifth Embodiment The hardware configuration of the bar code reader as the fifth embodiment of the present invention is exactly the same as that of the first embodiment shown in FIG. Further, the functional configuration of the barcode reading apparatus as the fifth embodiment of the present invention is as shown in FIG.
Although substantially the same as that of the first embodiment, in the fifth embodiment, the function of the reference number changing unit 37D is slightly different from the function of the reference number changing unit 37 of the first embodiment shown in FIG. A strain amount measuring unit 39 is newly provided. In addition,
In FIG. 14, the same reference numerals as those used above indicate the same parts, and a description thereof will be omitted.

That is, the distortion amount measuring section (reading state information acquiring means, distortion amount measuring means) 39 of the fifth embodiment, based on the demodulation result by the bar code demodulating section 32, reads the bar code 1 dividedly. Is calculated and measured as the reading state information of the bar code 1, and is notified to the reference number changing unit 37D described later. A specific example of the reading distortion amount measured by the distortion amount measuring unit 39 will be described later with reference to FIGS.

Further, the reference number changing section (reference number changing means) 37D of the fifth embodiment responds to the read strain amount (reading state information of the bar code 1) measured by the strain amount measuring unit 39 described above. The predetermined reference number of times in the matching number check unit 36 is set and changed. The detailed setting changing operation of the reference number changing unit 37D in the fifth embodiment will be described later with reference to FIG.

The overall operation flow of the fifth embodiment of the present invention configured as described above is exactly the same as that of the first embodiment described according to the flow chart shown in FIG. 4, so the description thereof is omitted. To do. By the way, when the barcode 1 is divided and read, as described above, the partial data including at least one of the center bar and the two guard bars is demodulated as much as possible, and several characters obtained for each partial data are used. 1 by combining demodulated data
It demodulates and reads one bar code.

The character just before being unable to perform demodulation may have erroneously read a character, paper surface noise, or the like as a bar code. Such a character having a high possibility of misreading inevitably has a large reading distortion amount. Therefore,
It is desired that the larger the reading distortion amount, the larger the predetermined reference number in the coincidence number checking unit 36 is set to improve the reliability of the divided reading result.

Here, as the reading distortion amount of the bar code 1, the distortion amount of the character length, the distortion amount of the δ distance length, or the distortion amount of the bar itself can be considered. First, a case where the distortion amount of the character length is measured as the reading distortion amount of the barcode 1 will be described. At this time, FIG.
As shown in (A), when the character length of a portion where a plurality of portions of the barcode 1 overlap with each other is C2 and the character length of portions other than the overlapping portion is C1, the distortion amount measuring unit 39.
Is a character length distortion amount of a portion where a plurality of portions of the barcode 1 overlap each other, based on the character lengths C1 and C2 obtained at the time of demodulation by the barcode demodulation unit 32.
/ C1 is calculated and measured. The distortion amount C2 / C1 of the character length is calculated in each of the two overlapping portions, and the largest distortion amount is notified to the reference number changing unit 37D as the reading distortion amount.

Then, the reference number changing unit 37D has a distortion amount of, for example, 0.9 to 1.1 as shown in FIG.
If it is within the range, the distortion amount is determined to be small (YES determination in step S61 of FIG. 18), and the reference number in the coincidence number check unit 36 is 1, that is, the number of data acquisitions of the barcode 1 to be read. While changing the setting to 1 (Fig. 1
8 step S62), and the distortion amount is shown in FIG.
As shown in, for example, 0.875 to 0.9 or 1.1
If it is within the range from 1.125 to 1.125, it is determined that the amount of distortion is large (NO determination in step S61 of FIG. 18), the reference number of times by the coincidence number checking unit 36 is 2, that is, the barcode 1 to be read. The number of times the data is captured is changed to 2 (see step S63 in FIG. 18). Note that FIG. 15B
In, the distortion amount is shown as a coefficient of the character length C1.

Next, as the reading distortion amount of the bar code 1, δ
The case of measuring the strain amount of the distance length will be described. When the barcode demodulation unit 32 performs the demodulation processing of the barcode data, as shown in FIG.
Two δ distance lengths T1 and T as shown in 6 (A)
Characters are discriminated based on the combination of two modules.

Therefore, in the case of measuring the distortion amount of the δ distance length as the reading distortion amount, the distortion amount measuring unit 39 is a portion where a plurality of portions of the barcode 1 obtained at the time of demodulation by the barcode demodulating unit 32 overlap each other. Δ distance lengths T1, T2 of T divided by the character length C, T1 / C,
Calculate and measure T2 / C as the reading distortion amount. The distortion amounts T1 / C and T2 / C of the δ distance length are calculated in each of the two overlapping portions and are notified to the reference number changing unit 37D.

