JPH07119704B2 - Board inspection equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION << Industrial Application Field >> The present invention is to process an image obtained by picking up an image of a printed circuit board on which a component is mounted to process the presence / absence and position of the component on the printed circuit board to be inspected. More specifically, the present invention relates to a substrate inspection device that inspects a portion to be inspected on the printed circuit board by processing received light data obtained by receiving light from the printed circuit board.

<< Prior Art >> When an automatic mounting device is used when mounting various chip parts such as resistors and semiconductor elements on a printed circuit board, parts may not be mounted according to mount data after mounting.

For this reason, when using such an automatic mounting device, the printed circuit board is checked after mounting, and a proper chip part is mounted in a correct position (position, direction) at a proper position on the printed circuit board. Whether or not
In addition, it is necessary to inspect whether it has fallen out.

However, if such an inspection is performed by visual inspection by hand as in the conventional case, there is a problem that the occurrence of an inspection error cannot be completely eliminated and the inspection speed cannot be increased.

Therefore, in recent years, various manufacturers have proposed various automatic inspection devices for printed circuit boards that can automatically perform this type of inspection.

FIG. 4 is a block diagram showing an example of such an automatic inspection device.

The automatic inspection apparatus shown in this figure compares all of the components 2-on the printed circuit board 1 to be inspected by comparing the pre-input reference data with the inspection data obtained by imaging the printed circuit board 1 to be inspected. Whether 1 to 2-n is loaded,
And these parts 2-1 to 2-n are automatically inspected for any displacement or the like.
Keyboard 3, storage unit 4, TV camera 5, and processing unit 6
And a display unit 7.

The keyboard 3 is provided with various keys such as a function key and a numeric keypad, and is used as reference data when inspecting the inspected printed circuit board 1 by an operator or the like, that is, the type data of the inspected printed circuit board 1 and the inspected printed circuit board. 1 such as color data, mounting position data, mounting attitude data, shape data, etc. of the components 2-1 to 2-n, and each of the above-mentioned printed circuit boards 1 to be inspected based on these characteristic data. When the permissible error value data and the like necessary for inspecting the quality of the components 2-1 to 2-n are input, these data are supplied to the storage unit 4.

The storage unit 4 includes a RAM (random access memory) or the like, stores each data supplied from the keyboard 3 and supplies the data to the processing unit 6.

The processing unit 6 processes the image of the inspected printed circuit board 1 obtained by the TV camera 5, and features of each of the components 2-1 to 2-n mounted on the inspected printed circuit board 1. Data (inspected data) is extracted, and the inspected data is checked based on the reference data stored in the storage unit 4 and the check result is displayed on the display unit 7.
To display the quality of each of the parts 2-1 to 2-n.

<< Problems to be Solved by the Invention >> In such a conventional automatic inspection apparatus, if the reference data is input only once from the keyboard 3, the reference data is held in the storage unit 4. Therefore, when the inspected printed circuit board 1 is inspected, if the inspection result of each of the components 2-1 to 2-n is incorrect, there is a problem that correct reference data must be re-input from the keyboard 3.

In view of the above circumstances, it is an object of the present invention to provide a board inspection apparatus that can easily change reference data according to the processing result of each component obtained by processing an image of a printed board.

<< Means for Solving the Problems >> In order to solve the above problems, the board inspection apparatus according to the present invention processes the received light data obtained by receiving the light from the printed board to inspect the printed area on the printed board. In the board inspection apparatus for inspecting, the processing means having a first determination standard for inspection, determining the received light data based on the first determination standard, and visually outputting a determination result; Information input means for inputting an instruction to move the reference up and down by a predetermined amount; and the first input terminal based on the instruction from the information input means.
And a processing content changing means for changing the determination criterion of and determining the received light data again.

<< Embodiment >> FIG. 1 is a block diagram showing an embodiment of the substrate inspection apparatus according to the present invention.

In the component mounting board inspection apparatus shown in this figure, when the characteristic parameters are extracted from the image data obtained by imaging the reference printed circuit board 10-1 and displayed, the operator who sees this display correctly makes this extraction. The XY table unit 13 is designed to automatically correct the reference data (first determination criterion) used when extracting the characteristic parameters by simply inputting information as to whether or not the characteristic parameter is extracted. And the imaging unit
14, a processing unit 15, a determination result output unit 16, and an information input unit 17
A table controller 18 and an imaging controller 19.

