JPH0554167A - Bar code detector - Google Patents

Abstract

(57) [Summary] [Object] To increase the scanning speed of a laser beam and the reading speed of a bar code in a bar code detecting device having a small truncation (bar height), for example, a bar code having a truncation of 11 mm. [Structure] Laser light sources 1a and 1b included in a bar code detection device and a laser beam 4 for collecting laser light.
Focusing means 2a, 2b for emitting a, 4b, scanning means 6 for scanning the laser beams 4a, 4b, and light receiving means 8a, 8 for converting the reflected light from the bar code 7 into an electric signal.
b, and signal processing means 9a, 9b for processing electrical signals and recognizing barcodes, laser light sources 1a, 1b, focusing means 2a, 2b, light receiving means 8a, 8b, and signal processing means 9a, 9b. And plural are provided respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bar code detecting device used in POS, physical distribution, production control and the like.

[0002]

2. Description of the Related Art A conventional bar code detecting device comprises a single He-Ne laser tube that emits a laser beam and a set of three spherical lenses that condense the laser beam and generate a laser beam. A scanning means for scanning the laser beam, one light receiving means for receiving the reflected light from the bar code of the scanning laser beam and converting it into an electric signal, and processing the electric signal output from the light receiving means. It is composed of one signal processing means for recognizing a barcode.

FIG. 2 is a diagram showing the configuration of a conventional bar code detecting device. A laser beam generator 1 including a He-Ne laser tube 11 and a three-lens spherical lens group 12.
3 emits a laser beam 4. The emitted laser beam 4 is reflected and guided by the reflection mirror group 14, passes through the central hole of the concave mirror 5 having a central hole, and is scanned by the polygon mirror 6. The laser beam 4 scans the bar code 7, and the reflected light from the bar code 7 follows the same path as the emitted laser beam 4, is reflected by the polygon mirror 6, and reaches the concave mirror 5. Here, the reflected light is condensed on the PIN photodiode 8 by the concave mirror 5. The PIN photodiode 8 converts the received light signal into an electric signal. The signal processing means 9 processes and decodes the electric signal to detect the bar code. The detected result is sent to the communication means 10. The communication means 10 communicates the barcode code detected based on the result sent from the signal processing means 9 to the host computer.

[0004]

Conventionally, most of the bar codes with a truncation (bar height) of 18 mm or more have been used in the past, but in recent years, the truncation of bar codes has become smaller, and bar codes with a truncation of 11 mm have been standardized. I am trying to do. When the truncation of the bar code is reduced, the probability of the laser beam crossing the bar code while the bar code is being passed within the reading range of the bar code detection apparatus is reduced, which causes a problem that the bar code reading rate is reduced. In order to increase the probability that the laser beam crosses the bar code, it is necessary to increase the laser beam scanning speed of the bar code detection device (the number of times of scanning within a fixed time). 200 due to limited processing speed
It was difficult to increase the scanning speed to 0 scanning / second or more.

The present invention is intended to solve the above problems, and an object thereof is to increase the scanning speed of a laser beam and the reading rate of bar codes.

[0006]

In order to achieve the above object, a bar code detecting apparatus of the present invention comprises a laser light source for emitting a laser beam, a condensing unit for condensing the laser beam and emitting a laser beam, Scanning means for scanning the laser beam, light receiving means for receiving the reflected light from the barcode of the scanning laser beam and converting it into an electric signal, and processing the electric signal output from the light receiving means to recognize the bar code. Signal processing means, the laser light source is composed of a plurality of semiconductor lasers, the condensing means is composed of a plurality of sets of condensing means, the light receiving means is composed of a plurality of light receiving means, the signal processing The means comprises a plurality of signal processing means.

[0007]

According to the above structure, by providing a plurality of laser beam generators and a plurality of sets of condensing means, it becomes possible to simultaneously scan a plurality of laser beams, and the response of the light receiving means is improved. Without this, the laser beam scanning speed of the bar code detecting device can be dramatically increased.

If the signal processing means is composed of a plurality of signal processing means, the processing speed can be increased and the scanning speed can be increased.

When the bar code detecting device has a plurality of laser beam generators and a plurality of signal processing means paired with each laser beam generator as described above, the scanning speed depends on the number of signal processing means. It can be raised proportionally.

[0010]

1 (a) and 1 (b) show an embodiment of a bar code detecting device of the present invention. FIG. 1 (a) is a plan view showing the structure of the device, and FIG. ) Is a front view.

A laser beam generator 3 comprising a visible semiconductor laser 1a which emits a laser beam having a wavelength of 670 nm and a set of aspherical lenses 2a having a focal length of 6.0 mm.
a emits the laser beam 4a. Laser beam 4
a passes through the hole in the center of the concave mirror 5a having a hole in the center and is scanned by the polygon mirror 6. The laser beam 4a scans the barcode 7, and the reflected light from the barcode 7 follows the same path as the emitted laser beam 4a, is reflected by the polygon mirror 6, and reaches the concave mirror 5a. Here, the reflected light is condensed on the PIN photodiode 8a by the concave mirror 5a. The PIN photodiode 8a converts the received light signal into an electric signal. A signal processing means 9a composed of a 16-bit 1-chip CPU processes the electric signal, decodes it, and detects a bar code. The result of the detection is sent to the communication means 10 composed of an 8-bit 1-chip CPU.