Then, the reference number changing unit 37D determines that the distortion amount is large when the distortion amount is within the range shown by the diagonal lines in FIG. 16B (step S in FIG. 18).
(NO determination in 61), the reference number in the coincidence number check unit 36 is set to 2, that is, the number of times the data of the barcode 1 to be read is taken in is changed to 2 (step S63 in FIG. 18).
16), if the distortion amount is outside the range shown by the diagonal lines in FIG. 16B, it is determined that the distortion amount is small (FIG. 1).
(YES determination in step S61 of 8), the reference number in the coincidence number checking unit 36 is set to 1, that is, the number of times of data acquisition of the barcode 1 to be read is changed to 1 (see step S62 in FIG. 18).

Next, the case where the distortion amount of the bar itself is measured as the reading distortion amount of the bar code 1 will be described. When performing the demodulation processing of the bar code data by the bar code demodulation unit 32, as described above, the character discrimination is performed based on the combination of the number of modules of the two δ distance lengths T1 and T2 as shown in FIG. 16 (A). I'm doing
There are characters that cannot be distinguished by these δ distance lengths T1 and T2. In such a case, the bar code demodulation unit 32 causes the length of each bar itself [Fig. 17 (A)].
A, b, c, d] are obtained, the number of modules of each bar itself is calculated, and character discrimination is performed.

Therefore, in the case of measuring the distortion amount of the bar itself as the reading distortion amount, the distortion amount measuring unit 39 detects a portion of a plurality of portions of the bar code 1 which are obtained at the time of demodulation by the bar code demodulating unit 32 and overlap each other. Values a / C to d / C obtained by dividing the lengths a to d of the bars themselves by the character length C are calculated and measured as the reading distortion amount. The distortion amount a / of each bar itself
C to d / C are calculated in each of the two overlapping portions and are notified to the reference number changing unit 37D.

Then, as in the case where the distortion amount of the δ distance length is used as the reading distortion amount, the reference number changing unit 37D determines that the distortion amount is within the range shown by the shaded area in FIG. 17B. , It is determined that the amount of distortion is large (NO determination in step S61 of FIG. 18), and the reference number of times in the coincidence number checking unit 36 is set to 2, that is, the number of times of data acquisition of the barcode 1 to be read is changed to 2 ( Step S of FIG.
63), and if the distortion amount is outside the range shown by the diagonal lines in FIG. 16B, it is determined that the distortion amount is small (YES determination in step S61 of FIG. 18), and the matching number check unit 36 The reference number in step 1 is changed to 1, that is, the number of times the data of the barcode 1 to be read is captured is changed to 1 (see FIG.
8 step S62).

As described above, according to the fifth embodiment of the present invention, according to the reading distortion amount which is the reading state information of the bar code 1, when the reading distortion amount is large and the possibility of erroneous reading is high, the reference number of times is set. Is set to a large value, and when the reading distortion amount is small and the possibility of erroneous reading is low, the reference number is set to a small value. Therefore, when one bar code 1 is divided into a plurality of parts for scanning and demodulation, it is possible to check the number of coincidences according to the reading state (reading distortion amount) of the bar code 1 and the first embodiment. The same effect can be obtained.

In the fifth embodiment described above, as shown in FIG. 18, the reference number changing unit 37D sets the reference number to 2 when the reading distortion amount is large, and when the reading distortion amount is small. Although the example in which the reference number is set to 1 has been described in the above, the present invention is not limited to this numerical value, and the reading distortion amount is finely classified and the reference number is set for each reading distortion amount. You may

(F) Description of Sixth Embodiment The hardware configuration of the bar code reader as the sixth embodiment of the present invention is exactly the same as that of the first embodiment shown in FIG. Further, the functional configuration of the barcode reading apparatus as the sixth embodiment of the present invention is as shown in FIG.
Although it is almost the same as that of the first embodiment, in the sixth embodiment, the function of the reference number changing unit 37E is slightly different from the function of the reference number changing unit 37 of the first embodiment shown in FIG. A bit shift data detection unit 40 is newly provided. In FIG. 19, the same reference numerals as those used above indicate the same parts, and a description thereof will be omitted.

