JPS63124949A - Inspection device for substrate - Google Patents

Abstract

PURPOSE:To improve the acceptance/rejection decision accuracy for a copper foil pattern by mixing a fluorescent agent with a substrate base previously and recognizing a fluorescent part and a nonfluorescent part when the substrate is lighted. CONSTITUTION:A reference substrate 5a and a substrate 5b to be inspected are formed by sticking copper foil on the substrate base 7 formed in a plate shape by mixing the daylight excited fluorescent agent 8 with glass epoxy resin, etc., and carrying out etching, etc. A substrate inspection device consists of a lighting part 1 which lights the substrates 5a and 5b, an X-Y table part 2, an image pickup part 3, and a processing part 4. A decision data file is generated first based on the picked-up image of the reference substrate 5a. Then a data file to be inspected is generated next based on the picked-up image of the substrate 5b to be inspected. Then, respective data in the data file to be inspected are inspected based on said decision data file to decide whether or not the copper foil pattern 10 and a substrate mark 11 formed on the substrate 5b to be inspected are normal.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a board inspection device for inspecting the condition of a pattern of a steel part of a printed circuit board.

(Prior Art) As a board inspection device for inspecting the quality of a copper foil pattern formed on a printed circuit board, a reflected light detection type is conventionally known.

This type of board inspection device includes an illumination unit that illuminates a printed circuit board (hereinafter referred to as a board), a TV camera that takes an image of the board illuminated by this illumination unit, and a It is equipped with a processing section that processes an image to determine the quality of the copper foil pattern on the board, and a CRT display that displays the judgment result of this processing section,
The quality of the copper foil pattern formed on the substrate is inspected, and the inspection results are displayed on a CRT display.

In this case, the copper foil pattern formed on the substrate is the sixth
If formed correctly as shown in Figure (A), this copper foil pattern will be displayed in green, and in Figures 6 (B) to (F).
), if there is a defect 38, this portion is displayed in red.

(Problems to be Solved by the Invention) By the way, in such a conventional board inspection device, the board is illuminated by the illumination section, and the resulting foul light image (reflected light image from the board) is captured by a TV camera. Therefore, if the copper foil pattern formed on the board P is discolored or has irregularities, the S/N ratio of the electrical signal output from the TV camera will be small. Nari, α
There have been cases where it has become impossible to distinguish between the copper foil pattern portion of the board and other portions on the continuous portion side, and it has become impossible to determine whether the copper foil pattern is good or bad.

In view of the above problems, the present invention makes it possible to easily distinguish between the copper foil pattern portion and other portions even when the copper foil pattern is discolored or uneven. It is an object of the present invention to provide a board inspection device that can improve inspection accuracy and also identify marks formed on a board.

(Means for Solving the Problems) In order to solve the above problems, a board inspection apparatus according to the present invention images a board including a board base and a metal foil pattern formed on the board base, The resulting 17 images are processed to inspect the condition of the metal foil pattern on the substrate.In the board inspection device, an illumination section is used to illuminate the substrate whose substrate base has been mixed with a daylight-exciting fluorescent agent in advance. , a metal foil formed on the 11 by recognizing a light image section that travels around the substrate illuminated by the illumination section, a fluorescent portion and a non-fluorescent portion of the image obtained by the imaging section; The present invention is characterized by comprising a processing section that inspects the state of the pattern.

(Embodiment) FIG. 1 is a block diagram showing an embodiment of a board inspection apparatus according to the present invention.

The board inspection apparatus shown in this figure includes an illumination section 1, an X-Y table section 2, an imaging section 3, and a processing section 4, and an image obtained by retracting a substrate 5a. Create a judgment data file based on the following.

In this process, a data file to be inspected is created based on the optical images of the board 5b to be inspected, and each data in the data file to be inspected is inspected based on the judgment data file. Inspection 1: The quality of the copper foil pattern 10 and the substrate plate 11 formed on the metal plate 5b is determined.

In this case, each of the substrates 5a and 5b is mounted on a substrate base 7 formed into a plate shape by mixing a daylight-exciting fluorescent agent 8 in glass epoxy resin, as shown in FIGS. 2(Δ) to (C). copper foil 9
surface 1i1ff for the raw board 6 made by pasting
It is manufactured by processing, edge resist printing, etching, substrate mark printing, etc. here,
The reason why the daylight-excited fluorescent agent 8 is mixed in the substrate base 7 is to prevent the daylight-excited fluorescent agent 8 from illuminating the substrates 5a and 5b with illumination light (for example, white illumination light) that includes light that causes This is to cause strong fluorescence to be emitted from parts other than the part where the copper foil pattern 10 is formed, that is, the part where the substrate base 7 is exposed.

