JPS63111404A - Inspecting method for substrate - Google Patents

Abstract

PURPOSE:To inspect the mounting state of parts on a substrate by coating the substrate to be inspected with preflux containing a daylight excited fluorescent agent, and then projecting visible homogeneous light and picking up an image. CONSTITUTION:An X-Y table part 14, a lighting part 12, an image pickup part 15, and a processing part 16 are provided and parameters (decision data) on respective parts 13a on a reference printed circuit board 10-1 which are obtained by picking up an image of the reference printed circuit board 10-1 are compared with parameters (data to be inspected) on respective parts 13b on the printed circuit board 10-2 to be inspected by picking up their image, thereby inspecting whether or not those respective parts 13 are mounted correctly. The printed circuit boards 10-1 and 10-2 are coated with the preflux containing the daylight excited fluorescent agent. Those printed circuit boards are picked up while irradiated with the visible homogeneous light and the light emission of a fluorescent layer 46 is decided by the processing part 16 to inspect the mounting state of the respective parts 13b.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for inspecting a board, which processes data obtained by imaging a board to inspect the state of component mounting on the board.

(Prior Art) When an automatic mounting device is used to mount various chip components such as resistors and semiconductor elements on a printed circuit board, the components may not be mounted according to the mounting data.

Therefore, when using such automatic mounting equipment, check the printed circuit board after mounting to ensure that the correct chip components are mounted in the correct position and orientation (position, direction) on the mounting board. Whether there is
It is also necessary to inspect whether or not it has fallen off.

However, if such an inspection is performed by manual visual inspection as in the past, there are problems in that the occurrence of inspection errors cannot be completely eliminated and inspection speed cannot be increased.

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

FIG. 10 is a block diagram showing an example of such an automatic inspection device.

The automatic inspection device shown in this figure includes a TV camera 3 that images the printed base 2-2 to be inspected on which the component 1 is mounted, and data input from the keyboard 8, that is, inspection standards as shown in FIG. Data regarding the type of the Narudon semi-printed M board 2-1, the type, arrangement position, mounting, posture, shape, etc. of each component 1 on this reference printed circuit board 2-1, and data regarding the posture, shape, etc. a storage unit 4 that stores information (data) regarding inspection processing procedures for the component 1;
The information stored in this storage unit 4 and the TV camera 3
It is determined whether all the parts 1 are present on the print board to be inspected 2-2 and whether these parts 1 are not misaligned or not by comparing the information shown by the image from A determination circuit 5 and a monitor 6 for displaying or printing out the determination results of this determination circuit 50.
It is composed of:

(Problem to be Solved by the Invention) By the way, some of the parts 1 inspected by this type of automatic inspection device have a color similar to the base color of the board, and for such parts 1, the signal level of the part The signal level of the background portion is almost the same, and there is a problem in that even if the component 1 has fallen off or is misaligned, it cannot be detected.

Therefore, on the base board of the printed circuit board 2-2 to be inspected,
As shown in FIGS. 12A and 12B, a resist 50 containing an ultraviolet-excited fluorescent agent is applied to form a resist W152, and when this is illuminated with an ultraviolet light source, the parts mounted on the base substrate 1 A device that can obtain a silhouette image of the part 1 has already been developed, but in such a device, the resist layer 52 is not formed on the land 51 as shown in FIG. The problem was that I couldn't get it.

In view of the above circumstances, the present invention makes it possible to obtain a complete silhouette image of a component, and thereby, even when the color of the component and the background color of the board are the same or similar, for all components,
To provide a board inspection method capable of inspecting whether these components have fallen off, misaligned, etc., and also inspecting whether the polarity of components and board marks are correct. It is an object.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the board inspection method according to the present invention involves taking an image of the board, processing the obtained data, and inspecting the component mounting state on the board. In a method for inspecting boards, after a preflux containing a daylight-excited fluorescent agent is applied, a decoy image is taken of the board on which components are mounted while illuminating it with visible monochromatic light, and the fluorescent parts of this original image are compared with the non-fluorescent parts. The present invention is characterized in that the mounting state of components on the board is inspected by distinguishing between parts.