That is, the bit shift data detecting section (reading state information obtaining means, bit shift data detecting means) 40 of the sixth embodiment, based on the demodulation result by the bar code demodulating section 32, demodulates a plurality of barcodes 1. Information on whether or not the data can be different data when bit-shifted (bit shift data) is detected as the reading status information of the barcode 1, and the reference number changing unit 3 to be described later.
It is output to 7E. The bit shift data will be described later with reference to FIGS.

Further, the reference number changing unit (reference number changing unit) 37E of the sixth embodiment is matched according to the information (reading state information of the bar code 1) detected by the bit shift data detecting unit 40 described above. The predetermined number of times of reference in the frequency check unit 36 is changed. In addition,
The detailed setting changing operation of the reference number changing unit 37E in the sixth embodiment will be described later with reference to FIG.

The overall operation flow of the sixth embodiment of the present invention configured as described above is exactly the same as that of the first embodiment described according to the flow chart shown in FIG. 4, and therefore the description thereof is omitted. To do. By the way, when one bar code 1 is divided into a plurality of parts and read as described above,
In addition to the demodulated data whose end positions are defined by the guard bar and the center bar, there is demodulated data that includes only the center bar and one of the two guard bars.
Such demodulated data may become different demodulated data when bit shifting is performed. For example, FIG. 20 (A)
The data shown in FIG. 20B and FIG. 20B includes the center bar CB, but two types of demodulation, the upper stage and the lower stage in the figure, are possible. The reference numerals in FIGS. 20A and 20B correspond to those shown in FIG.

It is difficult to determine which of the two types of demodulation results of such bit shift data is correct, and when such bit shift data occurs,
Since the reliability of the demodulated data of the barcode 1 is low, it is desired to increase the predetermined reference number in the coincidence number checking unit 36 to improve the reliability of the divided reading result.

Therefore, in the sixth embodiment, if the bit shift data detection unit 40 detects that the bit shift data has been obtained as the demodulated data by the bar code demodulation unit 32, there is a high possibility of erroneous reading, so reliability is improved. In order to increase the number of times, the reference number changing unit 37E uses the matching number checking unit 3
The reference number in 6 is largely changed. The operation of the reference number setting changing process by the reference number changing unit 37E will be described with reference to FIG.
According to the flowchart shown in FIG. 1 (steps S71 to S73), when the bit shift data detection unit 40 detects bit shift data (step S71).
In the case of YES determination), the reference number in the coincidence number checking unit 36 is set to 2, that is, the data capturing number of the barcode 1 to be read is set to 2 (step S72). Then, while no bit shift data is detected by the bit shift data detection unit 40 (NO determination in step S71), the reference number of times by the coincidence number check unit 36 is set to 1,
In other words, the number of data acquisitions of barcode 1 to be read is 1
The setting is changed to (step S73).

As described above, according to the sixth embodiment of the present invention, the demodulated data is bit shift data according to the presence / absence information of the bit shift data which is the reading state information of the bar code 1, and there is a high possibility of misreading. In this case, the reference number is set large, and when the demodulated data is not bit shift data and the possibility of misreading is low, the reference number is set small.

Therefore, when one bar code 1 is divided into a plurality of parts for scanning and demodulation, it is possible to check the number of coincidences according to the reading status of the bar code 1 (information on the presence or absence of bit shift data). The same effect as that of the first embodiment can be obtained. In the sixth embodiment described above, as shown in FIG. 21, the reference number changing unit 37E sets the reference number to 1 when there is no bit shift data, and sets the reference number when there is bit shift data. Although the example of setting to 2 has been described, the present invention is not limited to this numerical value.

(G) Description of Seventh Embodiment The hardware configuration of the bar code reading apparatus as the seventh embodiment of the present invention is exactly the same as that of the first embodiment shown in FIG. Further, the functional configuration of the barcode reading apparatus as the seventh embodiment of the present invention is as shown in FIG.
Although substantially the same as that of the first embodiment, in the seventh embodiment, the function of the reference number changing unit 37F is slightly different from the function of the reference number changing unit 37 of the first embodiment shown in FIG. , And a wave error detector 41 is newly provided. In FIG. 22, the same reference numerals as those used above indicate the same parts, and a description thereof will be omitted.

That is, the wave error detector of the seventh embodiment (reading state information acquisition means, wave error detection means).
The reference numeral 41 detects information as to whether or not a wave error has occurred in a plurality of demodulated data of the barcode 1 as the reading state information of the barcode 1 based on the demodulation result by the barcode demodulation unit 32, and a standard to be described later. This is output to the frequency changing unit 37F.