The XY table unit 13 includes two pulse motors 20 and 21 controlled by a table controller 18, and a table 22 driven in the X-axis direction and the Y-axis direction by the pulse motors 20 and 21. And the reference printed circuit board 10-1 (or the printed circuit board to be inspected) placed on the table 22.
10-2) and a check mechanism 23 for fixing the reference printed circuit board 10-1 mounted on the table 22.
(Or the printed circuit board 10-2 to be inspected) is fixed by the chuck mechanism 23, and then the pulse motors 20, 2
The position in the X-axis direction and the Y-axis direction is determined by 1,
The image is taken by the imaging unit 14.

The image pickup section 14 is arranged above the XY table section 13, and its focus, magnification, sensitivity, etc. are controlled by a control signal output from the image pickup controller 19, which is a TV camera 25.
And a ring lighting device 26 which is arranged coaxially with respect to the TV camera 25 and whose brightness and the like are controlled by a control signal output from the image pickup controller 19. The image signal (analog signal) as the received light data obtained by the camera 25 is supplied to the processing unit 15.

In addition, the information input unit 17 determines the type of the reference printed circuit board 10-1 (for example, the substrate number, etc.), the reference printed circuit board 10-
Input information such as data on the types, numbers of parts, positions, etc. of the parts 11-1a to 11-na mounted on the unit 1 and processing procedures (for example, reference data when extracting parameters and processing quality information). A keyboard, a mouse, and the like for this purpose are provided, and the data and operation information input from here are supplied to the processing unit 15.

The processing unit 15 has a teaching mode and an inspection mode. In the teaching mode, a characteristic parameter (reference parameter) is obtained from the image signal (image signal of the reference printed circuit board 10-1) supplied from the imaging unit 14. Extraction, while displaying this on the determination result output unit 16, if the operator who sees this display instructs to re-extract the characteristic parameters, the reference data used when extracting the characteristic parameters from the image signal. The image signal supplied from the image pickup unit 14 based on the reference data obtained in the teaching mode (the image signal of the inspected printed circuit board 10-2) is corrected. ), A characteristic parameter (inspected parameter) is extracted from the And whether or not all of the components 11-1b to 11-nb are present on the inspected printed circuit board 10-2, and whether or not each of these components 11-1b to 11-nb is displaced. The image input unit 27, the image processing unit 28, and the memory 29.
And a determination unit 30 and a control unit 31.

The image input unit 27 performs A / D conversion on the image signal supplied from the image pickup unit 14 and performs various correction processes (for example, shading correction) to perform the reference print circuit board.
10-1 is for creating image data (data obtained by correcting and quantizing image signals) of the inspected printed circuit board 10-2, and the reference printed circuit board 10-1 and the inspected printed circuit board obtained here. The image data regarding 10-2 is the control unit.
It is supplied to 31 etc.

Further, in the teaching mode, the image processing unit 28 changes the reference data (binarization threshold value data in this embodiment) based on the processing instruction signal supplied from the control unit 31, while controlling the control unit 31. From the image data of the reference printed circuit board 10-1 supplied via the respective parts 11-1a to 11-na
Of the printed circuit board 10-2 to be inspected supplied through the control unit 31 based on the reference data used last in the teaching mode in the inspection mode. Characteristic parameters (parameters to be inspected) of each of the components 11-1b to 11-na are extracted from the image data, and the reference printed circuit board 10-1 (or the printed circuit board to be inspected) obtained here is extracted.
Parameters related to 10-2) are the control unit 31 and the determination unit.
Supplied to 30 etc.

In addition, the memory 29 is from the control unit 31 to the reference printed circuit board.
10-1 Image data, characteristic parameters (reference parameters) of each component 11-1a to 11-na on this reference printed circuit board 10-1, and reference data necessary for extracting these characteristic parameters are supplied. When the transfer request is issued from the control unit 31, the reference parameters and the like are supplied to the image processing unit 28, the determination unit 30, and the like.

The determination unit 30 compares the reference parameter output from the memory 29 in the inspection mode with the inspection parameter obtained by the image processing unit 28 supplied via the control unit 31 to obtain the inspection target. Inspection printed circuit board 10-2 parts 11-1b to 11
-Whether nb is missing, and these parts 11-
It is to determine whether or not 1b to 11-nb have a posture deviation, and the determination result is supplied to the control unit 31 and the like.

The control unit 31 includes a microcomputer and the like, and the image input unit 27, the image processing unit 28, the memory 29, and the determination unit based on the information input from the information input unit 27 and a program input in advance. 30 Controls each part of the device.

The determination result output unit 16 is configured to include a CRT (CRT display), a printer, etc.
31 is supplied with the reference parameters and inspection parameters, is supplied with the image data of the reference printed circuit board 10-1, the inspection printed circuit board 10-2, and is supplied with the judgment result, and is displayed and printed out. To do

Further, the table controller 18 includes the controller 31 and the X
An interface or the like for connecting to the -Y table unit 13 is provided, and the data obtained by the XY table unit 13 is supplied to the control unit 31 or a control signal supplied from the control unit 31 is supplied. Based on this, the XY table unit 13 is controlled.