(Embodiment) FIG. 1 is a block diagram showing an example of a substrate inspection apparatus to which a first embodiment of the substrate inspection method according to the present invention is applied.

The board inspection apparatus shown in this figure includes an X-Y table section 14, an illumination section 12, and! It is equipped with an Iυ image unit 15 and a processing unit 16, and each component 13 on the reference printed circuit board 10-1 obtained by R@ the reference printed circuit board 1 to the board 10-1.
a parameter (judgment data) and the printed circuit board 1 to be inspected obtained by taking a decoy image of the printed board 10-2 to be inspected.
The parameters (data to be inspected) of each component 13b on 0-2 are compared with each other to check whether each of these components 13b is correctly mounted.

In this case, the reference printed circuit board 10-1 is manufactured as described below.

First, a blank substrate 11 as shown in FIG. 2(A) is prepared by performing etching, resist processing, hole drilling, etc. on a raw substrate having copper foil covered on both sides (or one side). Next, a daylight-excited fluorescent agent (for example, F manufactured by Shinroihi Co., Ltd.
After forming a fluorescent layer 46 by applying a preflux 45 containing (Z-6013, FZ-6011, etc.), a portion of the fluorescent layer 46 where the component 13a is mounted is formed as shown in FIG. 2(B). , an adhesive 47 containing a daylight-excited fluorescent agent.
, or apply a solder paste 48 containing a daylight-excited fluorescent agent. As shown in FIG. 2(C), the reference printed circuit board 10- is mounted with the component 13a on top of it.
It becomes 1.

Further, the printed circuit board 10-2 to be inspected is also manufactured in the same procedure as the reference printed circuit board 10-1.

Further, the X-Y table section 14 includes each of the printed circuit boards 10
-1.10-2 is equipped with a 6X-Y table 19 and two pulse motors 17 and 18 that drive the X-Y table 19 based on control signals from the processing section 16, - Reference printed circuit board 1O-1 (or printed circuit board 1 to be inspected) set on Y table 19
O-2) is illuminated by the illumination unit 12 while the imaging unit 1
The image is taken by 5.

The illumination unit 12 includes a white light source 7 that is on/off controlled and dimmed based on a control signal from the processing unit 16, and a visible monochromatic light from the white light emitted by the white light source 7 (this visible monochromatic light is An excitation light selection filter 9 selectively transmits only the light having a wavelength that excites the daylight-excited fluorescent agent, and visible monochromatic light selected by the excitation light selection filter 9 is
Each printed circuit board 10-1 is reflected to the Y table section 14 side.
．． A half mirror that illuminates the printed circuit boards 10-2 and transmits light from each of the printed circuit boards 10-1 and 10-2.
20, and the light transmitted through this half mirror 20 is supplied to the l1fi image section 15.

The imaging section 15 includes a color TV camera 21 that is controlled by a control signal from the processing section 16, and each of the printed circuit boards 10-1 supplied via the front illumination section 12 by the color TV camera 21. The optical image of .10-2 is converted into electric signal@(RlG, B color signal@) and supplied to the processing section 16.

In this case, each printed circuit board 10-1 is
．． 10-2, each printed circuit board 10-1.1
Since the fluorescent W346 on 0-2 emits fluorescent light (for example, red light), the printed circuit board 10 as shown in FIG. 3(A)
- Each component 13a whose ground color is brown and which is mounted on each of these printed circuit boards 10-1 and 10-2.

Even when the color of 13b is brown or black, Fig. 3 (B), (
As shown in C), if we focus on the portion of the R, G, and B color signals output from the image section 15 that corresponds to the scanning line a of the R color signal, we can see that the signal level of the components 13a and 13b is higher than that of the background portion. signal level is higher.

Therefore, by simply binarizing this R color signal using the threshold value Tl-11, a silhouette image of each component 13a, 13b and the board mark area 55 (see FIG. 2(C)) can be obtained.

