JP2003302354A - Appearance inspection method and appearance inspection device for electronic circuit parts, and method for manufacturing electronic circuit parts - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an appearance inspection method for electronic circuit parts capable of enhancing processing accuracy and processing speed when an appearance inspection is carried out on electronic circuit parts by using color image processing, and an appearance inspection device used for the same. <P>SOLUTION: Color information on an inspection surface comprising three coordinate components of a three dimensional color space coordinate system in each position within the inspection surface is produced by an image processing device 11 on the basis of detection output signals indicating color image information in each position within the inspection surface outputted from a color light receiving section 2. A difference of each coordinate component between color data on the inspection surface and first acceptable quality reference color information corresponding to the coordinate component of color data on the inspection surface of the first acceptable quality color information which is set in advance is obtained, and a first image data comprising a result thus obtained is formed. Further, a rejection candidate region on the inspection surface is selected by a first stage image processing by use of the first image data. Then, a second stage image processing is executed only on the selected candidate regions so as to specify a rejection region on the inspection surface. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an appearance inspection method and appearance inspection apparatus for electronic circuit parts, and a method for manufacturing electronic circuit parts, and more particularly, to an electronic device suitable for high precision and high speed appearance inspection. The present invention relates to a visual inspection method for a circuit component, a visual inspection apparatus used for the same, and a method for manufacturing an electronic circuit component having a step of performing a visual inspection by the visual inspection method.

[0002]

2. Description of the Related Art In recent years, personal computers (PCs)
Not to mention the dramatic progress of computers such as workstations and workstations (WS), but also with the progress of image input / output devices such as cameras and scanners and image recording devices such as CDs and MOs Processing technologies such as processing accuracy have made remarkable progress. In such a situation,
Conventionally, the visual inspection of electronic circuit components such as package substrates and semiconductor components, which has hitherto relied on visual inspection, is about to undergo a technology shift to automation using image processing. It should be noted that the electronic circuit components in the present specification conceptually include well-known package substrates such as ceramic package substrates and plastic package substrates, and well-known electronic components including semiconductor components such as LSI and IC.

As the image processing method used for the appearance inspection, various methods such as a monochrome binary processing method by monochrome processing and a color image processing method have been studied. Further, in the appearance inspection using the color image processing, it is possible to enhance the ability to identify a subtle color difference in appearance as compared with the case where the black and white binarization processing is used. For this reason, it has been recognized that the color image processing method is a particularly useful method in the visual inspection of electronic circuit parts in which subtle color differences due to the constituent raw materials are likely to occur on the surface.

[0004]

When the appearance inspection of electronic circuit parts is performed by using the method based on the above-mentioned color image processing, generally, the non-defective product reference value which is the quality judgment is the judgment reference value visually obtained. It is set based on. Therefore, the image data used for the color image processing has a hue H, a saturation S, and a lightness I, which are close to human color perception, as coordinate components.
It is effective that it corresponds to the SI coordinate system. However, normally, in a color light receiving unit such as a camera or a scanner used for color imaging, a detection output signal when outputting an input signal of a captured color image does not correspond to the HSI coordinate system. for that reason,
In order to obtain image data corresponding to the HSI coordinate system, it is necessary to coordinate-convert the output value based on the detection output signal from the color light receiving unit. The processing time required for this coordinate conversion depends on the amount of information of the color image to be captured, but cannot be neglected for a large number of products such as electronic circuit parts that must be processed sequentially.

Therefore, it is conceivable that the image data used for the color image processing corresponds to the same three-dimensional color space coordinate system as the signal of the detection output from the color light receiving section. Examples of the three-dimensional color space coordinate system include an RGB coordinate system having coordinate components of red R, green G, and blue B, which are the three primary colors of light. The color image processing using the image data corresponding to such a three-dimensional color space coordinate system can shorten the processing time as compared with the color image processing using the image data corresponding to the HSI coordinate system. However, each R, G, and R of the image data corresponding to the RGB coordinate system
The B-coordinate component includes color information that humans cannot intuitively perceive, in addition to the side of colors that humans intuitively perceive, such as red, green, and blue. Therefore, H, which is close to human color perception
Compared with the case where color image processing is performed using image data corresponding to the SI coordinate system, it is difficult to set a non-defective product reference value required for image processing, and there is a problem that processing accuracy is reduced due to that. To be done.

The present invention has been made in consideration of the above problems. That is, the present invention provides a visual inspection method for electronic circuit parts, which can increase both the processing accuracy and the processing speed when performing visual inspection using color image processing, a visual inspection apparatus used for the same, and the visual inspection. An object of the present invention is to provide a method for manufacturing an electronic circuit component including a step of performing a visual inspection by the method.

[0007]

Means for Solving the Problems and Actions / Effects In order to solve the above problems, an appearance inspection method for electronic circuit parts according to the present invention is directed to an inspection light from an inspection surface of the electronic circuit parts at a color light receiving section. Light is received, and inspection surface color information composed of three coordinate components of the three-dimensional color space coordinate system at each position in the inspection surface is generated based on the detection output of the color light receiving unit, and at least one of the inspection surface color information is generated. Selecting a defective candidate area based on the difference between the inspection surface color data representing the coordinate component and the preset first non-defective product reference color information and the first non-defective product reference color data representing the coordinate component corresponding to the inspection surface color data, It is characterized in that a defective area on the inspection surface is specified by performing a defect determination process based on the selection result.