The image pickup controller 19 includes the control unit 31 and the image pickup unit.
The control unit 31 controls the image pickup unit 14 based on a control signal supplied from the control unit 31.

Next, the operation of this embodiment will be described separately for the teaching mode and the inspection mode.

First, in the teaching mode, the flow chart step ST1 shown in FIG. 2 (A) is executed to set each part of the apparatus to the teaching mode and the step ST1.
At 2, the card number and reference data of the reference printed circuit board 10-1 are input from the information input unit 17.

Then, when each of these data is input, the control unit 31 fetches each of these data from the information input unit 17, stores them in the memory 19, and displays a part of these data (reference data) as an image. It is supplied to the processing unit 28.

Next, when the reference printed circuit board 10-1 is placed on the table 22 of the XY table unit 13, the control unit 31 makes a step ST.
The check mechanism 23, the pulse motors 20 and 21, the ring lighting device 26, and the TV camera 25 are controlled by 3 to control this TV camera.
The reference printed circuit board 10-1 obtained by the TV camera 25 while the reference printed circuit board 10-1 is imaged by the 25
The -1 image signal is converted into image data by the image input unit 27, the conversion result (reference substrate image data) is transferred to the image processing unit 28 in step ST4, and the parameter extraction determination routine 35 is executed.

In the parameter extraction determination routine 35, the image processing unit 28
In step ST5 shown in FIG. 2 (B), the reference board image data is set to 2 using the reference data (initial threshold TH1).
This is binarized in step ST6 (binarized image)
Is sent to the control unit 31 and is displayed on the determination result output unit 16 as a processing means for visually outputting the determination result.

In this case, as shown in FIG. 3A, one of the component images 36-1 to 36-n indicated by the reference board image data is one component image 36-i (1 ≦ i ≦ n). Is dark and the other one component 36-j (1≤j≤n, i ≠ j) is thin, and one scan line a including these component images 36-i, 36-j
In the case where the intensity of the signal is as shown in FIG. 3 (B), if the initial threshold value TH1 of the reference data is high,
The judgment result output unit 16 displays the binarized image PA shown in FIG.
1 is displayed.

When the display of the binarized image PA1 is completed, the image processing unit 28 asks the determination result output unit 16 in step ST7 whether or not the binarization process is correctly performed.
"G" is displayed, and at ST8, input is awaited.

Here, if the operator judges that the component area is too small by looking at the binarized image PA1 displayed on the screen of the determination result output unit 16 and presses the NG too small key of the information input unit 17, image processing is performed. The unit 28 proceeds from step ST18 to step ST9, where it detects that the key pressed by the operator is one of the NG keys, and branches from ST9 to ST10-.

Then, the image processing unit 28, in this step ST10, detects that the key pressed by the operator is an NG too small key, branches from this step ST10 to step ST11, and here the correction value K from the threshold value TH1. / n (where K is a constant and n is the number of corrections) is subtracted to obtain a new threshold value TH2, and step S
At T12, it is checked whether the threshold TH1 up to that point and the new threshold TH2 are inconsistent. Therefore, the information input unit 17
Is an information input means for inputting an instruction to move the reference data up and down by a predetermined amount, and the image processing means 28 changes the reference data according to the instruction of the information input means and changes the processing content to re-determine the image data. Constitutes a means.

Then, if there is a contradiction between the threshold TH1 and the new threshold TH2 so far, the image processing unit 28 branches from this step ST12 to step ST13, and the contradiction has occurred in the determination result output unit 16 here. Is displayed, the operation is terminated, and if there is no contradiction between the threshold TH1 and the new threshold TH2 up to that point, the steps ST12 to ST
Returning to 5, the binarization process described above is executed again using a new threshold value.

Then, the judgment result output unit 16 displays a binarized image PAn as shown in FIG. 3D, that is, a binarized image including both the component images 36-i and 36-j. When the operator viewing the image PAn presses the GO key of the information input unit 17, the image processing unit 28 branches from the step ST9 to the step ST14,
Here, the newest threshold value, that is, the threshold value THn used when obtaining the binarized image PAn is stored as the optimum threshold value, and then the operation is ended.

In the binarization process described above, the determination result output unit 16 displays a binarized image PA1 having a component area larger than the actual component area, as shown in FIG. 3 (E). If the operator who saw PA1 presses the NG excessive key of the information input unit 17, the image processing unit 28 executes step ST15 instead of step ST11, and adds the correction value K / n to the threshold value TH1 up to that point. After obtaining a new threshold value TH2, the process proceeds to step ST12.