Here, the wave error will be briefly described. When reading the barcode 1, the black edge signal and the white edge signal are detected by performing the differential processing and the delay processing on the analog signal as the light and dark information corresponding to the white bar 1W and the black bar 1B. ing. In the barcode 1, the white bars 1W and the black bars 1B are always arranged alternately, so that the black edge signal and the white edge signal described above appear alternately. However, if some noise component is included in the brightness information due to paper surface noise or the like, a phenomenon may occur in which the black edge signal and the white edge signal cannot be obtained alternately. Such a phenomenon is called a wave error.

Further, the reference number changing unit (reference number changing unit) 37F of the seventh embodiment uses the wave error occurrence information (bar code 1 reading status information) detected by the wave error detecting unit 41 described above. Accordingly, the predetermined reference number of times in the matching number check unit 36 is set and changed. The detailed setting changing operation of the reference number changing unit 37F in the seventh embodiment will be described later with reference to FIG.

The overall operation flow of the seventh embodiment of the present invention configured as described above is exactly the same as that of the first embodiment described according to the flow chart shown in FIG. 4, and therefore its description is omitted. To do. By the way, a character that cannot be demodulated by the bar code demodulation unit 32 causes a wave error as described above due to paper surface noise or the like, and the demodulated data cannot be regarded as valid data. Also,
Since the character adjacent to the portion where the wave error has occurred is likely to have been erroneously demodulated such as a character or paper surface noise, that is, there is a high possibility of misreading, the reliability of the barcode 1 is low. Therefore, when a wave error occurs in the demodulated data, it is desirable to increase the predetermined reference number in the coincidence number checking unit 36 to improve the reliability of the divided reading result.

For example, as in the case of the first embodiment shown in FIG. 6, one bar code 1 is used for two scanning lines A1, A.
Consider the case where the data is divided into two parts and read by step 2. Here, in the first pattern, the scan line A
The characters of barcode 1 demodulated by 1 are AF,
The characters of the barcode 1 demodulated by the scanning line A2 in G, H, and I are the adjacent portions of the character I in I, J, K, and L (the character H of the demodulated data by the scanning line A1.
It is assumed that a wave error has occurred at the position (overlapping with). In the second pattern, the characters of the barcode 1 demodulated by the scan line A1 are A to F, G, and
Bar code 1 demodulated by scan line A2 with H and I
It is assumed that the characters are I, J, K and L and no wave error has occurred.

At this time, in the first pattern, when a wave error occurs in the character of the demodulated data by the scan line A2 after demodulation of the character I and the character I cannot be demodulated, the character I is erroneous in characters or paper surface noise. Since the character I may have been demodulated, the reliability of the character I becomes low. In addition, since the wave error does not occur in the second pattern, rather than the character I in the demodulated data by the scan line A2 of the first pattern,
The reliability of the character I of this second pattern is higher.

Therefore, in the seventh embodiment, when the wave error detecting section 41 detects that a wave error has occurred in the demodulated data by the bar code demodulating section 32,
Since the possibility of erroneous reading is high, the reference number change unit 37F largely changes the reference number in the matching number check unit 36 in order to improve reliability. The operation of the reference number setting changing process by the reference number changing unit 37F will be described according to the flowchart (steps S81 to S83) shown in FIG. 23. When the wave error detection unit 41 detects a wave error (YES determination in step S81). In the case of), the reference number in the coincidence number checking unit 36 is changed to 2, that is, the number of times the data of the barcode 1 to be read is taken in is changed to 2 (step S82). Then, while the wave error detection unit 41 does not detect a wave error (when NO is determined in step S81), the reference number in the coincidence number check unit 36 is 1, that is, the data acquisition number of the barcode 1 to be read is 1. The setting is changed to (step S83).

As described above, according to the seventh embodiment of the present invention, there is a high possibility that a wave error will occur in the demodulated data depending on the wave error presence / absence information, which is the read status information of the bar code 1, and erroneous reading will occur. In this case, the reference number is set large, and when there is no wave error in the demodulated data and the possibility of misreading is low, the reference number is set small. Therefore, one barcode 1 is divided into a plurality of parts for scanning,
When demodulating, the number of coincidences can be checked according to the reading state of the bar code 1 (waveform error presence / absence information), and the same effect as the first embodiment can be obtained.

In the seventh embodiment described above, as shown in FIG. 21, the reference number changing unit 37F sets the reference number to 1 when there is no wave error, and the reference number when there is a wave error. However, the present invention is not limited to this numerical value. Further, in the above-described seventh embodiment, as shown in FIG. 6, one bar code 1 is used for two scanning lines A1, A2.
However, the present invention is not limited to this and is similarly applied to the case where one barcode 1 is divided into three or more and read. The same effect as that of the seventh embodiment can be obtained.