The lighting section 1 also performs on/off control fa (or dimming control, etc.) based on the control signal supplied from the processing section 4.
It is equipped with a ring-shaped white light source 12 that illuminates the X-Y table section 2 with white illumination light obtained from the white light source 12. Each of the loaded substrates 5a and 5b is illuminated.

The X-Y table section 2 includes an X-Y table 13 on which each substrate 5a, 5b is set, two pulse motors 14a that drive the X-Y table 13 based on control signals from the processing section 4, 14b, and each substrate 5a, 5b set on the X-Y table 13-L is illuminated by white illumination light emitted from the illumination unit 1 while
A b1 image is formed by the FQ unit 3.

The imaging section 3 includes a color TV camera 21 that is controlled by a control signal from the processing section 4. The electrical signals (R, G, B color signals) are supplied to the processing section 4.

In this case, since daylight-excited fluorescent agent 8 is mixed in the substrate base 7 of each of these substrates 5a, 5b, white illumination light containing light that excites daylight-excited fluorescent agent 8 is used to illuminate each of these substrates 5a, 5b. 5b, only the exposed part of the substrate base 7, that is, the part where the copper foil pattern 10 is not formed, emits fluorescence, as shown in FIG. A signal of the same hue as the fluorescence of the output R, G, B color signal (or a signal of the closest hue),
For example, if we focus on the R color signal, the signal level is low in the copper foil pattern 10 part, and the signal level in the other parts (board base 7
The signal level will be higher in the exposed area).

Therefore, if this R color signal is binarized using the threshold value TH, only the silhouette image of the copper foil pattern 10 portion can be extracted from the images of the substrates 5a and 5b.

The processing section 4 includes an A/D conversion section 23, a memory 24, a teaching table 25, an image processing section 26, and a determination section 2.
2 and X-Y stage skit [Cola 27 and l! il
It is equipped with an image controller 28, a CRT display 31, a printer 29, a keyboard 30, and a control unit (CPU) 32. In the teaching mode, the image signal ( R, G, B color signals) are processed to create copper foil pattern 10 and board mark 1.
1 and creates a judgment data file based on the results of this processing. In addition, in the inspection mode, the image of the substrate 5b supplied from the image carrier 3 @
Copper foil pattern 1 by processing (R, G, B color signals)
0 and board marks 11 are extracted, and a data file to be inspected is created based on the results of this processing. This inspection data file is compared with the judgment data file, and based on the comparison result, the board 5b
It is determined whether the copper foil pattern 10 and board mark 11 are correctly formed thereon.

The A/D converter 23 receives R and G signals from the image carrier 3.

When the B color signal is supplied, it is A/D converted (analog-to-digital conversion) and supplied to the control section 32 .

Further, the memory 24 includes a RAM (random access memory) and the like, and is used as a work area for the control section 32 and the like.

The image processing unit 26 also controls R, G, and G images via the control unit 32.
, B color image data is supplied, this R, G, B
It is configured to process color image data to create various data, and each data that is multiplied by 1!7 is supplied to the control section 32 and the determination section 22.

Furthermore, the teaching table 25 is equipped with a floppy disk device, etc., and stores the data, files, etc. supplied with the storage command when it is supplied with the storage command from the control unit 32, and also stores the data, files, etc. supplied with this command, and also stores the data, files, etc. supplied with the storage command from the control unit 32. When output, the data and file damage corresponding to this request are read out and supplied to the control unit 32, determination unit 22, etc.

When the determination section 22 is supplied with the determination data file from the control section 32 and transferred the inspected data file from the image processing section 26 at the time of inspection, it compares and determines these and determines whether the copper foil is placed on the substrate 5b. It is configured to determine whether or not the pattern 10 and the board mark 11 are formed correctly, and the determination result is transmitted to the control section 32.
supply to.

Further, the image transport controller 28 is
2, the illumination section 1 and the imaging section 3, and controls the illumination section 1 and the imaging section 3 based on the output of the control section 32.

Further, the X-Y stage controller 27 includes the control unit 3
2 and the X-Y table section 2, and controls the x-y table section 2 based on the output of the control section 32.

Further, the CRT display 31 is equipped with a cathode ray tube (CRT), and when it is supplied with image data, determination results, key manual data, etc. from the control section 32, it displays these on the screen.

Further, when the printer 29 is supplied with the determination result etc. from the control section 32, it prints it out in two predetermined formats (format, g).

The keyboard 30 also provides operation information and each board 5a.

The keyboard 30 has various keys necessary for inputting data, etc. related to the keyboard 30, and information, data, etc. input from the keyboard 30 is supplied to the control section 32.

The control unit 32 includes a microprocessor and the like, and operates as described below.

