JPH0410089A - Method and device for identifying id code - Google Patents

Abstract

PURPOSE:To improve the performance of identification by extracting a dictionary data for ID identification from an input picture, registering the extracted dictionary data and reading an ID code by using the registered dictionary data. CONSTITUTION:Just after a character or a code as the object of identification is written into a product 1 or a member, the picture state of the ID code 2 is stored and the pattern of the entire code is set to a dictionary pattern. Otherwise, the feature amount of the written code is evaluated according to a certain fixed rule and only the feature amount is defined as the dictionary data. Then, the dictionary of the ID code 2 is prepared and stored corresponding to the issue information of the product and afterwards, the ID code 2 is identified based on this dictionary. In such a way, the dictionary data is formed not only for the unit of each character in the ID code 2 but the data is collected from the product itself while evaluating the feature amount such as the respective areas, sizes and peripheral lengths or the like of the picture pattern in a code area and a code part. Thus, printing dispersion in the case of writing the ID code and further, the product missing the printing can be prevented in advance from flowing out by the evaluation check of printing quality.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a dictionary pattern registration and recognition method for character identification in automatic ID number identification using pattern recognition, and storage of identification history based on identification results. The present invention relates to a method and apparatus for improving identification performance.

[Conventional technology]

Conventionally, automatic ID identification methods and devices have been disclosed in Japanese Patent Application Laid-Open No. 63
- As described in No. 308689, an area is set around a character in the input image, a check is made to see if there is a character within the area, the center coordinates of the character are detected, the inclination of the character is calculated, and then the character pattern is created. However, it does not describe a dictionary pattern generation method for matching character patterns. Also, in JP-A-1-96920, a detection method using infrared light is described as a wafer ID identification method, but a bar code is used as the ID code, and a dictionary pattern generation method for identification is described. is not mentioned. Further, although JP-A-1-213766 also describes an IDg identification device for semiconductor wafers, it is an image detection method using laser light, and there is no specific description of an ID code identification method.

[Problem to be solved by the invention]

All three of the above conventional techniques describe identification methods or detection methods and their devices, but all of them are based on I.
This information is provided only when the D code can be correctly identified.

Originally, in this type of identification, in order to prevent incorrect identification and providing incorrect information, the reading judgment conditions were set to be strict to actively prevent identification, and the system was designed to deal with this situation. No consideration was given to the specific method to do so, which caused problems in practical application.

An object of the present invention is to provide a dictionary pattern registration method for ID code identification, an ID code identification method using the same, and a method for dealing with identification when identification becomes impossible.

[Means to solve the problem]

In order to achieve the above purpose, in applications where the ID code of a product is automatically identified using pattern recognition technology etc. for manufacturing control, immediately after writing the characters or code to be identified on the product or component, an image of the ID code is created. Either the state is memorized and the entire code pattern becomes a dictionary pattern, or the features of the written code are evaluated according to certain rules and only the features are used as dictionary data to create an ID code that is combined with product issue information. A dictionary is created and stored, and ID codes are subsequently identified based on this dictionary.

Furthermore, when automatically identifying ID codes and managing production online, if the code to be identified does not satisfy the identification rules for some reason and becomes unidentifiable,
Instead of issuing a warning and waiting until some kind of assistance work is performed and stopping the progress, the input image information at that time, along with the context of the product at that time, lot information, date and time, and unidentifiable process, is recorded in the unrecognizable history. Store it as information. The history information is made available as a service as needed, allowing workers and managers to reproduce situations that they cannot recognize and assist them with correct information.

[Effect]

Immediately after writing the characters and codes to be identified on the product or component as the ID code of the product, input the image of the ID code, and not only create dictionary data for each character of the ID code but also create several characters and codes. In order to turn the entire code consisting of symbols into a dictionary, we created a facility configuration that can collect data from the actual object by evaluating the image pattern of the code area at that time and the features such as the area, size, and perimeter of the code part. By storing the information in the identification device and clarifying the correspondence between the information at the time of ID code issuance and the dictionary data, it is possible to absorb printing variations when writing the ID code, and also to check the evaluation of printing quality. Prevent the leakage of incorrect products.

By using the dictionary data or dictionary pattern generated in this way to identify the ID code of the printed product, the shape of the pattern and code type for each product can be compared with those of the individual product itself. , it can be identified without considering variations in printing or the code type for identification, and furthermore, it can be put to practical use with a simple identification method that reduces the ability to understand the code.