The above-described appearance inspection method for electronic circuit parts of the present invention is carried out by performing two-step image processing on the color image of the appearance of the inspection surface of the electronic circuit parts, which is the object of the appearance inspection. It is a thing. Therefore, the image processing in the first stage is to select a defect candidate area on the inspection surface. In selecting the defect candidate area, first, a color image of the appearance of the inspection surface is obtained by receiving inspection light from the inspection surface with a color light receiving unit, and the color image is input from the color light receiving unit. The detection output for the signal is output. Then, based on the detection output, the inspection surface color information including the three coordinate components of the three-dimensional color space coordinate system at each position on the inspection surface is generated. The inspection surface color information corresponds to three independent coordinate components of the three-dimensional color space coordinate system at each position on the inspection surface, that is, at each pixel position that partitions the color image of the appearance of the inspection surface. It is composed of three color space coordinate values. As described above, the inspection surface color information includes the position information of each position on the inspection surface and the color image information at each position.

After the inspection surface color information is generated, inspection surface color data representing at least one coordinate component of the inspection surface color information is prepared. In addition, a first non-defective item reference value is set in advance for each coordinate component of the color image information at each position on the inspecting surface that constitutes the inspecting surface color information, and a preset value consisting of these first non-defective item reference values is set. Of the thus obtained first non-defective item reference color information, first non-defective item reference color data representing a coordinate component corresponding to the inspection surface color data is prepared. Then, the difference in each coordinate component between the inspection surface color data and the first non-defective item reference color data prepared in this way is obtained by the calculation processing by the difference processing, and the first image data composed of the processing result is created. Further, as image processing using this first image data, those that exceed the set threshold value are extracted from the first image data. A set of each position on the inspection surface corresponding to the data extracted here is set as a defect candidate area on the inspection surface. By such image processing, a defect candidate area on the inspection surface is selected. The first image data used for the image processing in the first stage uses the same three-dimensional color space coordinate system as the detection output signal output from the color light receiving unit. As a result, in the process of creating the first image data, it is possible to shorten the processing time in the image processing without requiring the step of coordinate conversion.

After the defect candidate areas on the inspection surface are selected by the image processing on the first step as described above, only the second candidate step is selected for the selected defect candidate areas based on the selection result. The defect determination processing that is the image processing of is performed. By further narrowing down the defective areas on the inspection surface in the defect determination processing, the accuracy of specifying the defective areas can be improved. In this defect determination process, the image processing is performed only on the selected defect candidate area, so that the processing time can be shortened. By performing the two-step image processing as described above,
INDUSTRIAL APPLICABILITY The electronic circuit component appearance inspection method of the present invention can increase the processing accuracy and processing speed in the appearance inspection. Further, the second-stage image processing in the defect determination processing is the same as the first-stage image processing in the selection of the defect candidate area, the processing using the image data created by the difference processing, or the pattern matching method. It can be performed by the processing by.

Then, in the defect candidate area in the appearance inspection method for electronic circuit parts according to the present invention, a preliminary defect candidate area is extracted based on a difference between the inspection surface color data and the first non-defective item reference color data, and the preliminary defect candidate area is extracted. It is characterized by being selected by performing a defect candidate determination process based on the extraction result.

As described above, in the defective candidate area, the difference between the inspection surface color data and the first non-defective item reference color data is obtained by the difference processing, and the image processing using the first image data which is the processing result is obtained. Selected. This image processing is a processing of extracting the first image data that exceeds the set threshold value, but the set threshold value naturally influences the extracted data. This means that the defect candidate area selected by the set threshold is
For example, it means that various regions can be taken, such as corresponding to all the regions on the inspection surface or corresponding to a region smaller than the defective region to be specified. Further, when these various areas are used as preliminary failure candidate areas, the first image data is regarded as a form in which the preliminary failure candidate areas are extracted. Therefore, a threshold value set for selecting a defect candidate region from this preliminary defect candidate region in the defect candidate determination process, which is an image process, is at least acceptable as a good product at each position on the inspection surface. It should be within the range of numerical values. By setting the threshold value in this way, the selected defect candidate area can include at least the defect area on the inspection surface. On the other hand, if the threshold value set here is set to a value that is too small as compared with the numerical range that is acceptable as a non-defective product, then it is possible that all areas within the inspection surface will fall under the defect candidate area. .
Therefore, taking this into account, the types of electronic circuit parts,
In consideration of the acceptable range of non-defective products obtained at each position on the inspection surface, the lower limit value is appropriately set even when the threshold value is set to be within the numerical range of acceptable non-defective products.

As described above, in the defect candidate determination processing corresponding to the first-stage image processing, the first image data, which is the processing result obtained by the difference processing of the difference between the inspection surface color data and the first non-defective item reference color data, is used. The defective candidate area is selected by using this. Therefore, the inspection surface color data is set to represent the three coordinate components of the inspection surface color information, and the first non-defective item reference color data is set to correspond to each of the three coordinate components of the inspection surface color data. Then, the difference of each of the three coordinate components of the inspection surface color data and the first non-defective item reference color data is obtained by the difference processing, and the processing result is used as the first image data. By performing the defect candidate determination process on the three coordinate components using such first image data,
It is possible to improve the selection accuracy of the defect candidate area to be selected and further improve the processing accuracy in the appearance inspection.

Next, the defective area in the appearance inspection method for electronic circuit parts of the present invention is specified by using a three-dimensional color space coordinate system different from the three-dimensional color space coordinate system used for the inspection surface color information. It is characterized by doing.

As described above, the defective area is specified by performing the defect determination processing which is the second-stage image processing only on the defective candidate area selected in the first-stage image processing. In this defect determination processing, it is desired to accurately identify the defective area. Therefore, the second image data used for the defect determination processing is used for the three-dimensional color space coordinate system used for the inspection surface color information, that is, the first image data used for selecting the defect candidate area. It is different from the existing three-dimensional color space coordinate system. By performing the defect determination processing using such second image data, the number of 3 which is set in advance for selecting the defect candidate region is set.
With the first non-defective product allowable value corresponding to each coordinate component of the three-dimensional color space coordinate system, the defective area can be determined again using a different three-dimensional color space coordinate system. as a result,
It is possible to improve the accuracy of specifying the defective area specified in the defect determination processing.