Furthermore, using this silhouette image, a G image (or 8 images) of the part 138.13b and a G image (or B111) of the part 138.
By using each image (J image) and converting it into 2fffi with a threshold value TH2, it is possible to identify the electrodes 83 of each component 13a and 13b to determine the polarity or read the value of the board mark.

The processing section 16 also includes an A/D conversion section 23, a computer 24, a teaching table 25, an image processing section 26, a determination section 22, an XY stage controller 27, an image transport controller 38, CRT display 28 and printer 2
1, a gee board 30, and a control unit (CPU) 31, and when in the feeding mode, the leaping unit 15
The characteristics of each component 13a and board mark area 55 on the reference printed circuit board 10-1 are determined by processing the R, G, and B color signals (RSG and B color signals of the reference printed circuit board 10-1) supplied from the reference printed circuit board 10-1. Extract the parameters and create a judgment data file, and when in inspection mode, the above!
The R, G, B color signals (R, 01B color signals of the printed circuit board 10-2 to be inspected) supplied from the image unit 15 are processed to detect each component on the printed circuit board 10-2 to be inspected. 13b and the characteristic parameters of the board mark area 55 are extracted to create a data file to be inspected.

Then, this inspected data file is compared with the judgment data file, and based on the comparison result, it is determined whether the board mark value of the inspected printed circuit board 10-2 and the polarity of each component 13b are correct, and whether or not these components are correct. 13b are all mounted without any positional deviation.

When the A/D converter 23 is supplied with the R, G, and B signals from the one-center image unit 15, the A/D converter 23 converts them into Δ/D (analog
(digital conversion) and then supplies this to the control section 31.

The memory 24 also includes I' (AM (Random Access Memory), etc., and is used as a work area for the control section 31.

Further, the image processing section 26 uses the R, G, and G signals via the υ control section 31.
, Bii! ii When the image data is supplied, this RlG
, 8 image data is binarized using a threshold value TH1 to create a silhouette image of each component 13a, 13b and the board mark 55, and the image signal (R
and G (or B)), each part 13a, 1
J3 is configured to identify or cover the polarity of J3 and the board mark of J3.The data obtained here is supplied to the control section 31 and determination section 22.

The teaching table 25 is equipped with a floppy disk device, etc., and when supplied with a judgment data file etc. from the control section 31 during teaching,
This is stored, and when the control section 31 outputs a transfer request during inspection, the judgment data file etc. is read out in response to this request and transferred to the control section 31 and the judgment section 2.
2 etc.

Further, the determination unit 22 is supplied with a determination data file from the control unit 31 at the time of examination, and the determination unit 22
When the inspection data file is transferred from 6, it is compared and determined whether the board mark of the printed circuit board 10-2 to be inspected, the polarity of the components 13b, etc. are correct, and whether all of these components 13b are correct without any positional deviation. It is configured to determine whether or not it is mounted, and the result of this determination is supplied to the control section 31.

The ia controller 38 also includes an interface for connecting the control section 31 with the illumination section 12 and the imaging section 15, and based on the output of the control section 31, the illumination section 12 and the imaging section 15.

Further, the X-Y stage controller 27 includes the control section 3
1 and the X-Y table section 14, and controls the X-Y table section 14 based on the output of the control section 31.

The CRT display 28 is equipped with a Braken tube (CRT), and receives image data from the control section 31, judgment results, and
When key human power data etc. are supplied, this is displayed on the screen.

Further, when the printer 29 is supplied with the determination result etc. from the control section 31, it prints it out in a predetermined format.

Further, the keyboard 30 is used to store operation information, data regarding the reference printed circuit board 10-1, and the like.
The keyboard 30 is equipped with various keys necessary for inputting data, etc. regarding the component 13a on the keyboard 30, and information, data, etc. input from the keyboard 30 are supplied to the control section 31.

The control section 31 includes a microprocessor and the like, and operates as described below.