In addition, when applying an identification device in-line in a production line, if the code to be identified does not satisfy the identification conditions for some reason and becomes unidentifiable, the ID code of the products before and after that time , the function to store the input image at that time as history information of unidentifiable products, along with the lot information (which can be omitted if unknown), date and time, and the process of identification that became unidentifiable. The information is stored in an identification device with a medium.

With this configuration and function, instead of issuing an alarm and waiting unidentified until some kind of assistance work is performed and stopping progress, the next product can be identified and manufactured without stopping the flow of products. You can manage the progress of the line. The ID codes for products that could not be identified can be repaired at the end of a lot, at regular checks, or when a certain amount of unidentifiable products are stored, so that history information can be made available to workers and managers. To instantly restore a correct ID code without having to reproduce an unrecognizable situation, extract an unrecognized product from a production line, reproduce the phenomenon, or read the ID code from the actual product.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on FIGS. 1 to 11. FIG. 1 shows an ID code 2 written on a product 1, which is imaged by an optical system 3 including a sensor such as a TV camera, converted into an image signal 5, imported into an identification device 4, and then processed by a pattern recognition method. It is a diagram showing a configuration for automatically identifying an ID code, and shows a configuration when one or more optical systems are connected to one recognition device. Here, the TV monitor 6 is for displaying images input to the identification device and identification results. FIG. 2 is a diagram showing the internal configuration of the identification device 4. In the identification device 4, the image signal 5 of the ID code 2 output from the sensor part 3 is sent to the image input/output board 9.
An image processing board 1 that inputs image data as displayed on a monitor 6 and performs image processing such as pattern matching with a CPU board 10 in the identification device based on this image data.
2, the ID code 2 is identified from the manually generated image. These boards are connected to each other by a CPU data line 14 and an image data line 15 to operate, and these data lines also contain recognition results, a history of the recognition process, and a dictionary pattern for identification. A storage device (IC memory) for storing data etc.

(such as a disk) 7, a storage device control board 13 for controlling it, and a communication board 11 for communicating recognition results and recognition request commands with an external device via a communication line 8.

A method of identifying an ID code using an identification device having such a configuration and an application method using the same will be described with reference to FIGS. 3 and 4, with reference to semiconductor manufacturing process steps. FIG. 3 shows the relationship between the macro process flow of the semiconductor process and the identification device. At the same time as a wafer 17a is introduced into the semiconductor manufacturing process, an ID code printing device 180 prints characters on the wafer 17b. Print. Next, the printed wafer 17c is normally put into the first step of the manufacturing process, such as the oxidation/CVD device 18, but here, the printed wafer 17c is used as an ID. Code identification device 4a
An image of the ID code state is inputted by the optical system 3a. Then, based on the image state, the identification device 4a associates the product information from the manufacturing process management system 23 such as production progress management with the ID code image. Furthermore, the printing quality of the ID code is checked from the image with this association, and at the same time, the dictionary pattern data for identifying this twisted code during the manufacturing process is evaluated and registered in the storage device 7 shown in FIG. This dictionary pattern is then used to perform identification processing during the entire process. By doing this, it is possible to prevent products with misprinted ID codes from being sent to the production line, and at the same time, it is possible to register the dictionary pattern from the ID code of the product immediately after it has been written. Printing conditions, such as slight positional deviations, blurred characters, and combinations of characters, can be registered as characteristic dictionary for character identification, and what would normally be a disturbance element for identification can be registered as pattern information for identification. able to play an effective role. Therefore, it is only necessary to recognize a pattern in which the dictionary pattern and the product ID code are the same, and the method can be applied using a simple identification method. Therefore, as shown in FIG. 3, the identification device for each manufacturing process (apparatus) 18 to 22 can identify the ID code of the product by transmitting dictionary pattern information from the identification device 4a through the communication line 8b. I can do it.

At this time, the conditions such as magnification of each identification device 4b to 4f and optical system 3b to 3f must be the same as those of the identification device 4a and optical system 3a in which the dictionary pattern is registered, but condition coefficients can be set in advance. This is not the case, since the identification device can automatically convert the input image to match the conditions of the input image. Further, the identification results are collected in the process management system 23 through the communication lines 8a and 8c, and the information is sent to the equipment of each manufacturing process to perform manufacturing according to the ID code. Rather than centrally collecting and managing the identification results, it is of course possible to send the information to each device and have it managed. (Not shown.) Also, the third
In addition to providing and applying an identification device for each manufacturing process or manufacturing device as shown in the figure, printing quality and dictionary data registration immediately after printing an ID code with one identification device 4 as shown in FIG. Identification may also be performed. in this way,
The reason why it is possible to identify the code pattern immediately after writing the ID code as the master is because once the ID code itself is written, it is assumed to be unchangeable and no changes or additions are made during the process, and even if such a thing were to occur, This is because in some cases, it is natural that product history will be managed based on ID codes.