Further, as a method for increasing the processing speed in the defect determination process, the second image data used in the defect determination process represents three color space coordinate values corresponding to each of the three coordinate components in the inspection surface color information. The data shall be based on the data created by coordinate transformation. By performing the defect determination process using such second image data, the processing time can be shortened. Further, the defect determination processing is performed only on the defect candidate area. Therefore, only the data corresponding to the area need be coordinate-converted, and the time required for the coordinate conversion can be significantly shortened as compared with the conventional method.

Further, in order to improve the accuracy of narrowing down defective areas in the defective judgment processing, the defective judgment processing is performed by using the same method as the image processing in the above-mentioned defective candidate area selection. That is, first, defective area specific color information including three coordinate components of the three-dimensional color space coordinate system at each position of the defective candidate area is generated. The defective area specifying color information is composed of positional information of each position of the defective candidate area and three color space coordinate values corresponding to three independent coordinate components of the three-dimensional color space coordinate system at each position. It includes color image information. Also,
This defective area specific color information is different from the inspection surface color information 3
The data corresponding to the defective candidate area among the data representing the three color space coordinate values corresponding to each of the three coordinate components in the inspection surface color information can be generated by coordinate conversion. . Next, defective area specifying color data representing at least one coordinate component of the defective area specifying color information is prepared. Further, a second non-defective item reference value is set in advance for each coordinate component of the color image information at each position of the defect candidate region forming the defective region specifying color information, and the second non-defective item reference value is set. Of the preset second non-defective item reference color information, the second non-defective item reference color data representing the coordinate component corresponding to the defective area specifying color data is prepared. Then, the difference in each coordinate component between the defective area specific color data and the second non-defective item reference color data prepared in this way is obtained by the calculation processing by the difference processing, and the second image data composed of the processing result is created. To do. Further, as defect determination processing that is image processing using this second image data, data that exceeds a set threshold value is extracted from the second image data. A set of each position on the inspection surface corresponding to the data extracted here is defined as a defective area on the inspection surface. By specifying the defective region on the inspection surface by such a defect determination process, the specifying accuracy can be improved.

Next, the above-mentioned defective area specifying color data is assumed to represent the three coordinate components of the defective area specifying color information, and the second non-defective item reference color data is set to each of the three coordinate components of the defective area specifying color data. It corresponds to. Then, the difference between the three coordinate components of each of the defective area specifying color data and the second non-defective item reference color data is obtained by the difference processing, and the processing result is used as the second image data. By performing the defect determination processing on the three coordinate components using such second image data, it is possible to further improve the identification accuracy of the identified defective area and further improve the processing accuracy in the visual inspection. You can

The above-described defect determination processing for obtaining the difference between the defective area specifying color data and the second non-defective item reference color data by difference processing and for specifying the defective area using the second image data resulting from the processing is The process of extracting the second image data that exceeds the set threshold value is naturally influenced by the set threshold value. This depends on the threshold set
It means that the specified defective area can take various areas such as corresponding to all areas of the defect candidate areas. Further, when these various areas are set as preliminary defective areas, the second image data is regarded as a form in which the preliminary defective areas are extracted. Therefore, the threshold value set for specifying the defective area in the defect determination processing from the preliminary defective area is set to be within a numerical range that is acceptable as a non-defective product at each position on the inspection surface. By setting the threshold value in this way, it becomes possible to further improve the accuracy of specifying the defective area to be specified.

So far, the method for increasing the processing accuracy and processing speed in the appearance inspection method for electronic circuit parts of the present invention has been described. A feature of the present invention is that the color image processing in the visual inspection is performed in two stages. In particular, the image processing in the first step and the second step is performed using image data having different three-dimensional color space coordinate systems. In such an appearance inspection method, the three-dimensional color space coordinate system of the first image data used in the first-stage image processing for selecting the defect candidate area, that is, the three-dimensional color space coordinates used for the inspection surface color information. It is particularly effective that the system is composed of RGB (red, green, blue) coordinate system. This is because a CCD camera is often used as a color light-receiving unit for color-capturing the appearance, and the detection output signal corresponds to the RGB coordinate system. Next, as the image data used for the defect determination processing, which is the second-stage image processing for specifying the defective area, it is particularly effective to use an HSI (hue, saturation, lightness) coordinate system. This is because it is necessary to set the non-defective item reference value of the electronic circuit component based on the determination standard obtained by visual observation, and the HSI coordinate system is made to be close to human color perception.

The defect determination process, which is the second-stage image process, is performed only on the defect candidate area selected in the first-stage image process. Therefore, when the data representing the three color space coordinate values respectively corresponding to the three coordinate components of the inspection surface color information in the RGB coordinate system is converted into the HSI coordinate system, only the data corresponding to the defect candidate area is used. Good. As a result, it is possible to significantly reduce the time compared with the time conventionally required for coordinate conversion to the HSI coordinate system.

Of course, the three-dimensional color space coordinate system used in each of the first-step image processing for selecting a defective candidate area and the second-step image processing for specifying a defective area is not limited to the above. Absent. For example, the image processing in selecting the defect candidate area is performed using the image data of the RGB coordinate system, and the image processing in specifying the defect area is R
It is also possible to adopt a pattern matching method using a GB coordinate system. Further, the image processing in selecting the defect candidate area is performed using the image data corresponding to one or two coordinate components of the RGB coordinate system, and the image processing in specifying the defective area corresponds to the three coordinate components of the RGB coordinate system. It is also possible to use the image data to be processed. Further, the RGB coordinate system and the HSI coordinate system are each made up of three independent coordinate components, but image processing is performed using image data made up of four or more coordinate components including coordinate components dependent on the coordinate components. It is also possible.