(H) Description of Eighth Embodiment The hardware configuration of the bar code reader as the eighth embodiment of the present invention is exactly the same as that of the first embodiment shown in FIG. The functional configuration of the barcode reading apparatus as the eighth embodiment of the present invention is as shown in FIG.
Although substantially the same as that of the first embodiment, in the eighth embodiment, the functions of the barcode data detection unit 31A and the reference number change unit 37G are the same as those of the first embodiment shown in FIG. The functions of the unit 31 and the reference number changing unit 37 are slightly different. In FIG. 24, the same reference numerals as those used above indicate the same parts, and a description thereof will be omitted.

That is, the bar code data detecting section (reading state information acquiring means, guard bar / center bar detecting means) 31A of the eighth embodiment has the same function as the bar code data detecting section 31 of the first embodiment. , The information indicating whether or not there is a part including both the guard bar and the center bar of the bar code 1 among the plurality of parts of the bar code 1 that has been divided and read is detected as the reading state information of the bar code 1, and will be described later. It has a function of outputting to the reference number changing unit 37F.

The reference number changing unit (reference number changing unit) 37G of the eighth embodiment is matched according to the information (reading state information of the barcode 1) detected by the barcode data detecting unit 31A described above. The predetermined number of times of reference in the frequency check unit 36 is changed. In addition,
The detailed setting changing operation of the reference number changing unit 37G in the eighth embodiment will be described later with reference to FIG.

The overall operation flow of the eighth embodiment of the present invention configured as described above is exactly the same as that of the first embodiment described according to the flow chart shown in FIG. 4, and therefore the description thereof is omitted. To do. By the way, when one bar code 1 is divided into a plurality of parts and read as described above,
The data demodulated by the scan line passing only the guide bar or the center bar is likely to be bit shift data as described in the sixth embodiment, but
Since the data demodulated by the scanning line passing through both the guide bar and the center bar is unlikely to be bit shift data, the reliability of the demodulated data also becomes high.

For example, as shown in FIG. 25, scan line A
The character code of the barcode 1 demodulated by 1 (passes through both the left guide bar LGB and the center bar CB) is A to F, G, H, and I, and is demodulated by the scanning line A2 (passes only the right guide bar RGB). Barcode 1
The characters are I, J, K, L, and the bar code 1 demodulated by the scanning line A3 (only the center bar CB passes)
Characters are E, F, G, H, I, and scanning line A4
Characters of the barcode 1 demodulated by (passing only the left guide bar LGB) are assumed to be A, B, C, D, and E.

At this time, in the first pattern, the data is combined with the character demodulated by the two scanning lines A1 and A2, and in the second pattern, the three scanning lines A2 to A2.
Assuming that the data is synthesized with the character demodulated by 4, the demodulated data of the second pattern is data including only the guard bar or the center bar, and the reliability is low as described above. However, the demodulated data of the first pattern is less likely to be erroneously read because only the data demodulated by the scanning line A2 has low reliability and the data demodulated by the scanning line A1 has high reliability.

Therefore, in the eighth embodiment, if the portion including both the guard bar and the center bar of the bar code 1 is not detected by the bar code data detecting section 31A, there is a high possibility of erroneous reading, and therefore the reliability is high. To increase
The reference number changing unit 37G largely changes the reference number in the matching number checking unit 36. The operation of the reference number setting changing process by the reference number changing unit 37G will be described according to the flowchart (steps S91 to S93) shown in FIG. 26.
When a portion of the barcode 1 including both the guard bar and the center bar is detected (YES in step S91), the reference number in the match number check unit 36 is set to 1,
In other words, the number of data acquisitions of barcode 1 to be read is 1
The setting is changed to (step S92). If the barcode data detection unit 31A does not detect a portion of the barcode 1 that includes both the guard bar and the center bar (NO in step S91), the reference count in the match count check unit 36 is set to 2 That is, the number of data acquisitions of the barcode 1 to be read is changed to 2 (step S93).

As described above, according to the eighth embodiment of the present invention, according to the presence / absence information of the guard bar / center bar which is the reading status information of the bar code 1, the demodulation processing based on the data including only the guard bar or the center bar can be performed. When the possibility of misreading is high, the reference number is set large, and when the probability of misreading is low in the demodulation process based on the data including both the guard bar and the center bar, the reference number is set small.