First, when inspecting a new printed circuit board 10-2 to be inspected, the control unit 31 calls the teaching routine 32 of FIG. 4(B) in step ST1 of the main flowchart as shown in FIG. 4(A). In step ST2 of this routine 32, each part of the apparatus is controlled to turn on the illumination part 12 and the image movement part 15, and the image transport conditions and data processing conditions are set, and then in step ST3 the X-Y table part 1 is turned on.
It is checked whether the reference printed circuit board 10-1 is set on the board 4. 2 Then, place the standard printed circuit board 1 on the X-Y table section 14.
If 0-1 is set, the control section 31 proceeds to step ST3.
Then, the process branches to step ST4, where the X-Y table section 14 is controlled to position the %Q printed circuit board 10-1, and then the reference printed circuit board 10-1 is imaged by the imaging section 15, and this positive RSG obtained by image motion,
While the B color signal is A/D converted by the A/D converter 23, the Δ/D conversion result (R, G, 8 image data) is stored in the memory 24 in real time.

Next, the control unit 31 stores the memory 24 in step ST5.
The R, G, f3iiTii4/JA data stored in the image processing unit 26 is transferred to the image processing unit 26.
The above R, G, [Rj of the 3 image data! J image data is binarized using RFIT H1 to extract silhouette images of each component 13a and board mark area 55, and in step ST6, each component 13a and board mark area 55 is extracted from the R1G and B image data using this silhouette image. One pile of 0 images in the mark area 55 is displayed.

Next, the control unit 31 controls the image processing unit 26 in step ST7.
and control each component 13a and board mark area 5.
After dividing the 0 image of 5 into regions of each part (electrode, etc.),
The brightness of the three primary colors of each component is determined to identify the electrode polarity of each component 13a and the board mark of the reference printed circuit board 10-1.

After that, in step ST8, the control unit 31 creates a determination data file necessary for inspecting the printed circuit board 10-2 to be inspected based on the silhouette image and the identification result, and stores this on the teaching table 25. After storing, this teaching routine 32 is ended.

Further, when this teaching routine 32 is finished and the test mode is set, the control section 31 calls the test routine 34 shown in the flowchart of FIG. 4(C) in step ST9 of the main flowchart, In step 5T10, the date data of the day and the ID number (rA separate number) of the printed circuit board to be inspected 10-2 are read from the teaching table 25 and the keyboard 30, and the judgment data file is read from the teaching table 25 and sent to the judgment unit. 22.

Thereafter, the control unit 31, after setting image transport conditions and data processing conditions, checks whether the printed circuit board 10-2 to be inspected is set on the XY table unit 14 in step ST11.

If this is set, the control section 31 branches from step ST11 to step ST12, where X-Y
By controlling the table section 14, the printed circuit board 10-2 to be inspected
position. After that, the control unit 31 causes the image unit 15 to image the printed circuit board 10=1 to be inspected, and converts the R, G, and r3 signals obtained by this RAM operation into an A/D converter.
While performing A/D conversion in the converting section 23, this Δ/D conversion result (RlG, 8 image data) is stored in the memory 24 in real time.

Next, in step 5T13, the control section 31 reads R, G, 8 image data from the memory 24, supplies this to the image processing section 26, and processes the Rii! of this image data. J image data is normalized by 21 with a threshold Tl-11 to extract silhouette images of each component 13b and board mark area 55, and in step 5T14, each component is extracted from the R, G, 8 image data using this silhouette image. 13b and Gnffl of the board mark area 55.

Next, the control unit 31 controls the image processing unit 2 in step 5T15.
6, and the electrode polarity of each component 13b and the board mark of the printed circuit board 10-2 to be inspected are identified using each parameter obtained by the teaching of the 0 image.

Thereafter, the control unit 31 creates a data file to be inspected based on the silhouette image and the identification result in step 5T16, and then transfers the data file to be inspected to the determination unit 22 in step 5T17. The inspection data file and the judgment data file are each compared to determine whether all the components 13b on the printed circuit board 10-2 to be inspected are mounted without positional deviation, and whether the electrode polarity and board mark of each component 13b are correct. At step 5T18, the judgment results are supplied to the CR7 display 28 and printer 29 to be displayed or printed out.