As described above, the three-dimensional color space coordinate system forming the image data used in the image processing is appropriately selected in consideration of the processing accuracy or processing time required in the appearance inspection processing. is there. First, a known three-dimensional color space coordinate system that constitutes the image data used in the image processing method or image processing in the present invention can be applied.

Next, a visual inspection apparatus for performing the above-described visual inspection method for electronic circuit parts will be described. Therefore, the appearance inspection device for an electronic circuit component according to the present invention includes a color light receiving unit that images the inspection surface of the electronic circuit component, and a three-dimensional image at each position on the inspection surface based on the detection output of the color light receiving unit. Inspection surface information generating means for generating inspection surface color information composed of three coordinate components of the color space coordinate system, inspection surface color data representing at least one coordinate component of the inspection surface color information, and a preset first non-defective reference color Defect candidate area selecting means for selecting a defect candidate area based on the difference from the first non-defective item reference color data representing the coordinate component corresponding to the inspection surface color data, and image processing is further performed only on this defect candidate area. Accordingly, a defective area specifying unit for specifying a defective area on the inspection surface is provided.

First, a color image of the inspection surface of the electronic circuit component is picked up by the color light receiving portion, and an input signal of the color image is detected at each pixel corresponding to each position on the inspection surface. The color light-receiving unit outputs a detection output signal corresponding to each of the three coordinate components of the three-dimensional color space coordinate system representing the color image in the pixel. next,
On the basis of the output analog signal of the detection output, inspection surface color information composed of three color space coordinate values corresponding to three coordinate components of the three-dimensional color space coordinate system at each position on the inspection surface is generated as a digital signal. The inspection surface information generating means can be provided in a computer such as a personal computer (PC). Then, inspection surface color data that represents at least one coordinate component of the inspection surface color information, and first non-defective product reference data that represents the coordinate component corresponding to the inspection surface color data in the preset first non-defective product reference color information. The difference of each coordinate component of is obtained by the arithmetic processing by the difference processing, the first image data consisting of the processing result is created, and the ones exceeding the set threshold value are extracted from the first image data. The defect candidate area selecting means for selecting a defect candidate area on the inspection surface by performing image processing can be provided in a computer such as a PC as described above. By providing such means, it becomes possible to select the defect candidate area. Also,
The computer may also be provided with means for specifying a defective area on the inspection surface by further performing image processing only on the area based on the data in which the information of each position of the area selected in the defect candidate area selection is recorded. it can. By using the appearance inspection apparatus of the present invention equipped with such means, the above-described appearance inspection method for electronic circuit parts can be performed. Further, when it is necessary to coordinate the data corresponding to the output value of the detection output that is output from the color light receiving unit into a different coordinate system to create new data, an arithmetic process for converting the coordinate and The computer can be equipped with a means for creating data consisting of the processing result of the arithmetic processing.

The appearance inspection method and the appearance inspection apparatus for electronic circuit parts according to the present invention have been described so far. next,
A method of manufacturing an electronic circuit component of the present invention having an external appearance inspection step of performing an external appearance inspection of an electronic circuit component by such an external appearance inspection method will be described. First, in the step of forming the wiring pattern on the substrate, the wiring pattern is formed according to the element function of the electronic circuit component. With respect to the appearance on the substrate on which such a wiring pattern is formed, it is necessary to perform an appearance inspection for defective areas such as adhesion of foreign matter, discoloration, cracks, and surface peeling. Therefore, the visual inspection of the inspection surface on the substrate on which the wiring pattern is formed is performed in the determination step using the above-described visual inspection method. In the determination step, first, a defect candidate area is selected by the image processing of the first step using the same method as the appearance inspection method described above, and the second step is selected only for the selected defect candidate area. By sequentially performing the image processing of, the defective area on the inspection surface on the substrate is specified. Then, the shape, such as the area and the length, of each portion of the wiring pattern corresponding to the identified defective area is evaluated, so that the final defect determination / selection is performed. By performing the determination process for the appearance of the inspection surface on the board in such a work process,
The processing accuracy and processing speed of the appearance inspection can be improved. As a result, it is possible to improve the yield of manufactured electronic circuit parts and to increase the manufacturing efficiency thereof.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram showing an embodiment of an appearance inspection apparatus for electronic circuit parts of the present invention. The visual inspection apparatus 100 includes a stage 20 on which the electronic circuit component 1 is placed. Also, stage 20
Can automatically position and carry the electronic circuit component 1 by electric power from the movement control device 50. The visual inspection apparatus 100 is configured to further include an illuminating device 40 for illuminating the inspection surface of the electronic circuit component 1 with light from the light source 30, a color light receiving unit 2, an image processing device 11, and the like. . The color light receiving unit 2 captures a color image of the appearance of the inspection surface of the electronic circuit component 1 to be subjected to the appearance inspection, and detects the input signal of the color image at each pixel corresponding to each position on the inspection surface. Together with 3 in the three-dimensional color space coordinate system that represents the color image at each pixel.
It has a function of outputting a detection output signal corresponding to each of the two coordinate components to the image processing apparatus 11. Next, as shown in FIG. 3, the image processing apparatus 11 includes a CPU 13 having a function of arithmetic processing and the like, a memory 14 having a function of storing data,
The signals of the detection output corresponding to each of the three coordinate components of the three-dimensional color space coordinate system representing the color image, which are output from the hard disk 15 having the function of storing and accumulating data and the color light receiving unit 2, are taken in, and their analogs An image capturing board 16 having a function of A / D converting a signal into a digital signal, a monitor 12 for displaying a captured image, a processing state, and the like are provided. With such an image processing device 11, image data creation, image processing, and the like can be performed. The form of the image processing apparatus 11 in FIGS. 1 and 3 is a personal computer (P
Although C) is mainly used, a general-purpose computer such as a workstation can be used instead of the PC. Further, an image processing apparatus specialized in image capturing and processing functions can be made to function in a form of being externally connected to a computer. Further, although the hard disk 15 is positioned as the auxiliary storage device here, the hard disk as the auxiliary storage device is MO,
Reambal storage medium such as CD-ROM, or LA
It can also be replaced with an external storage medium connected by N or the like. On the other hand, the memory 14 is used for storing image data, image processing, arithmetic processing, and the like, but the hard disk 15 can of course perform the functions of these memories 14.