Similarly, a laser beam generator 3b composed of a visible semiconductor laser 1b which emits a laser beam having a wavelength of 670 nm and an aspherical lens 2b having a focal length of 6.0 mm emits a laser beam 4b. The laser beam 4b passes through the central hole of the concave mirror 5b having a central hole and is scanned by the polygon mirror 6. The laser beam 4b scans the barcode 7, and the reflected light from the barcode 7 follows the same path as the emitted laser beam 4b, is reflected by the polygon mirror 6, and reaches the concave mirror 5b. Here, the reflected light is reflected by the concave mirror 5b.
The light is focused on the PIN photodiode 8b. The PIN photodiode 8b converts the received light signal into an electric signal.
Signal processing means 9 composed of 16-bit 1-chip CPU
b processes and decodes the electric signal to detect the bar code. The result of the detection is sent to the communication means 10 composed of an 8-bit 1-chip CPU. The communication means 10 communicates the detected bar code to the host computer based on the results sent from the signal processing means 9a and the signal processing means 9b.

As described above, the He-Ne laser tube 11 and the three-lens spherical lens 12 have conventionally constituted the laser beam generator 13, but in the present invention, a visible semiconductor laser (wavelength of about 670 nm) 1a is used. , 1b and the aspherical lenses 2a, 2b having a single-lens structure, the laser beam generators 3a, 3b can be formed in a space of 1/5 of the conventional example, and a plurality of laser beams can be provided in one bar code detecting device. It has become possible to arrange the laser beam generators 3a and 3b. Also, the laser beam generators 3a and 3b are configured to be 1/10 of the conventional one in terms of cost.

According to the bar code detecting apparatus of the present invention, conventionally, the scanning speed is 2000 scans / second and the bar code reading rate when the truncation is less than 18 mm is 90%.
However, the scanning speed can be increased to 4000 scans / second, and the reading rate of the bar code with the truncation of 11 mm can be maintained at 90% or more.

[0015]

As is apparent from the above description, according to the bar code detecting apparatus of the present invention, the scanning speed of the laser beam for reading the bar code can be dramatically increased, and the bar code reading can be performed. The rate is increased, and the workability of reading barcodes can be greatly improved.

[Brief description of drawings]

FIG. 1A is a plan configuration diagram showing an embodiment of a bar code detecting device of the present invention. FIG. 1B is a front configuration diagram showing an embodiment of a bar code detecting device of the present invention.

FIG. 2A is a plan configuration diagram of a conventional barcode detection device. FIG. 2B is a front configuration diagram of a conventional barcode detection device.

[Explanation of symbols]

 1a, 1b Visible semiconductor laser (laser light source) 2a, 2b Aspherical lens (focusing means) 4a, 4b Laser beam 6 Polygon mirror (scanning means) 7 Bar code 8a, 8b PIN photodiode (light receiving means) 9a, 9b Signal Processing means

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Masahiro Dan, 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Seiichiro Tamai, 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (4)

[Claims] 1. A laser light source that emits laser light,
A light collecting means for collecting the laser light and emitting the laser beam, a scanning means for scanning the laser beam, and a light receiving means for receiving the reflected light from the bar code of the scanning laser beam and converting it into an electric signal. In a bar code detecting device provided with the laser light source, the laser light source is composed of a plurality of laser light sources, the light collecting means is composed of a plurality of sets of light collecting means, the light receiving means is composed of a plurality of light receiving means Detection device. 2. A laser light source that emits laser light,
Focusing means for focusing the laser light and emitting the laser beam, scanning means for scanning the laser beam, light receiving means for receiving the reflected light from the barcode of the scanning laser beam and converting it into an electric signal, A bar code detecting device comprising a signal processing means for recognizing a bar code by processing an electric signal output from a light receiving means, wherein the signal processing means comprises a plurality of signal processing means. 3. A laser light source that emits laser light,
Focusing means for focusing the laser light and emitting the laser beam, scanning means for scanning the laser beam, light receiving means for receiving the reflected light from the barcode of the scanning laser beam and converting it into an electric signal, In a bar code detecting device having a signal processing means for recognizing a bar code by processing an electric signal output from a light receiving means, the laser light source is composed of a plurality of laser light sources, and the condensing means is composed of a plurality of sets. A bar code detecting device comprising light collecting means, said light receiving means comprising a plurality of light receiving means, and said signal processing means comprising a plurality of signal processing means. 4. A laser light source that emits laser light,
Focusing means for focusing the laser light and emitting the laser beam, scanning means for scanning the laser beam, light receiving means for receiving the reflected light from the barcode of the scanning laser beam and converting it into an electric signal, A bar code detecting device comprising a signal processing means for recognizing a bar code by processing an electric signal output from a light receiving means, wherein a plurality of semiconductors for generating the laser light having a wavelength between 600 nm and 700 nm by the laser light source. A bar code detecting device comprising a laser, the condensing means comprising a plurality of sets of aspherical lenses, the light receiving means comprising a plurality of photodiodes, and the signal processing means comprising a plurality of CPUs.