As described above, in this embodiment, the preflux 45 containing the daylight-excited fluorescent agent was applied to the unmounted board before the component 13a (or component 13b) was mounted.
Even when the base color of the printed circuit board and the color of each component 13a, 13b are the same, it is possible to obtain accurate sill error t-e of each of these components 13a, 13b, and also to avoid positional deviation of each component 13b. , it is possible to significantly improve the inspection accuracy regarding falling off, etc.

Further, in this embodiment, each printed circuit board 10-1.
Illuminate 10-2 with visible monochromatic light! II L, at this time, the board mark area 55 t of each printed circuit board 10-2
j and each component 13a mounted on each of these printed circuit boards 10-1 and 10-2.

The reflected light from 13b is divided into two by the threshold flu T l-(2) to detect the board mark of each printed circuit board 10-1, 10-2 and the electrode polarity of each component 13a, 13b. Detects when the type of printed circuit board is wrong, the wrong component is mounted on each printed circuit board 10-L 10-2, or the mounting direction (for example, the direction of the electrode) is wrong. be able to.

FIG. 5 is a block diagram showing an example of a substrate inspection apparatus to which the second embodiment of the substrate inspection method according to the present invention is applied. 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 one shown in FIG.
- A light splitter 44 that divides the light from the light splitter 44 into two, and a fluorescence selection filter that extracts the fluorescence emitted by the print 1110-1.10-2 from one of the lights emitted from the light splitter 44. 49a, a monochrome TV camera 42a that converts the fluorescence image selected by the fluorescence selection filter 49a into an electrical signal, and an excitation light selection filter 9 in the illumination unit 12 that selects the other light emitted from the light distributor 44. reflected light transmission filter 49b that extracts light of the same wavelength as
and a monochrome TV camera 4 that converts the reflected light image selected by the reflected light transmission filter 49b into an electrical signal.
2b constitutes an imaging unit 15-2, and each monochrome T
Fluorescent images obtained by V cameras 42a and 42b,
The reflected light image is supplied to the processing unit 16 for processing.

Of course, in this case as well, each of these printed circuit boards 10-
1.10-2 is coated with preflux 45 containing a daylight-excited fluorescent agent to form a fluorescent layer 46, so that the base color of each printed circuit board 10-1, 10-2 and each component 13a,
Even if the color of parts 13a and 13b is similar,
Accurate silhouette images can be obtained.

In this case, each monochrome TV camera 42a.

These monochrome TV cameras 42a, 42b convert the images of different colors into electrical signals, respectively.
The electrode polarity of each component 13a, 13b, the board mark of each printed circuit board 10-1, 10-2, etc. can be identified by applying cotton drawing between each image obtained by the method to distinguish the color of each pixel. be able to.

FIG. 6 is a block diagram showing an example of a substrate inspection apparatus to which the third embodiment of the substrate inspection method according to the present invention is applied. 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 one shown in FIG.
1. A fluorescence selection filter 61a for extracting a fluorescence image from the optical image of 10-2, and each of the printed circuit boards 10-1.1.
A reflected light selection filter 61b that extracts a reflected light image from the optical image of 0-2, and a drive circuit 59 that arranges either the fluorescence selection filter 61a or the reflected light selection filter 61b in front of the lens of the monochrome TV camera 60.
An imaging unit 15-3 is configured by the above, and a fluorescence image of each printed circuit board 10-1, 10-2 is obtained from an optical image of each printed circuit board 10-1, 10-2 supplied via the illumination unit 12, The reflected light images are sequentially extracted and converted into electrical signals,
These are sequentially supplied to the processing section 16 for processing.