Next, the appearance inspection method of the present invention will be described with reference to FIGS. 1, 2 and 3. FIG. 2 shows a work procedure of the appearance inspection method. Stage 2
The inspection surface of the electronic circuit component 1 placed on 0 is irradiated with light from the light source 30 through the illumination device 40, and a color image of the appearance of the inspection surface of the electronic circuit component 1 is displayed in the color light receiving unit. 2 and outputs a detection output signal corresponding to each of the three coordinate components of the three-dimensional color space coordinate system representing the color image to the image processing device 11 at each pixel corresponding to each position on the inspection surface. To do. Then, the image capturing board 16 of the image processing apparatus 11 A / D-converts the input detection output signal and generates inspection surface color information as a digital signal. This inspection surface color information corresponds to three independent coordinate components of the three-dimensional color space coordinate system at each position on the inspection surface, that is, at each pixel position that partitions the color image of the appearance of the inspection surface. It is composed of one color space coordinate value. As described above, the inspection surface color information includes the position information of each position on the inspection surface and the color image information at each position. Such inspection surface color information is captured in the image processing apparatus 11 via the image capturing board 16 as information of the color image of the inspection surface. This work corresponds to step 1.

The inspection surface color information input to the image processing apparatus 11 in step 1 is stored in the memory 14 of the image processing apparatus 11 as a first inspection image. Then, in comparison with the reference image that has been read in the memory 14 in advance, if there is a positional deviation in the first inspection image, the image processing device 11 calculates the amount of deviation. After that, the position of the first inspection image is corrected based on the deviation amount, and the first inspection image is stored in the memory 14.
This work corresponds to step 2.

In step 2, the first inspection image stored in the memory 14 has the same information as the inspection surface color information, and 3 of the color image information at each position of the inspection surface forming the inspection surface color information. 3 for each of the three coordinate components
It consists of coordinate components. Next, of the three coordinate components representing each of the three coordinate components, the image processing apparatus 11 creates the inspection surface color data including at least one coordinate component. In addition, a first non-defective item reference value is set in advance for each coordinate component of the color image information at each position of the inspecting surface that constitutes the inspection surface color information, and a first non-defective item including these first non-defective item reference values The reference color information is read into the memory 14 in advance. Then, of the first non-defective item reference color information, the first non-defective item reference color data representing a coordinate component corresponding to the coordinate component of the inspection surface color data is created by the image processing device 11, and the first non-defective item reference color data is created. The difference of each coordinate component from the inspection surface color data is calculated by the CP of the image processing device 11.
Based on the calculation processing by the difference processing using the U13 and the memory 14, the first image data including the processing result is created. This work corresponds to step 3. afterwards,
Image processing of extracting data that exceeds a set threshold value from the first image data is performed. A set of each position on the inspection surface corresponding to the data extracted by this image processing is set as a defect candidate area. This work is Step 4
This corresponds to the selection of defect candidate areas.

The data extracted in step 4 has position information of each position of the defect candidate area. Therefore, this extracted data is stored in the memory 14 as the first extracted data, and in step 2, the memory 1
A comparison process with the first inspection image stored in No. 4 is performed to create a first extraction inspection image composed of three coordinate components representing each of the three coordinate components of the color image information at each position of the defect candidate area. The image processing device 11 further performs image processing based on the first extracted inspection image. In the defect determination processing by such image processing, the defective area on the inspection surface is specified. This work corresponds to the defective area identification in step 5.

By the work up to step 5, the defective area on the inspection surface is specified by the image processing divided into two steps. The image processing in step 4, which is the first stage, uses image data that has the same three-dimensional color space coordinate system as the detection output signal from the color light receiving unit.
As a result, it is possible to reduce the processing time of the image processing because the work of performing coordinate conversion is not required in the process of creating the image data. Further, a second stage image processing is performed to identify the defective area (step 5).
Is performed only on the defect candidate area selected in the first-step image processing (step 4), so that the processing time of the image processing can be reduced. Further, by performing the image processing in two steps, it is possible to improve the inspection accuracy of the appearance inspection on the inspection surface.

Next, after the work of step 5, by using the second extracted inspection image corresponding only to the specified defective area, each part of the electronic circuit component 1 which is the defective area is inspected. The area and length are analyzed by the image processing device 11 to create shape evaluation data. If a shape exceeding the threshold value set for each part of the wiring pattern formed on the inspection surface of the electronic circuit component 1 is extracted from the shape evaluation data, the electronic circuit component 1 is determined to be defective. judge. This work corresponds to the quality judgment by the shape evaluation in step 6.

According to the above work procedure, the electronic circuit component 1
However, this work procedure is only an example. Known methods can be applied to the position correction of step 2, the method / procedure of data creation, arithmetic processing and analysis in the image processing apparatus 11, and the like. Also, step 4
In the image processing of, for example, it is also possible to perform the same image processing by exchanging the values of the first non-defective item reference value and the set threshold value, respectively.