That is, in this parameter extraction determination routine 35, the operator who sees the binarized image displayed on the determination result output unit 16 simply presses either the NG too small key or the NG too large key,
The threshold can be modified.

Next, when the processing of the parameter extraction determination routine 35 is completed, the control unit 31 proceeds to step ST16 of FIG. 2A to obtain the binarized image obtained by the parameter extraction determination routine 35.
The memory 29 stores the PAn as a reference parameter file and the optimum threshold THn as reference data.

Further, in the inspection mode, the control unit 31 executes step ST18 of the flowchart shown in FIG. 2 (C) to set each part of the apparatus to the inspection mode, and then in step ST19, the memory is stored.
The reference data stored in 29 is transferred to the image processing unit 28, and the reference parameter file stored in the memory 29 is transferred to the determination unit 30.

Next, when the inspected printed circuit board 10-2 is placed on the table 22 of the X = Y table section 13, the control section 31 operates the check mechanism 23 at step ST20 to move the inspected printed circuit board 10-2. Fixed, then each pulse motor 20,2
1 is controlled to determine the position in the X-axis direction and the position in the Y-axis direction of the printed circuit board 10-2 to be inspected, and the brightness of the ring illumination device 26, the imaging condition of the TV camera 25, etc. are adjusted.

Next, in step ST21, the control unit 31 causes the TV camera 25 to capture an image of the printed circuit board 10-2 to be inspected and operates the image input unit 27 to cause the TV camera 25 to obtain the printed circuit board 10 to be inspected. Image data (inspected board image data) is created from the image signal of -2, and is transferred to the image processing unit 28, and the inspected board image data is obtained at the optimum threshold value THn indicated by the reference data in step ST22. Perform binarization processing.

Next, the control unit 31 proceeds to step ST23, and the image processing unit 28
The binarized result (binarized image) obtained in step 1 is transferred to the determination unit 30 as an inspection parameter file, and the inspection parameter file is compared with the reference parameter file to inspect the printed circuit board 10-2. Parts 11-1b to 11-nb
Is missing, and these parts 11-1b ~
It is determined whether 11-nb is misaligned or not, and in step ST24 the determination result is supplied to the determination result output unit 16 and displayed.

As described above, in this embodiment, when the teaching mode is set, the reference data is changed only by pressing the excessive NG key or the excessive NG key.
And can be easily modified.

Further, since the processing result when the reference image is binarized based on this reference data is displayed on the image of the determination result output unit 16, even an unskilled operator can optimize the reference data. .

Moreover, since the past value is taken into consideration when correcting the reference data, the degree of correction can be made appropriate.

Further, in the above-described embodiment, the reference data is corrected in the teaching mode, but the reference data may be corrected in the inspection mode. At this time, the operator may erroneously recognize, that is, the normally mounted component is determined to be abnormal by the apparatus, or the opposite board may be set in the apparatus and the same processing may be performed.

Further, in the above-described embodiment, the image processing unit 28 and the determination unit
Although the image processing and the parameter determination processing are performed by 30, the processing performed by the image processing unit 28 and the determination unit 30 may be performed by the program of the control unit 31.

Further, in the above-described embodiment, the reference data is 2
Although the threshold value is used, the judgment values such as the color, the position, and the allowable error value may be corrected as the reference data.

<< Effects of the Invention >> As described above, according to the present invention, the light reception data obtained by receiving the light from the printed circuit board is determined by the first determination criterion for inspection and visually output. Since the first criterion is changed up and down by a predetermined amount and the received light data is re-determined based on the changed criterion, the criterion is increased or decreased based on the output result. Therefore, the amount of change is defined by a predetermined amount that is set in advance, and it is possible to obtain the optimum reference data by changing the determination criteria without hesitation. .

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the substrate inspection apparatus according to the present invention, FIGS. 2 (A) to 2 (C) are flow charts showing operation examples of the embodiment, and FIGS. E) is a schematic diagram for explaining the same embodiment, and FIG. 4 is a block diagram showing an example of a conventional automatic inspection device. 10-1 ... Printed circuit board (reference printed circuit board), 10-2
…… Printed circuit board (printed circuit board to be inspected), 14 …… Imaging section, 17 …… Processing content change section (information input section).

Claims (1)

[Claims] 1. A board inspection apparatus for processing received light data obtained by receiving light from a printed board to inspect an inspection site on the printed board, having a first judgment standard for inspection. A processing means for judging the received light data based on the first judgment criterion and visually outputting a judgment result; an information input means for inputting an instruction to increase or decrease the judgment criterion by a predetermined amount; A substrate inspection apparatus comprising: a processing content changing unit that changes the first determination criterion and re-determines the received light data based on an instruction.