Next, a dictionary pattern registration method for ID code identification and an identification method will be explained based on FIGS. 5, 6, and 7. As shown in FIG. 5(a), after printing, the wafer 1
Figure 5(b) input from 7 (printing device not shown)
Based on the images 24a to 24C shown in FIG. 6, the meanings of dictionary numbers and ID codes are registered as dictionary data in which pattern data and feature quantities α1 to αn are associated. Pattern data 25a-2 at this time
5n may be the area of the circumscribed rectangle of the entire ID code, and there is no need to specifically limit its size, but it is necessary to standardize it to check whether it is appropriate as a dictionary pattern. Furthermore, as shown in FIG. 6, it is easier to manage the meaning of the ID code by using the same ID code, but this is not the only option. In addition, the feature values are used to organize the dictionary in conjunction with dictionary pattern searches and product classification, and narrow down the dictionary pattern candidates for identification purposes from a large number of dictionary patterns to a few, speeding up the identification process. We are making it possible to do so.

There is no need to limit this feature amount either, and a simple evaluation value such as the total area occupied by the character portion may be used. These feature amounts are stored in the storage device 7 shown in FIG. 2, so that they can be used in common with other identification devices.

Next, a method for recognizing ID code identification using the above-mentioned dictionary data will be explained with reference to FIG. As shown in FIG. 7(a), the input image is cut out into the entire code area as shown in FIG. 7(b). This area is extracted by detecting the circumscribed rectangle of the entire literature section of the ID code in the same way as the dictionary pattern registration method. Then, by matching with already registered dictionary pattern data, the most matching dictionary No., is detected, and the code meaning for the dictionary No. is read out to identify the ID code.

On the other hand, in the conventional dictionary pattern registration method shown in FIG. Input the image 27 shown in FIG. 9(b), and either register the character's font pattern, area perimeter, and other feature quantities as dictionary data for each character as shown in FIG. 9, or design the character shape in advance. In order to create data and perform identification processing, the data shown in Fig. 10 (a
), in each input image, each character is cut out from the ID code as shown in (b) of the same figure, and the cut out characters are matched with the already registered dictionary pattern, character by character. This method has two disadvantages: each character is an identification unit, so a large number of types of dictionary data are required;
As shown in Figure 0 (a), complex characters must be precisely extracted from images (2) and (3) in which the characters are arranged irregularly. Furthermore, if the characters are blurred as in input image (4), it becomes impossible to identify them.

As described above, compared to the conventional method, the ID code identification method of the present invention has the effect of simplifying dictionary pattern registration and character extraction, and at the same time improving the identification rate. This is due to reducing the number of dictionary pattern types and increasing the number of data elements contained in the dictionary patterns.

However, even with these identification methods, the ID code portion may be damaged while the product is on the production line, making it impossible to identify the product. In such a case, the identification history data stored at that time in the storage device 7 shown in FIG. 2 is shown in the following (1) to (6).

(1) Serial number (2) Date and time (3) Lot information, etc. (4) Input image data (5) Identification judgment evaluation value (6) ID code of 1 or N previous product The information when identification is not possible is as follows: The reason why the date and time such as month, day, hour, minute, etc., the type or lot information at that time, and the file name of the human image that could not be distinguished from the information serial number in the format shown in Figure 11 The identification evaluation value for analysis, the ID code of the previous product, the temporary code, and the repair history of the temporary code are stored. Basically, this information may be operated by being stored in each recognition device shown in FIGS. 3 and 4, or the information may be sent and managed by a device that manages the entire system. By doing this, you can register the history of unidentifiable products and
The information is sent to the production management system 23 shown in FIG.
Therefore, by attaching a temporary ID code corresponding to the serial number shown in FIG. 11 to unidentifiable products, manufacturing can proceed without stopping the flow of products. Each identification device or production management system is configured to be able to notify the production line manager of the situation in which identification is not possible in the format shown in FIG. Then, the management can call up the unidentifiable history, image status, etc. and restore it to an official ID code, thereby restoring the manufacturing management to normal. It goes without saying that this repair work can be performed either by each identification device or by having a configuration in which the history data of the identification devices can be called up in the place that manages the entire system.