Therefore, when one bar code 1 is divided into a plurality of parts for scanning and demodulation, it is possible to check the number of coincidences according to the read state of the bar code 1 (guard bar / center bar presence / absence information). Therefore, the same effect as that of the first embodiment can be obtained. In the eighth embodiment described above, as shown in FIG. 26, the reference number changing unit 37G
Sets the reference count to 1 when the demodulation process is based on data that includes both the guard bar and the center bar, and sets the reference count to 2 when the demodulation process is based on data that includes only the guard bar or the center bar. However, the present invention is not limited to this numerical value.

(I) Others In each of the above-described embodiments, the bar code to be read is of the type shown in FIG. 6 (right and left guide bars LGB, R).
In addition to the GB, the center bar CB is provided in the center, and the type having six characters between the center bar CB and each of the guide bars LGB, RGB has been described. The present invention is not limited to this, and is applied to the type having the special center bar SCB shown in FIG. 28 and other various bar code readings, and the same effect as each of the above-described embodiments can be obtained. You can

Further, a plurality of reading status information of the bar code 1 described in each of the first to eighth embodiments may be combined to set and change the reference number of times in the coincidence number checking section 36. The following are conceivable examples of specific combinations. The reference number of times in the matching number check unit 36 is changed according to the character length distortion amount as the reading distortion amount described in the fifth embodiment, the δ distance length distortion amount, and the distortion amount of each bar itself. Method to do.

In accordance with the overlapping position described in the third embodiment and the three types of reading distortion amounts described in the fifth embodiment,
A method of changing and setting the reference number of times in the match number checking unit 36. A method of setting and changing the reference number of times in the matching number check unit 36 according to the number of overlapping characters described in the first example and the overlapping position described in the third example.

Depending on the number of non-matching characters described in the second embodiment and the overlapping position described in the third embodiment,
A method of changing and setting the reference number of times in the match number checking unit 36. A method of changing and setting the reference number of times in the matching number check unit 36 according to the number of duplicate characters described in the first example and the bit shift data presence / absence information described in the sixth example.

A method of setting and changing the reference number of times in the coincidence number checking unit 36 according to the overlapping position described in the third embodiment and the wave error presence / absence information described in the seventh embodiment.

[0174]

As described above in detail, according to the barcode reading method and the barcode reading apparatus of the present invention, the reference number is increased according to the reading status information of the barcode when the possibility of erroneous reading is high. If it is set and the possibility of erroneous reading is low, the reference number can be set to a small value, so that the reading rate in actual operation can be significantly improved and the erroneous reading rate can be greatly reduced without lowering the reading efficiency. There is.

[Brief description of drawings]

FIG. 1 is a principle block diagram of the present invention.

FIG. 2 is a block diagram showing a hardware configuration of a barcode reading apparatus as a first embodiment of the present invention.

FIG. 3 is a block diagram showing a functional configuration of a barcode reading apparatus as a first embodiment of the present invention.

FIG. 4 is a flowchart for explaining the flow of the overall operation of the first embodiment of the present invention.

FIG. 5 is a flowchart for explaining a reference number setting operation in the first embodiment of the present invention.

FIG. 6 is a diagram for explaining an example of a barcode structure and an overlapping state of divided read data according to the present embodiment.

FIG. 7 is a block diagram showing a functional configuration of a barcode reading apparatus as a second embodiment of the present invention.

FIG. 8 is a flow chart for explaining a reference number setting operation in the second embodiment of the present invention.

FIG. 9 is a block diagram showing a functional configuration of a bar code reading apparatus as a third embodiment of the present invention.

FIG. 10 is a flow chart for explaining a reference number setting operation in the third embodiment of the present invention.

FIG. 11 is a block diagram showing a functional configuration of a bar code reading device as a fourth embodiment of the present invention.

12A to 12D are diagrams showing division patterns (combination patterns) at the time of divided reading of a barcode.

FIG. 13 is a flow chart for explaining a reference number setting operation in the fourth example of the present invention.

FIG. 14 is a block diagram showing a functional configuration of a bar code reading device as a fifth embodiment of the present invention.

15A and 15B are diagrams for explaining a method of determining a distortion amount of character length in the fifth embodiment.

16A and 16B are diagrams for explaining a method of determining the distortion amount of the δ distance length in the fifth embodiment.

17 (A) and 17 (B) are views for explaining a method of determining the distortion amount of the bar itself in the fifth embodiment.

FIG. 18 is a flow chart for explaining a reference number setting operation in the fifth embodiment of the present invention.

FIG. 19 is a block diagram showing a functional configuration of a bar code reading device as a sixth embodiment of the present invention.