Next, an embodiment of the appearance inspection method of the present invention will be described below together with a specific example of a three-dimensional color space coordinate system used for image data and a specific example of specifying a defective area in step 5. .

(Embodiment 1) As the color light receiving portion 2, one that can capture a color image for each of the three primary colors of light (red R, green G, blue B) is used. For example, a CCD type three-plate color line sensor camera or the like is used. By using the line sensor camera 2 as described above, as shown in FIG. 4, the stage 20 on which the electronic circuit component 1 is mounted is moved in the X direction, which is a direction perpendicular to the camera scanning direction. Color images of the appearance of the inspection surface of the component 1 for R, G,
It is taken into the image processing apparatus 11 as inspection surface color information for each B. As shown in FIG. 4, each captured image for each of R, G, and B is configured with a pixel as a minimum unit, and the size of each pixel is determined by the type of the line sensor camera 2 and the type of lens used. It is specified by the resolution. On the other hand, R,
The image processing device 11 from the line sensor camera 2 for each of G and B
The magnitude of the brightness that represents the output value of the detection output that is output to
In the image processing apparatus 11, for example, it is converted into a 1-byte digital value of 0 to 255. In this way, at each pixel position corresponding to each position on the inspection surface,
The inspection surface color information composed of color space coordinate values corresponding to each of the R, G, and B coordinate components is taken into the image processing device 11, and the inspection surface color information is the position information of each position of the inspection surface and The color image information represented by the RGB coordinate system at the position is included.

Next, the inspection surface color information input to the image processing apparatus 11 is stored in the memory 14 of the image processing apparatus 11 as the first inspection image. Then, it is compared with the reference image that has been read into the memory 14 in advance, and if there is a positional deviation in the first inspection image, the image processing device 11 calculates the amount of deviation. After that, the position of the first inspection image is corrected based on the deviation amount, and the first inspection image is stored in the memory 14.

After performing the above position correction, of the R, G, and B coordinate components representing the color image information at each position of the inspection surface in the first inspection image stored in the memory 14,
The image processing apparatus 11 creates inspection surface color data including at least one coordinate component. Further, a first non-defective item reference value is set in advance for each of the R, G, and B coordinate components at each position on the inspection surface, and the first non-defective item reference color information including these first non-defective item reference values is stored in advance in a memory. 14 read it. Then, of the first non-defective item reference color information, the first non-defective item reference color data representing a coordinate component corresponding to the coordinate component of the inspection surface color data is created by the image processing device 11, and the first non-defective item reference color data is created. The difference of each coordinate component from the inspection surface color data is obtained by the difference processing using the CPU 13 and the memory 14, and the first image data composed of the processing result is created. After that, image processing is performed to extract, from the first image data, those exceeding a set threshold value. A set of each position on the inspection surface corresponding to the data extracted by this image processing is set as a defect candidate area. Further, by setting the threshold value set in the image processing to at least the acceptable range for non-defective products, the defect candidate region selected on the basis of the extracted data includes at least the defect region. can do.

The defect candidate area is selected for at least one color image among R, G, and B color images of the appearance of the inspection surface. For example, when the appearance is close to green (G) color, image processing is performed using the inspection surface color data of only the G coordinate component in the first inspection image. Or, if the appearance is close to white,
A coordinate component forming inspection plane color data created for image processing, such as performing image processing using inspection plane color data composed of three coordinate components of R, G, and B coordinate components of the first inspection image. The type and the number of coordinate components are selected appropriately.

Next, the data extracted by the image processing for selecting the defective area is stored in the memory 14 as the first extracted data and is compared with the first inspection image stored in the memory 14. Then, a first extraction inspection image including three coordinate components representing the R, G, and B coordinate components of the color image information at each position of the defect candidate area is created. Next, the first extracted inspection image including the R, G, and B coordinate components is subjected to coordinate conversion using the CPU 13 and the memory 14 into the HSI coordinate system having the hue H, the saturation S, and the lightness I as coordinate components. The defective area specific color information is generated and stored in the memory 14 as the second inspection image. This defective area specific color information, that is, the second inspection image, includes position information of each position of the defective candidate area and H at each position.
It includes color image information represented by the SI coordinate system. Further, the hue H represents a hue, and as shown in FIG. 5A, R (red), Y in the circumferential direction.
(Yellow), G (green), C (cyan), B (blue), and M (magenta) are defined, and the hue is defined by the angle with respect to the center. Therefore, 0 to indicate the hue
The color space coordinate value of the H coordinate component is obtained by allocating an angle in the range of 360 degrees to a value of 0 to 255 (1 byte). For example, if R is 0, G is 85 and B is 1.
It becomes 70 and becomes R again at 255. Next, FIG. 5 (b)
As shown in the HSI coordinate system, the saturation S, which represents the vividness of the color, is defined by the length from the center. Therefore, the value obtained by allocating the length to a value of 0 to 255 (1 byte) is used as the color space coordinate value of the S coordinate component. Finally, the lightness I, which represents the brightness of a color, is defined by the position on the central axis. Therefore, the position is 0-255
The value allocated to (1 byte) is used as the color space coordinate value of the I coordinate component.