Of course, in this case as well, each of these printed circuit boards 10-
1. Since preflux 45 containing a daylight-excited fluorescent agent is applied on 10-2, each printed circuit board 10-1
．． Even if the ground color of 10-2 and the color of each part 13a, 13b are similar, it is possible to accurately image each part 13a, 13b to Silera 1, and use this silhouette image. Color images obtained by the monochrome TV camera 60! By performing calculations between E4 (same color as fluorescence) and the reflected light color image to determine the color of each pixel, the polarity of the electrodes of each component 13a, 13b and each printed circuit board 10-1, 10-2 are determined. board marks etc. can be identified.

FIG. 7 is a block diagram showing an example of a substrate inspection apparatus to which the fourth embodiment of the substrate inspection method according to the present invention is applied. 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 one shown in FIG. The printed circuit boards 10-1 and 10-2 are placed on top of the board, and images are taken by the imaging unit 15-4 while being transported.

In this case, the day image section 15-4 includes a light distributor 58 that divides the optical image from the printed circuit board 10-1 and 10-2 supplied through the illumination section 12 into two;
From one optical image emitted from each printed circuit board 10
-1. A fluorescence selection filter 668 that extracts the fluorescence image of 10-2, a licensor 67a that converts the fluorescence image extracted by the fluorescence selection filter 66a into an electrical signal, and a It includes a reflected light selection filter 66b that extracts the reflected light image from the optical image, and a line sensor 67b that converts the reflected light image extracted by the reflected light selection filter 66b into an electrical signal, and each line sensor 67a, 67b successively captures images of each printed circuit board 10-1.
The fluorescence image of 10-2 and the reflected light image are processed by a processing unit 16-4.
supply and process it.

Of course, in this case as well, each of these printed circuit boards 10-
1. Since preflux 45 containing a daylight-excited fluorescent agent is applied on 10-2, each printed circuit board 10-1
．． Even when the ground color of 10-2 and the color of each component 13a, 13b are similar, an accurate silhouette image of each component 13a, 13b can be obtained, and this silhouette image and line sensor G7a, 67b and the reflected light image to determine the color of each pixel, each component 13a.

13b electrode polarity, each printed circuit board 10-1.10
-2 board mark etc. can be identified.

FIG. 8 is a block diagram showing an example of a board inspection apparatus to which the fifth embodiment of the board inspection method according to the present invention is applied. In this figure, parts corresponding to those in FIG. 1 are given the same reference numerals.

The board inspection device shown in this figure is different from the one shown in FIG.
Visible monochromatic beam light source 7 equipped with an optical system for photographing in the direction
While spot illuminating the printed circuit boards 10-1 and 10-2 set in the X-Y lap section 14 by the imager section 15-5, each of the printed circuit boards 10-1.1
The light from 0-2 is converted into an electrical signal.

In this case, the phantom part 15-5 is connected to the printed circuit board 10-
1. A light splitter 71 that divides the light from 10-2 into two,
A fluorescence selection filter 72a extracts fluorescence emitted from each printed circuit board 10-1, 10-2 from one of the lights emitted from the light distributor 71, and converts the fluorescence selected by the fluorescence selection filter 72a into an electrical signal. A phototransistor (or photomultiplier tube, photodiode, etc.) 73a that outputs light of the same wavelength as the beam light emitted by the visible monochromatic beam light source 70 from the other light emitted from the light splitter 71. It includes a reflected light selection filter 72b to extract, and a phototransistor (or photomultiplier tube, photodiode, etc.) 73b to convert the reflected light selected by the reflected light selection filter 72b into an electrical signal. Transistor 73a
.

73b converts the light from the printed circuit boards 10-1. ) A pixel signal representing an image is supplied to the processing unit 16 for processing.

Of course, in this case, each of these printed circuit boards 10-
1. Preflux 45 containing a daylight-excited fluorescent agent is applied on 10-2, so the background color of the printed circuit board and
Even when the parts 13a and 13b are similar in color, accurate silhouette images of the parts 13a and 13b can be obtained, and this silhouette image and the fluorescence obtained by the phototransistors 73a and 73b can be By performing calculations between the pixel signal of the image and the pixel signal of the reflected light image to determine the color of each pixel, each part 13a, 131
), the board marks of each printed circuit board 10-1, 10-2, etc. can be identified.

