JPH0736111A - Method for encoding bar code for microfilm - Google Patents

Abstract

PURPOSE:To make reading accuracy hardly lowered even when microfilm is scratched, or dust or dirt sticks on the microfilm and to execute accurate read by expressing information based on the length of a black code imprinted on the microfilm. CONSTITUTION:The black code 24 showing the start of a bar code 18A has length L3, and a white code 24a having the length L3 is provided next to the black code 24. The black code 26 next to the code 24a shows '0' and has length L4. The white code 26a having the length L4 is successively provided next to the code 26. Furthermore, the black code 28 shows '1' and has length L5, and the white code 28a having the length L5 is successively provided next to the code 28. By properly combining the black codes 26 and 28 in such a way, the fixed information is expressed, and the black code 30 and the white code 30a showing the stop of the bar code and having length L6 are provided last. The black codes 24, 26, 28, 30 and 32 are not affected by the scratch, or the sticking of the dust or the dirt because they are originally black even when they are scratched, or the dust or the dirt sticks to them. Even when the white codes 24a, 26a, 28a and 30a are scratched, or the dust or the dirt sticks to them, the codes are accurately read without being affected thereby at all.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for coding a bar code to be printed on a microfilm.

[0002]

2. Description of the Related Art In microfilm, a mark such as a search blip is imprinted, the blip is read by a microfilm reader and counted, and a target frame is searched by using this count value as a frame address. There is. For example, the address of the frame with the 100th blip from the beginning is set to 100.

When a plurality of document groups are imprinted, it is sometimes desired to change the address range for each group. For example, manuscripts in group A have addresses 100 to 2
00 for the B group, and 400 for the address.
This is a case where it is desired to set the range to 500. In such a case, conventionally, a mark for changing the address has been imprinted on each group by a bar code. For example, it is considered that a bar code (random batch code) indicating a number smaller than the first address of the group by one is imprinted immediately before the certain group.

On the other hand, for a frame for which shooting has failed, the same frame may be shot again after the failed frame. At this time, the blips will overlap.
In addition, a frame that failed to be shot may be shot at another address. In this way, to prevent duplication of addresses and to indicate the address at which the frame for which shooting failed was retaken,
It is considered to imprint a barcode (error repair code).

FIG. 5 is a plan view of a conventionally proposed microfilm on which a bar code of this type has been imprinted, and FIG. 6 is an explanatory view of the bar code encoding method.

In FIG. 5, reference numeral 10 is a roll-shaped negative microfilm, 12 is a frame in which a large number of frames are imprinted at regular intervals, and 14 is a blip as a search mark imprinted below each frame 12. is there. A blank area 16 in which the frame 12 is not photographed is provided in the microfilm 10, and a barcode 18 is printed below the blank area 16.

As shown in FIG. 6, the bar code 18 is composed of a black code and a white (transparent) code, and a black code 20 and a white code 22 separately represent information. For example, the lengths of these codes 20 and 22 are L ₁ and L ₂ , and L ₁
Codes 20a and 22a having a length of 0 are encoded as "0" regardless of black and white, and codes 20b and 22b having a length of L ₂ are encoded as indicating "1" regardless of black and white.

[0008]

[Problems of the Prior Art] Generally, in a microfilm, the film may be scratched, dusty, or soiled. If the scratches, dust, and dirt are attached to the white code 22 of the bar code 18, the white code 22 may be inaccurately read or unreadable.

The duplication of the microfilm is usually carried out by exposing the master film on the dupe film by using a duplicator. At this time, as the dupe film, an N → P system that normally prints a negative image of the master film as a positive image is used.

In this way, duplication
When the negative / positive is reversed, the black and white information read from the bar code must be reversed.
There was a problem.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is difficult to reduce the reading accuracy even if the microfilm is scratched, dusty, or dirty, and the bar for microfilm can be read accurately. A first object is to provide a code encoding method.

It is a second object of the present invention to provide a bar code encoding method in which the read information can be used as it is without being inverted even if the black and white of the image is inverted when the microfilm is reproduced. .

[0013]

According to the present invention, the first object is achieved by a method of encoding a bar code for a microfilm, characterized in that information is represented by the length of a black code projected on a roll-shaped microfilm. To be done.

The second object is achieved by the method for encoding a microfilm bar code according to claim 1, wherein a transparent blank portion having the same length as the black code is provided after the black code. In this case, the bar code may be imprinted separately on both edges of the film.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a plan view of a microfilm which is an embodiment of the present invention, FIG. 2 is a view for explaining the construction of its bar code, and FIG. 3 is a view showing a read signal of this bar code.