Using the second inspection image in which the color space coordinate values of the respective coordinate components are defined as described above, image processing, which is a defect determination process for specifying a defective region, is performed in the following procedure. . First, defective area specifying color data consisting of at least one coordinate component among H, S, and I coordinate components representing color image information at each position of the defective candidate area in the second inspection image stored in the memory 14 is imaged. Created in process 11. Further, a second non-defective item reference value is set in advance for each of the H, S, and I coordinate components at each position on the inspection surface, and all the second non-defective item reference color information including these second non-defective item reference values is set in advance. The H, S, and I coordinate components at each position of the defect candidate area are read by the memory 14 and the comparison processing of the all second non-defective item reference color information and the first extracted data stored in the memory 14 is performed. Second non-defective item reference color information composed of preset second non-defective item reference values is created and stored in the memory 14. And, of the second non-defective item reference color information,
The image processing apparatus 11 creates second non-defective item reference color data representing a coordinate component corresponding to the coordinate component of the defective region specific color data, and each coordinate component of the second non-defective item reference color data and the defective region specific color data. The difference is calculated based on the difference processing using the CPU 13 and the memory 14, and the second image data including the processing result is created. After that, image processing corresponding to the defect determination processing is performed, in which those exceeding the set threshold value are extracted from the second image data. A set of respective positions on the inspection surface corresponding to the data extracted by this image processing is defined as a defective area. Further, by setting the threshold value set in the image processing to be within the acceptable range of non-defective products, the defective area can be specified with high accuracy. Image processing for identifying the defective area is performed by such a procedure. Also in this image processing, the type of coordinate components and the number of coordinate components forming the defective area specifying color data used may be appropriately selected in consideration of the required specifying accuracy for specifying the defective area. Good.

Although the defect candidate area selection and the defect area identification are performed by the method as described above, the first image data used for the image processing in the defect candidate area selection corresponds to the RGB coordinate system. On the other hand, the second image data used for the image processing for specifying the defective area corresponds to the HSI coordinate system. By selecting such a three-dimensional color space coordinate system, the first image data used for the image processing for selecting the defect candidate area is converted into the same three-dimensional color space coordinate as the signal output as the detection output from the color light receiving unit. On the other hand, in the second image data used for the image processing for specifying the defective area, on the other hand, when setting the good product reference value,
It is possible to use a three-dimensional color space coordinate system that is close to the color sense of the person who makes the visual judgment as the basis. As a result, the processing accuracy and processing speed of the visual inspection can be increased. Further, the coordinate conversion processing of the data into the HSI coordinate system required for specifying the defective area may be performed only on the data corresponding to the defective candidate area selected in the defective candidate area selection. Therefore, it is possible to significantly reduce the processing time as compared with the processing time required for the coordinate conversion processing to the HSI coordinate system which is conventionally required.

Next, the data extracted from the second image data in the image processing for specifying the defective area has positional information of each position of the defective area. Therefore, the extracted data is used as the second extracted data and stored in the memory 14 as the second extracted inspection image. And
Using the second extracted inspection image, the quality determination by the shape evaluation in step 6 shown in FIG. 2 is performed by the same method as described above to determine the final appearance quality.

Next, a case where the defective area is specified by the image processing by the pattern matching method using the image data corresponding to the RGB coordinate system will be described below as the second embodiment.

(Embodiment 2) The procedure until the defective area is specified is the same as that of the embodiment 1. Using the first extraction inspection image composed of three coordinate components representing each of the R, G, and B coordinate components of the color image information at each position of the defect candidate region selected in the defect candidate region selection of the first embodiment, the defect is detected. Specify the area. The first extracted inspection image includes color image information including color image information of each of the R coordinate component, the G coordinate component, and the B coordinate component, and position information of each position of the defect candidate area. Therefore, pattern data composed of three color pattern components each representing a non-defective product pattern for each of the R coordinate component, the G coordinate component, and the B coordinate component is created in advance, and at least one color pattern component and the color pattern component are created. Is compared with the coordinate component of the first extraction inspection image corresponding to (1) in the form corresponding to each position of the defect candidate area. In the image processing by the comparison processing, a defective area including defective defects other than the non-defective pattern is extracted as data. In this way, the defective area is specified.

The image processing by the pattern matching method is performed on at least one coordinate component of the first extracted inspection image. For example, when the image processing in selecting the defect candidate area is performed only on the G coordinate component,
Image processing by pattern matching method is used for R, G, B
It is possible to improve the specifying accuracy for specifying the defective area by performing the process for all the coordinate components. As described above, also in the image processing by the pattern matching method, the type of coordinate components and the number of coordinate components to be used may be appropriately selected in consideration of the required accuracy of identifying the defective area.

When the defective area is specified by the image processing according to the second embodiment, there is an advantage that the processing time of the image processing can be shortened as compared with the image processing using the HSI coordinate system in the first embodiment. Further, in the case of handling electronic circuit parts which can sufficiently secure the inspection accuracy of the appearance inspection on the inspection surface by the two-step appearance inspection method of selecting the defect candidate area and identifying the defect area according to the embodiment 2, the appearance of the embodiment 2 The inspection method becomes a particularly effective method.

By using the above-described appearance inspection method of the present invention, it becomes possible to increase the inspection accuracy and inspection speed of the appearance inspection performed on the inspection surface of the electronic circuit component. In addition, the wiring pattern corresponding to the element function of the electronic circuit component is formed on the substrate, the appearance process on the substrate, a determination step of visual inspection for foreign matter adhesion, discoloration, cracks, surface peeling, etc. In the manufacturing method of the electronic circuit component that has, by performing the determination step by using the same method as the appearance inspection method of the present invention, the inspection accuracy and inspection speed for the appearance can be improved.

The above-described embodiments and examples according to the present invention are merely examples, and the concept that the appearance inspection of the inspection surface of the electronic circuit component is performed by the image processing consisting of two steps is as follows. It is included in the concept of the invention.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of an appearance inspection device of the present invention.

FIG. 2 is a schematic process diagram showing one work procedure of the appearance inspection method of the present invention.

FIG. 3 is a schematic configuration diagram of a main part of an appearance inspection device of the present invention.

FIG. 4 is a schematic diagram for explaining the appearance inspection method of the present invention.