20A and 20B are diagrams showing an example of bit shift in the sixth embodiment.

FIG. 21 is a flow chart for explaining a reference number setting operation in the sixth embodiment of the present invention.

FIG. 22 is a block diagram showing a functional configuration of a bar code reading device as a seventh embodiment of the present invention.

FIG. 23 is a flow chart for explaining a reference number setting operation in the seventh embodiment of the present invention.

FIG. 24 is a block diagram showing a functional configuration of a bar code reading device as an eighth embodiment of the present invention.

FIG. 25 is a diagram showing an example of divided scanning when reading a barcode.

FIG. 26 is a flow chart for explaining the reference number setting operation in the eighth embodiment of the present invention.

FIG. 27 is a block diagram showing a configuration of a general barcode reading device.

FIG. 28 is a diagram showing a configuration of a general barcode.

FIG. 29 is a table showing a relationship between a combination of module numbers and numerical data.

FIG. 30 is a diagram showing a configuration of a general barcode.

FIG. 31 is a diagram showing a general scanning example when reading a barcode.

FIG. 32 is a diagram illustrating an example of divided scanning when reading a barcode.

[Explanation of symbols]

1 Bar Code 1B Black Bar 1W White Bar 2 Optical System 3 Laser Light Emitting Unit (Light Source) 3A Light Source 4 Scanning Mechanism (Scanning Means) 4A Scanning Means 5 Photoelectric Converter (Photoelectric Converting Means) 5A Photoelectric Converting Means 6 A / D Converting Means 7 bar width counter 8 clock generator 9 memory 10 CPU 11 demodulation means 12 combination means 13 coincidence number determination means 14 read state information acquisition means 15 reference number change means 21 ROM 22 RAM 22A demodulated data storage section 23 interface section 24 control section circuit 25 Motor drive unit 26 Laser drive unit 27 Light emitting diode (LED) 28 Speaker 31 Bar code data detection unit 31A Bar code data detection unit (reading state information acquisition unit, guard bar / center bar detection unit) 32 Bar code demodulation unit (demodulation unit) 33 Bar code synthesis section Combining means) 33A bar code combining unit (combination means, the reading state information acquiring unit, a combination pattern detecting means) 34 or 34A data comparison unit (reading state information acquiring means,
Character number detection means) 34B Data comparison section (reading state information acquisition means, overlap position detection means) 34C Data comparison section 35 Modulus 10 check section 36 Match count check section (match count judgment section) 37, 37A to 37G Reference count change section (Reference number changing means) 38 Bar code reading completion notifying section 39 Distortion amount measuring section (reading state information acquiring means, distortion amount measuring means) 40 Bit shift data detecting section (reading state information acquiring means, bit shift data detecting means) 41 Wave error detector (reading status information acquisition means,
Wave error detection means)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Isao Iwaguchi 1015 Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture, Fujitsu Limited (72) Inventor, Hiroaki Kawai, 1015, Kamikodanaka, Nakahara-ku, Kawasaki, Kanagawa Prefecture, Fujitsu Limited (72) Inventor Motohiko Ito 1015 Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture, Fujitsu Limited (72) Inventor Ichiro Shinoda 1015, Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture, Fujitsu Limited

Claims (24)