The bar code 18A printed on the microfilm 10A shown in FIG. 1 has a simplified structure shown in FIG. In FIG. 2A, 24 is a black code indicating the start of the bar code and has a length of L ₃ . Next to the black code 24, a white (transparent) code 24a having the same length L ₃
Is provided. The next black numeral 26 denotes an example "0", it is L ₄ length. Then, a white (transparent) code 26a having the same length L ₄ follows.

A black code 28 indicates "1" and has a length of L ₅ . Then, a white code 28a having the same length L ₅ follows. As described above, the black symbols 26 and 28 are appropriately combined to represent certain information, and finally, the black symbol 30 and the white symbol 30a having the length L ₆ indicating the stop are provided. 32 is this white code 30
A black code for indicating the end of a. As described above, the black symbols 24, 26, 28, 30 are always followed by the white symbols 24a, 26a, 28a, 30a having the same length.

With respect to the bar code 18A of the microfilm 10A, only the black symbols 24, 26, 28, 30, 32 are read by a microfilm reader (not shown), and the contents are judged from the respective lengths. It A microfilm reader suitable for reading the microfilm on which the bar code is recorded is described in Japanese Patent Laid-Open No. 4-3254, and the description thereof will be omitted. FIG. 3A shows this output signal.

Here, black symbols 24, 26, 28, 30, 3
No. 2 is not affected by scratches, dust, and dirt because it is originally black, and white symbols 24a, 26a, 28
Even if a, 30a are scratched, dusty, or smeared, they can be read accurately regardless of the fact.

Further, when this film 10A is used as a master film in black-and-white reversal for duplication, the barcode 18B at that time becomes as shown in FIG. 2B. That is, the white symbol 24a on the film 10A,
26a, 28a, 30a are black symbols 24A, 26A, 28A, 30A on this dupe film.

Therefore, when this dupe film is loaded into the microfilm reader, the black symbols 24A and 26
Read only A and 30A. The output signal is shown in FIG.
The result is as shown in FIG. Therefore, from the signal of FIG. 3B, the bar code 18
It becomes possible to determine the contents of B.

According to the present invention, since the white code having the same length is added next to the black code, the total length of the bar codes 18A and 18B becomes long and the blank area 16A on the film 10A becomes large (see FIG. 1).

FIG. 4 is a plan view of a microfilm 10B showing an embodiment for solving such a problem, in which the bar codes 18C and 18D are separately printed on the upper and lower edges of the film 10B. Film 10
Both of the barcodes 18C and 18D are read and stored in memory during the conveyance of B, and both are combined according to a predetermined algorithm to express predetermined information. By doing so, the blank area 16B can be reduced, and the film 10B can be effectively used.

[0024]

As described above, according to the first aspect of the present invention, since the bar code indicating the information with the length of the black code is imprinted on the microfilm on the roll, only the black code is read when reading the bar code. Just read it. Since the black code is less likely to be erroneously detected by scratches, dust, and dirt, the barcode reading accuracy is improved.

Next to each black code, white of the same length (transparent)
If the code is attached, the white code on the master film is imprinted as the black code on the dupe film when the image is reproduced negatively and positively and duplicated on the dupe film. Therefore, the same effect as that of claim 1 is obtained, and
There is no need to invert black and white when reading a barcode on a dupe film.

If the white code of the same length is added next to the black code, the total length of the bar code becomes long. However, if this bar code is divided and recorded at the upper and lower edges of the film, a blank area of the film is obtained. Is reduced, and the film can be effectively used (claim 3).

[Brief description of drawings]

FIG. 1 is a plan view of a microfilm showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram of the bar code configuration.

FIG. 3 is a diagram showing a bar code reading signal.

FIG. 4 is a plan view of a microfilm showing another embodiment.

FIG. 5 is a plan view of a conventional microfilm.

FIG. 6 is an explanatory diagram of the bar code configuration.

[Explanation of symbols]

 10, 10A, 10B Microfilm 18, 18A, 18B, 18C, 18D Bar code 24, 26, 28, 30, 32 Black code 24a, 26a, 28a, 30a White code

Claims (3)

[Claims] 1. A method of encoding a bar code for a microfilm, wherein information is represented by the length of a black code projected on a roll-shaped microfilm. 2. The method for encoding a microfilm barcode according to claim 1, wherein a transparent blank portion having the same length as the black code is provided next to the black code. 3. The method of encoding a microfilm bar code according to claim 2, wherein the black code is separately printed on both edges of the microfilm.