Here, the date and time in FIG. 11 can be realized by providing a real-time clock that can be read from the CPU of the identification device, and can also be managed in seconds if necessary. Also,
Type/lot information varies depending on the type of operation of the system, but is used only when the information can be obtained in some form from outside the identification device. This allows unidentifiable aggregation to be performed on a product/lot basis, making it possible to check for unstable factors in the manufacturing process at the ID code reading stage, and to check the printing status of the ID code and the identification device. You can also give feedback on your shortcomings. Moreover, the input image can be easily realized by providing a storage device. The identification evaluation value indicates at what point in the recognition process of ■D identification it became impossible to identify, and this information allows the cause of the inability to be identified to be analyzed. In addition, the ID code of the previous product indicates the relationship between the products when identification is not possible, and the ID code of the next product when identification is not possible is added to this information and stored in order to maintain regularity in the flow of products. Automatic repair is also possible if available. The temporary code is a code that follows the operating rules of the system, and since the product type information is known in advance, a special code is attached to the product type information to make it a serial number and the number of characters is matched. Then, the system can be operated by recording the date and time when the repair work was performed as a repair history.

〔Effect of the invention〕

As explained above, the present invention basically identifies ID codes by providing hardware for an identification processing function, a mechanism for storing dictionary patterns, image data, and identification history data, and a communication mechanism in an identification device. It is possible to bring the production line online. In addition, the recognition rate of ID code identification has been improved, and when identification becomes impossible for some reason, instead of issuing an alarm and waiting until assistance work is performed without stopping progress, the next step is to It is possible to identify products and manage the progress of the production line without stopping the flow of products. The ID codes for products that could not be identified can be repaired at the end of a lot, at regular checks, or when a certain amount of unidentifiable products are stored, so that history information can be made available to workers and managers. To instantly restore a correct ID code without having to reproduce an unrecognizable situation, extract an unrecognized product from a production line, reproduce the phenomenon, or read the ID code from the actual product.

[Brief explanation of the drawing]

FIG. 1 is an external configuration diagram of an ID code identification device of the present invention. FIG. 2 is a hardware configuration diagram of the identification device. 3 and 4 are schematic diagrams of the identification system in the production line. 5 and 6 are schematic diagrams of the dictionary pattern registration method of the present invention. FIG. 7 is a schematic diagram of the ID code identification method of the present invention. FIGS. 8 and 9 are schematic diagrams of a conventional dictionary pattern registration method. Figure 10 shows the conventional ID
FIG. 3 is a schematic diagram of a code identification method. FIG. 11 is a diagram showing the format of identification history data to be stored when the ID code cannot be identified. 1... Product to be identified, 2... ID code, 3...
Optical system including TV camera, 4...Identification device, 7...
-Storage device, 8...communication line. 1st item 4-Boss/3 Precision 1st

Claims (1)

[Claims] 1. In an ID code identification method for identifying an ID code and managing a manufacturing process based on the ID code, the ID code is assigned after an ID code is assigned to a product or a semi-finished product as an object of manufacturing and assembly. input an image of An ID code identification method characterized by reading and identifying a code. 2. After assigning the ID code to the object, the ID code pattern is used as dictionary pattern data, and the ID code is assigned a meaning to the dictionary pattern data and registered in the dictionary, and the manufacturing process of the object is controlled. By detecting the most matching dictionary pattern data from among the registered dictionary pattern data in the identification unit, the ID code can be identified without analyzing the individual character patterns, code system, and meaning of the ID code. An ID code identification method characterized by: 3. In the ID code identification method according to claim 1 or 2, when the ID code cannot be identified in the identification section of the manufacturing process, the input image, date and time, or An ID code identification method characterized by storing non-identifiable determination information as historical information and reproducing a situation when identification was impossible. 4. In an ID code identification device that identifies an ID code and manages manufacturing processes based on the ID code, means for inputting an image of an ID code assigned to a product or a semi-finished product as an object of manufacturing and assembly; ID from the input image
The method is comprised of means for extracting dictionary data for identification, means for registering the extracted dictionary data, and identification means for reading the ID code of the product or semi-finished product in the manufacturing process using the registered dictionary data. Characteristic ID code identification device. 5. The ID code identification device according to claim 4, wherein means for registering the dictionary data is provided in the identification means. 6. The dictionary data can be sent from the means for registering the dictionary data via the communication means to the identification means corresponding to a plurality of manufacturing processes, and the identification devices can use the dictionary data in common. The ID code identification device according to claim 4.