[Claims] 1. A bar code is irradiated with a plurality of light beams, the bar code is scanned by each light beam, and each light beam is scanned based on the amount of light reflected from the bar code. By demodulating data for a plurality of portions of the barcode that are partially scanned by, and combining demodulated data for a plurality of portions of the barcode to demodulate the data of the barcode. Is a bar code reading method in which the data demodulated from the barcode is validated and the reading of the barcode is completed when the data is continuously demodulated a predetermined number of times, A bar code reading method, wherein the setting is changed according to the bar code reading status information. 2. The bar code according to claim 1, wherein the number of characters demodulated in duplicate in demodulation data for a plurality of parts of the bar code is used as the reading status information of the bar code. How to read. 3. The bar code reading status information is characterized in that the number of characters having different demodulation results is used in overlapping parts in demodulation data of a plurality of parts of the bar code. Barcode reading method. 4. The barcode reading method according to claim 1, wherein positions of overlapping portions in demodulated data of a plurality of portions of the barcode are used as the barcode reading state information. 5. The barcode reading method according to claim 1, wherein a combination pattern of demodulated data for a plurality of portions of the barcode is used as the reading status information of the barcode. 6. The barcode reading method according to claim 1, wherein a reading distortion amount of a portion where a plurality of portions of the barcode overlap each other is used as the reading state information of the barcode. 7. The barcode reading method according to claim 6, wherein a distortion amount of a character length of a portion where a plurality of portions of the barcode overlap each other is used as the reading distortion amount. 8. As the reading distortion amount, δ is obtained for each character so as to specify character data of a portion where a plurality of portions of the barcode overlap each other.
7. The barcode reading method according to claim 6, wherein a distortion amount of a distance length is used. 9. The barcode reading method according to claim 6, wherein the reading distortion amount is a distortion amount of a bar itself forming a character of a portion where a plurality of portions of the barcode overlap each other. . 10. The bar code reading status information is information on whether or not data in a plurality of portions of the bar code can be different data when bit shift is performed. The barcode reading method according to claim 1. 11. The barcode reading method according to claim 1, wherein presence or absence of a wave error in a plurality of portions of the barcode is used as the barcode reading status information. 12. As the bar code reading status information, information on whether or not a plurality of parts of the bar code have detected both a guard bar and a center bar of the bar code is used. Claim 1 characterized by
Barcode reading method described. 13. A light source that emits light beams, a scanning unit that irradiates a plurality of light beams from the light sources onto a bar code, and scans the bar code with each light beam, and a scanning unit for each light beam. Photoelectric conversion means for receiving the reflected light from the bar code and converting it into an electric signal corresponding to the quantity of the light, and of the bar code partially scanned by each light beam based on the electric signal from the photoelectric conversion means. Demodulation means for demodulating data of a plurality of parts, combining means for demodulating data of the bar code by combining demodulation data of a plurality of parts of the barcode demodulated by the demodulation means, and the demodulation means and The combination means detects the number of times the same data is continuously demodulated from the barcode, compares the number of times with a predetermined reference number of times, and the number of times is the predetermined reference number. The number of coincidence determination means for validating the data demodulated from the bar code to complete the reading of the bar code, and the reading status information acquiring means for acquiring the reading status information of the bar code, A bar is provided with reference number changing means for setting and changing the reference number in the coincidence number determining means in accordance with the reading state information of the bar code acquired by the reading state information acquiring means. Code reader. 14. The character number detecting means, wherein the reading status information acquiring means detects, as the reading status information of the bar code, the number of characters demodulated in duplicate in the demodulated data of a plurality of parts of the bar code. The bar code reader according to claim 13, wherein the bar code reader is provided. 15. The number-of-characters detection means for detecting the number of characters having different demodulation results in the duplicated portions of the demodulated data of the plurality of portions of the bar code, as the reading state information of the bar code. 14. The barcode reading device according to claim 13, which is a means. 16. The reading status information acquiring means is an overlapping position detecting means for detecting positions of overlapping parts in demodulated data of a plurality of parts of the barcode as reading status information of the barcode. The barcode reader according to claim 13, wherein 17. The reading state information obtaining means is a combination pattern detecting means for detecting a combination pattern of demodulated data of a plurality of portions of the barcode by the combining means as reading state information of the barcode. 14. The bar code reader according to claim 13, which is characterized in that: 18. The distortion amount measuring means for calculating and measuring the reading distortion amount of a portion where a plurality of portions of the barcode overlap each other as the reading state information of the barcode. 14. The bar code reading device according to claim 13, wherein 19. The bar code reader according to claim 18, wherein the distortion amount measuring means calculates and measures a distortion amount of a character length of a portion where a plurality of portions of the barcode overlap each other. . 20. The distortion amount measuring means calculates and measures an amount of distortion of a δ distance length obtained for each character in order to specify character data of a portion where a plurality of portions of the barcode overlap each other. Claim 1 characterized by the above.
8. The bar code reader according to item 8. 21. The bar according to claim 18, wherein the distortion amount measuring means calculates and measures an amount of distortion of the bar itself forming a character of a portion where a plurality of portions of the barcode overlap each other. Code reader. 22. Information on whether or not the data in a plurality of portions of the bar code can be different data when bit-shifted is performed by the read state information acquisition means as the bar code read state information. A bit shift data detecting means for outputting,
The barcode reading device according to claim 13. 23. The reading status information obtaining means is a wave error detecting means for outputting the presence or absence of a wave error in a plurality of portions of the bar code as the reading status information of the bar code. The barcode reading device according to claim 13. 24. Information on whether or not the reading state information obtaining means detects one of a plurality of portions of the barcode that has detected both a guard bar and a center bar of the barcode, 14. The bar code reading device according to claim 13, which is a guard bar / center bar detection unit that outputs the reading state information.