FIG. 5 is a schematic diagram for explaining a three-dimensional color space coordinate system used in the appearance inspection method of the present invention.

[Explanation of symbols]

1 Electronic circuit parts 2 Color receiver (line sensor camera) 11 Image processing device 100 Visual inspection device

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 2G020 AA08 DA02 DA03 DA04 DA05                       DA13 DA22 DA32 DA52                 2G051 AA61 AB07 AC21 CA03 CB01                       DA06 EA12 EA14 EA17 ED08                       ED11                 4M106 AA01 AA02 AA04 BA10 DB21                 5B057 AA03 BA02 CE18 DA03 DB02                       DB06 DB09 DC03 DC04 DC09                       DC25 DC33 DC36                 5L096 AA02 AA06 BA03 EA14 EA26                       FA59 FA64 FA69 GA08 GA38                       GA40 GA41 GA51 HA07 JA11

Claims (11)

[Claims] 1. A method for inspecting the appearance of an electronic circuit component, the inspection light from the inspection surface of the electronic circuit component being received by a color light receiving section, and the inspection surface being based on the detection output of the color light receiving section. Inspection surface color information composed of three coordinate components of the three-dimensional color space coordinate system at each position in the inside, and inspection surface color data representing at least one coordinate component of the inspection surface color information and a preset first conforming product standard Of the color information, a defect candidate area is selected based on a difference from the first non-defective item reference color data that represents the coordinate component corresponding to the inspection surface color data, and the defect determination processing is performed based on the selection result, thereby inspecting the inspection surface. The method of inspecting the appearance of an electronic circuit component, comprising: 2. With respect to the defect candidate region, a preliminary defect candidate region is extracted based on a difference between the inspection surface color data and the first non-defective item reference color data, and a defect candidate determination process is performed based on the extraction result. 2. The appearance inspection method for electronic circuit parts according to claim 1, wherein 3. The defect candidate determination processing generates inspection surface color information composed of three coordinate components of a three-dimensional color space coordinate system at each position in the inspection surface, and calculates three coordinate components of the inspection surface color information. A process for selecting a defective candidate area based on the difference between the inspection surface color data represented and the first non-defective product reference color data representing the coordinate component corresponding to the inspection surface color data among the preset first non-defective product reference color information. The method for inspecting the appearance of an electronic circuit component according to claim 2. 4. The defective area is specified using a three-dimensional color space coordinate system different from the three-dimensional color space coordinate system used for the inspection surface color information. 11. An appearance inspection method for electronic circuit parts according to any one of claims. 5. The defectiveness determination processing generates defective area specific color information including three coordinate components of a three-dimensional color space coordinate system at each position of the defective candidate area, and at least the defective area specific color information is generated. Defects based on the difference between the defective area specific color data representing one coordinate component and the second non-defective product reference color data representing the coordinate component corresponding to the defective area specific color data set in advance from the second non-defective product reference color information. 5. The appearance inspection method for electronic circuit parts according to claim 4, wherein the method is a process for specifying a region. 6. The defect determination processing generates defective region specific color information including three coordinate components of a three-dimensional color space coordinate system at each position of the defective candidate region, and the defective region specific color information is classified into three types. The defective area is defined based on the difference between the defective area specific color data that represents the coordinate component and the second non-defective product reference color data that represents the coordinate component that corresponds to the defective area specific color data that has been preset. The appearance inspection method for electronic circuit parts according to claim 4, wherein the method is a process for specifying. 7. The defect determination process is a process of extracting a preliminary defective region based on a difference between the defective region specifying color data and the second non-defective item reference color data, and specifying a defective region based on the extraction result. The appearance inspection method for electronic circuit parts according to claim 5 or 6, characterized in that 8. A three-dimensional color space coordinate system used for the inspection surface color information for selecting the defect candidate area has R as a coordinate component of red R, green G and blue B which are the three primary colors of light.
The appearance inspection method for electronic circuit parts according to any one of claims 1 to 7, wherein the appearance inspection method is of a GB coordinate system. 9. The three-dimensional color space coordinate system used in the defect determination process for specifying the defective area is hue H,
9. An HSI coordinate system having a saturation S and a lightness I as coordinate components, according to any one of claims 1 to 8.
The appearance inspection method for electronic circuit parts according to item 1. 10. A visual inspection device used for visual inspection of electronic circuit parts, comprising: a color light receiving part for imaging an inspection surface of the electronic circuit part; and the inspection surface based on a detection output of the color light receiving part. Inspection surface information generating means for generating inspection surface color information consisting of three coordinate components of a three-dimensional color space coordinate system at each position in the inside, and inspection surface color data representing at least one coordinate component of the inspection surface color information and preset Defective candidate area selecting means for selecting a defective candidate area based on a difference from the first non-defective item reference color data representing the coordinate component corresponding to the inspection surface color data in the selected first non-defective item reference color information; And a visual inspection device for electronic circuit parts, further comprising: defective area specifying means for specifying a defective area on the inspection surface by further performing image processing 11. A step of forming a wiring pattern on a substrate, and an inspection light from an inspection surface on the substrate on which the wiring pattern is formed is received by a color light receiving section, and based on a detection output of the color light receiving section. To generate inspection surface color information composed of three coordinate components of the three-dimensional color space coordinate system at each position on the inspection surface, and preset with inspection surface color data representing at least one coordinate component of the inspection surface color information. A defect candidate area is selected based on a difference from the first non-defective product reference color data representing the coordinate component corresponding to the inspection surface color data in the first non-defective product reference color information, and image processing is further performed only on this defective candidate area. And a determination step of determining a defective area on the inspection surface by the above, and determining / selecting a defective wiring pattern based on the specified defective area. The method of production.