JPH0736112A - Method for encoding bar code for microfilm - Google Patents

Abstract

PURPOSE:To prevent reading accuracy from being lowered even when microfilm is scratched, or dust or dirt sticks on the microfilm and to execute accurate read by orderly providing black codes showing information different from each other at both edge parts of the microfilm so that they are shifted each other in a film feeding direction. 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 next black code 26 shows '0' and has length L4. The white code 26a is successively provided next to the code 26. After two cosecutive sets of black code 26 and white code 26a just behind the code 26, the very short black code 28 showing the end is provided. Meanwhile, the bar code 18B has the black code 30 showing '1' and the white code 30a succeeding to the code 30 and having the same length as the code 30 somewhat behind the front edge of the code 28. After two sets of black and white codes 30 and 30a showing '1', the black code 32 showing the end is provided. Even when the black codes 24 to 40 are scratched, or the dust or the dirt sticks to them, the codes are accurately read without being affected thereby because they are originally black.

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.

Further, in the conventional bar code shown in FIG. 5, "0" and "1" are distinguished depending on whether the code length is L ₁ or L _2, so that it is necessary to accurately detect the film feed amount. is there. Therefore, there is a problem that an expensive device such as a rotary encoder is required.

Further, the duplication of the microfilm is usually carried out by using a duplicator and exposing the master film on the dupe film. 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 also a problem.

[0012]

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, so that accurate reading can be performed and the cost is high. A first object of the present invention is to provide a method for encoding a microfilm barcode that does not require a rotary encoder.

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. .

[0014]

According to the present invention, a first object of the present invention is to provide black marks, which indicate different information, on both edges of a roll-shaped microfilm in order in the film feeding direction so as to be offset from each other. This is achieved by the method of encoding a microfilm barcode.

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. The bar code may indicate binary information of "0" and "1", and "0" and "1" may be recorded on both edges by black code of the same length.

[0016]

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 microfilm 10A shown in FIG.
A bar code 18 is provided below and above the blank area 16A.
A and 18B are imprinted, and these have a simplified structure shown in FIG. Hereinafter, the barcode 18A will be referred to as an A channel (Ach), and the barcode 18B will also be referred to as a B channel (Bch). In FIG. 2A, 24 is a black code indicating the start of the bar code and has a length of L ₃
Is. Next to the black code 24, a white (transparent) code 24a having the same length L ₃ is provided.

The next black code 26 indicates, for example, "0" and has a length of L ₄ . Then, a white (transparent) code 26a having the same length L ₄ follows. After two sets of the black code 26 indicating “0” and the white code 26a immediately following the black code 26, the white code 2
A very short black code 28 is provided to indicate the end of 6a.

On the other hand, the Bch bar code 18B has a black code 30 indicating "1" slightly behind the front edge (left edge) of the black code 28 and a white code 30a of the same length following the black code 30. The lengths of the black / white symbols 30 and 30a are the same as the length L ₄ of the black symbol 26 indicating "0". Bch is provided with a black code 32 indicating the end of the last white code 30a after two sets of black / white codes 30 and 30a indicating "1" are continued.

Slightly behind the leading edge of the black code 32,
The black code 26 indicating "0" and the white code 26a immediately after that are entered again in Ach, and the end of the white code 26a is the black code 34.
Is set by. Bch is provided with a black code 30 and a white code 30a indicating "1" behind the front edge of the black code 34,
The end of the white code 30a is set by the black code 36. A black code 38 indicating a stop and a white code 38a are provided on the Ach after the leading edge of the black code 36.
The end of 8a is set by the black symbol 40.

Binary information "001101" is recorded by the above-mentioned bar codes 18A and 18B. The length of the black code 38 indicating the stop may be the same as the length L ₃ of the start black code 24, or may be another length L ₅ . In this way, the black symbols 24, 26, 30, 38 are always followed by the white symbols 24a, 26a, 30a, 38 of the same length.
a is provided.