First, when inspecting a new board 5b to be inspected, the control section 32 calls the teaching routine 33 of FIG. 4(B) in step STI of the main chart 70 as shown in FIG. 4(A), and executes this routine. After controlling each part of the device with the 33 Stella 1S 2 to turn on the illumination unit 1 and image carrier 3, and to set the image carrier conditions and data processing conditions,
In step ST3, the reference substrate 5a is placed on the X-Y table section 2.
Check if is set.

Then, when the reference substrate 5a is set on the X-Y table section 2, the control section 32 moves from step ST3 to step S.
After branching to T4 and controlling the X-Y table section 2 to position the first imaging area of the reference substrate 5a directly below the imaging section 3, in step ST5, the first imaging area of the reference substrate 5a is placed on the imaging section 3. In addition to transporting one image area, the R, G, and B color signals obtained by this imaging I & operation are transferred to the A/D converter 2.
This A/D conversion result (R,
G, B color image data) is stored in the memory 24 in real time.

In this case, the reference substrate 5a is illuminated with white light by the illumination unit 1, and fluorescence is generated from the portion of the L↓ quasi-substrate 5a other than the copper foil pattern 10 (the exposed portion of the substrate base 7). The signal level of the copper foil pattern 10 portion of the R color image data stored in 24 is low, and the signal level of the portion other than this copper foil pattern 10 is high.

Next, the control unit 32 controls the surface light memory 24 in step ST6.
Transfer the R, G, and f3 color image data stored in the image processing unit 26 to the image processing unit 26, binarize each pixel of the R color image data using a threshold value TH, and extract a silhouette image of the copper foil pattern 10. - and R in step ST7.
The color of the FA board mark 11 is recognized based on the color image data and color image data other than the R color image data, for example, the G color image data, and the color of the FA board mark 11 is recognized.
extract the feature parameters. In this case, the method of recognizing the color of the board mark 11 is to reduce the G color image data from the R color image data (7) (R-G
) Methods such as binarizing image data are used.

Next, the control unit 32 controls the image processing unit 2 in step ST8.
After creating judgment data based on each data and feature parameter iJ obtained in step 6 and storing this in the teaching table 25, the process returns from step ST9 to step ST4, and the remaining image carrying areas are Perform the following processing.

Then, when the processing for all the imaging areas is completed, the control unit 32 performs the steps ST9 to ST5TI.
The program branches to O, and after creating a determination data file based on each determination data stored in the teaching table 25, it is stored in the teaching table 25, and this teaching routine 33 is ended.

Further, when this teaching 33 is completed and the test mode is set, the control section 32 calls the test routine 34 of FIG.
5 and the keyboard 30, as well as the IO number (identification number) of the board to be inspected 5b, read out a judgment data file from the teaching table 25 and supply it to the judgment section 22. .

Thereafter, the control unit 32 checks whether the substrate to be inspected 5b has been set on the XY table unit 2 using the Stella 1S 13 after adjusting the transport rA conditions and data processing conditions.

If this is set, the control section 32 branches from step ST13 to step 5114, where X-Y
The table part 2 is controlled and the substrate to be inspected 5 is placed directly under the 111 part 3.
After setting the first fifl image plate 5b of b, in step 5T15, the imaging section 3 is made to image the substrate 5b to be inspected, and the R, G,
While the B color signal is subjected to Δ/D conversion in the Δ/D conversion section 23, the A/D conversion result (R, G, B color image data) is stored in the memory 24 in real time.

In this case as well, as in the teaching described above, the board to be inspected 5b is illuminated with white light and fluorescence is generated from the parts of the board to be inspected 5b other than the copper foil pattern 10, so that the information is stored in the memory 24. The signal level of the copper foil pattern 10 portion of the R color image data is low, and the signal level of the portion other than the copper foil pattern 10 in parentheses is high.

Next, the control unit 32 stores the memory 2 in step 5T16.
After transferring the R and GSB color image data stored in 4 to the image processing unit 26 and binarizing each pixel of the R color image data with a threshold value TH to avoid extracting a silhouette image of the copper foil pattern 10. , R in step 5T17
, G color image data are combined to create (RG) image data, and this (RG) image data is binarized to extract the characteristic parameters of the board mark 11.

Next, in step 5T18, the il control unit 32 creates a data file to be inspected based on each data processed by the image processing unit 26, and in step 5T19, it transfers this to the determination unit 22 and generates surface light determination data. It is compared with the file to determine whether the copper foil pattern 10 and the board mark 11 are correctly formed on the board 5b to be inspected.

After this, the control unit 32 performs steps 5T20 to 5T20.
Returning to T14, the above-described process is performed on the remaining area II.