FIG. 9 is a block diagram showing an example of a substrate inspection apparatus to which the sixth embodiment of the substrate inspection method according to the present invention is applied.

In this figure, parts corresponding to those in FIG. 1 are given the same reference numerals.

The board inspection device shown in this figure is different from the one shown in FIG. Pudding 1- Lt plate 10-1.10
1111 section 15-6 converts the light from each of these printed circuit boards 10-1 and 10-2 into electrical signals while spot illuminating the printed circuit boards 10-1 and 10-2.

In this case, the ratio imager 15-6 includes a phototransistor (or photomultiplier tube) 80 and each of the printers 1 to substrate 1.
a fluorescence selection filter 81a for extracting fluorescence from light from 0-1.10-2; and each printed circuit board 10-1.10.
- a reflected light selection filter 81b for extracting reflected light from light from the light source 2; and a drive circuit 82 for disposing either one of the fluorescence selection filter 81a and the reflected light selection filter 81b in front of the lens of the phototransistor 80. The fluorescence selection filter 81a and the reflected light selection filter 81b are sequentially used to
The light from 2 is converted into an electric signal by the phototransistor 80, and each printed circuit board 10-1.1 obtained thereby
A pixel signal indicating the fluorescence image of 0-2 and a pixel signal indicating the reflection image are supplied to the processing unit 16 for processing.

Of course, in this case as well, each of these printed circuit boards 10-
1. Preflux 45 containing a daylight-excited fluorescent agent is applied on 10-2, so the background color of the printed circuit board and
Even when the parts 13a and 13b are similar in color, accurate silhouette images of the parts 13a and 13b can be obtained, and this silhouette image and the pixel signals of the fluorescent image obtained by the phototransistor 80 can be , and the pixel signal of the reflected light image to determine the color of each pixel, the polarity of the electrodes of each component 13a, 13b, the board mark of each printed circuit board 10-1, 10-2, etc. can be identified.

(Effects of the Invention) As explained above, according to the present invention, it is possible to obtain a complete silhouette image of a component, and it is possible to obtain a complete silhouette image of a component. Even in the case of a computer, all parts can be inspected to see if they have fallen off or misaligned, and it can also be inspected to see if the polarity of the parts and board marks are correct.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the first embodiment of the present invention, FIGS. Δ) is a plan view showing an example of parts in this first embodiment, and FIG.
) and (C) are waveform diagrams each showing an example of the carrier signal on line a in FIG. FIG. 5 is a block diagram showing a second embodiment of the invention, FIG. 6 is a block diagram showing a third embodiment of the invention, FIG. 7 is a block diagram showing a fourth embodiment of the invention, and FIG. 8 is a block diagram showing a fourth embodiment of the invention. The figure is a block diagram showing a fifth embodiment of the present invention, FIG. 9 is a block diagram showing a sixth embodiment of the present invention, FIG. 10 is a block diagram showing an example of conventional automatic inspection purchasing, and FIG. 11 is a block diagram showing a sixth embodiment of the present invention. is a front view showing an example of a reference printed circuit board used in this device, FIG. 12(A), (r3
) are printed circuit board manufacturing process diagrams for explaining other examples of conventional automatic inspection equipment, and FIG. 13 is a partially enlarged plan view of FIG. 12(B). 10-1... Reference printed circuit board, 1, 0-2... Printed circuit board to be inspected, 12... Lighting part, 14... X-
Y table unit, 15...imaging unit, 16...processing unit,
46... Fluorescent layer. Agent Patent attorney Iwa 012 (1 other person) Figure 3

Claims (1)

[Claims] In a board inspection method that processes data obtained by imaging a board to inspect the component mounting state on the board, the board on which the components are mounted is coated with a preflux containing a daylight-excited fluorescent agent. 1. A method for inspecting a board, comprising: taking an image while illuminating it with visible monochromatic light, and distinguishing between a fluorescent part and a non-fluorescent part of the imaging result to inspect a component mounting state on the board.