This microfilm 10A is sent to the left in FIGS. 1 and 2 in a microfilm reader (not shown), and black symbols 24, 26, 28, 30, 32 ... 40.
Is read and the content is determined from the respective lengths. FIG. 3A shows this output signal. A microfilm reader to which this film 10A can be applied is disclosed in Japanese Patent Laid-Open No.
Since it is described in Japanese Patent No. 3254, etc., the description thereof will be omitted.

Black marks 24 to 40 are not affected by scratches, dust, and dirt because they are originally black, and white marks 24a, 26a, 30a, and 38a have scratches, dust, and dirt. Even if it is, it can be accurately read without any relation.

The information of "0" recorded on the Ach bar code 18A has the same length L ₄ , so that the lengths L ₃ and L _{5 of the} start and stop black symbols 24 and 38 are eventually.
And the length L ₆ of the black symbols 28, 34, 40 indicating the end of the white symbol can be clearly identified. That is, the length L ₄ may be set so that it can be distinguished from the extremely long L ₃ and L ₅ and the extremely short L _6, and it is not necessary to increase the length detection accuracy.

Therefore, the feed amount of the film 10A can be obtained by using the output of the rotation detector of the servo motor for stepping the film or the stepping motor itself. That is, an expensive rotary encoder becomes unnecessary.

When this film 10A is used as a master film and is reproduced by reversing it in black and white on the dupe film 10B, the barcodes 18C and 18D at that time are shown in FIG.
As shown in. That is, Ac on film 10A
h and Bch become Cch (barcode 18C) and Dch (barcode 18D), and white code 2 on film 10A
4a, 26a, 30a, 38a are black symbols 24A, 26A, 30A, 38A on this dupe film.

Therefore, when the dupe film 10B is loaded in the microfilm reader and sent in the left direction in the drawing, only the black symbols 24A, 26A, 30A and 38A are read.
The output signal is as shown in FIG. 3B, which is the black-and-white inverted version of FIG. 3A. Therefore, the contents of the barcodes 18C and 18D can be discriminated from the signal of FIG. 3 (B).

In this embodiment, Ach (bar code 18
A) shows a length L ₄ of a black code 26 indicating “0”, and Bch
Although the length L ₄ of the black code 30 in which the (bar code 18B) indicates “1” is made the same, it is not always necessary to make it the same. In this embodiment, as shown in FIG. 2A, when the black code to be read changes between Ach and Bch, black codes 28, 32, 34 and 36 indicating the end of the white code are provided for identification. I am trying to do it. However, these can be omitted by adjusting the timings of A and Bch.

FIG. 4 is a diagram showing an example of this case. In this microfilm 10C, the front edge of the black code 30 of Bch is positioned at the timing t ₀ when the white code 26a of Ach moves to Bch. On the contrary, the timing t _{1 at} the end of the white code 30a of Bch is the black code 26 of Ach.
The front edge of the is located. As described above, the end of the white code may be determined by using the leading edge of the black code of the different channel.

Further, in the above description, since the bar code records binary information, for example, "0" and "1" are assigned to each channel.
It suffices to record only the black code of the length indicating. However, in the present invention, black codes having different lengths indicating two or more pieces of information may be recorded in each channel.

[0031]

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 roll-shaped microfilm, only the black code is read when the bar code is read. 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.

The bar codes are provided on both edges of the film, and the black codes indicating different information are sequentially provided by shifting in the film feeding direction. There are fewer types of code length. Therefore, the detection accuracy of the film feed amount can be reduced, and it is not necessary to use an expensive rotary encoder or the like.

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.

The bar code here records binary information, and the bar codes at both edges are "0" and "1", respectively.
It is possible to make the lengths of the black symbols indicating and the same (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, 24A, 26, 26A, 30, 30A, 38, 3
8A Black code 24a, 26a, 30a, 28a White code

Claims (3)

[Claims] 1. A method for encoding a microfilm barcode, wherein black code indicating different information is provided at both edges of a roll-shaped microfilm so as to be offset from each other in the film feed direction in order. 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. A bar code for recording binary information of "0" and "1", wherein "0" and "1" are respectively provided at the edges of the microfilm by black symbols of the same length. The method for encoding a microfilm barcode according to claim 1 or 2, which is recorded.