Then, when the processing for all the image carrying areas is completed, the control unit 32 performs step 5T from step 5T20.
21, where the judgment results for each image carrier area are transferred to the CRT.
The information is supplied to the display 31 and printer 29 to display or print them out.

Thus, in this embodiment, each substrate 5a.

A daylight-excited fluorescent agent 8 is mixed into the substrate base 7 of 5b, and these substrates 5a are exposed to white light.

5b is illuminated to generate fluorescence from areas other than the area where the copper foil pattern 10 is formed.
A substrate 5a obtained by the imaging section 3.

By distinguishing between the fluorescent portion and the non-fluorescent portion of the R color signal of 5b, the copper foil pattern images of each of these substrates 5a and 5b can be easily extracted.

Furthermore, in this embodiment, since the color of each pixel is Ha based on the R, G color image data of the substrates 5a and 5b captured by the imaging unit 3, it is possible to check whether the substrate mark 11 is formed correctly. can also be inspected.

FIG. 5 is a block diagram showing another embodiment of the substrate inspection apparatus according to the present invention. In this figure, parts corresponding to those in FIG. 1 are given the same reference numerals.

The board inspection apparatus shown in this figure is different from the apparatus shown in FIG.
An R-phase filter 41a that transmits only light having the same hue as the fluorescence (R-phase) from the optical image of each substrate 5a, 5b obtained by the light distributor 40;
Substrates 5a and 5b obtained by filtering by a
A monochrome TV camera 42a converts the R-color optical image of the image into an electric signal, and from the optical image of each substrate 5a, 5b taken by the optical distributor 40, only light other than R phase, for example, G-phase light is transmitted. A G-phase filter 41b and a substrate 5 obtained by filtering with this G-phase filter 41b.
Monochrome T that converts the G color optical images of a and 5b into electrical signals
Each substrate 5a, 5b set on the X-Y table section 2 is imaged by an imaging section 3b equipped with a V camera 42b, and the R and G color signals thereof are supplied to the processing section 4. It is.

Even in this case, similarly to the above-mentioned embodiment, the imaging section 3b
By distinguishing between the fluorescent part and the non-fluorescent part of the R color signal of the substrates 5a and 5b obtained by
The shapes of the copper foil patterns 10 of a and 5b can be easily recognized, and thereby the copper foil pattern 1o formed on the substrate 5a and the copper foil pattern 1 formed on the substrate 5b can be easily recognized.
This allows easy comparison with o.

Also in this embodiment, R1 of each substrate 5a, 5b
Since the G color signal is 11, the board mark 11 on each board 5a, 5b can be recognized based on these R and G color signals.

Further, in each of the above-described embodiments, unmounted boards are to be inspected, but mounted boards may be to be inspected.

Furthermore, in each of the above-described embodiments, the color of each pixel is recognized based on the R and G color signals to extract the characteristic parameters of the board mark 11. It is also possible to extract the characteristic parameters of other printed marks and the like that have been formed and compare and inspect them.

(Effects of the Invention) As explained above, according to the present invention, even if the copper foil pattern is discolored or uneven, the copper foil pattern portion and other portions can be easily distinguished. As a result, the accuracy of determining whether the copper foil pattern is good or bad can be improved. In addition, it is possible to judge the quality of marks formed on the substrate.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of a board inspection apparatus according to the present invention, FIGS. figure(
△) is a partially enlarged plan view of the substrate in the same embodiment, FIG. 3(B) is a waveform diagram showing an example of the R color signal on line a of FIG. 3(A), and FIGS. 4(△) to (C) is a flowchart showing an operation example of the same embodiment, FIG. 5 is a block diagram showing another embodiment of the board inspection RM according to the present invention, and FIG.
Δ) to (F) are plan views showing examples of good and bad copper foil patterns, respectively. 1... Illumination section, 3... Imaging section, 4... Processing section, 5
a... Substrate (reference substrate), 5b... Substrate (substrate to be inspected), 7... Substrate base, 8... Daylight excited fluorescent agent,
10...Metal foil pattern (copper foil pattern). Agent Patent Attorney Tetsuji Iwao ((I!!1 person) 3rd
Figure 6

Claims (1)

[Claims] Board inspection that images a board that includes a board base and a metal foil pattern formed on the board base, and processes the resulting image to inspect the state of the metal foil pattern on the board. In the apparatus, an illumination unit that illuminates a substrate in which a daylight-excited fluorescent agent is mixed in advance in the substrate base;
an imaging unit that images the substrate illuminated by the illumination unit; and a metal plate formed on the substrate by recognizing a fluorescent portion and a non-fluorescent portion of an image obtained by the imaging unit; A board inspection device comprising: a processing section that inspects the condition of a foil pattern.