JPS6390707A - Inspection device for mounted substrate - Google Patents

Abstract

PURPOSE:To preclude misdecision making due to an error in the working of a substrate by extracting the position relation between parts on a packaged substrate and a land based on the land shape of an unpackaged substrate obtained a land extraction part and the land shape of the mounted substrate, and deciding the mounting states of the parts from the obtained position relation. CONSTITUTION:This device is equipped the an X-Y table part 20, a lighting part 21, an image pickup part 22, and a processing parts 23 and calculates the area (wider than a land 28b obtained by picking up the image of the unpackaged substrate 25) where a land can be present from the land 28b. This area where the land can be present is used to segment the part where a land 28c is present from the picked-up image of the mounted substrate 26 to be inspected and the land 28c at the segmented part is extracted. Then, the shapes of the lands 28b and 28c are compared with each other to find the part 28c hidden by a parts 27c on the packaged substrate 26 to be inspected and the position relation between the land 28c and parts 27c is found from information on the hidden part to decide whether or not the parts 27c is mounted correctly.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a mounting board inspection device for inspecting whether components are correctly mounted on a mounting board.

(Prior Art) As a mounted board inspection device for inspecting a mounted board created using a mounter or the like, the one shown in FIG. 12 is conventionally known.

The mounted board inspection apparatus shown in this figure includes a TV camera 3 that takes lff11g+ a printed board to be inspected 2b on which a component 1a is mounted and a reference printed board 2a that serves as an inspection reference, and the reference printed board obtained by this TV camera 3. 2
A storage unit 4 that stores an image (reference image) of a, and the reference image stored in this storage unit 4 and the image of the printed circuit board 2b to be inspected (image to be inspected) supplied from the TV camera 3. A determination circuit 5 compares and determines whether all the components 1b are present on the printed circuit board 2b to be inspected and whether or not these components 1b are misaligned, and the determination results of the determination circuit 5 are It is configured to include a display device 6 for displaying information.

(Problems to be Solved by the Invention) By the way, such a conventional mounted board inspection device simply determines the position of the component 1a on the reference mounted board 2a and the position of the component 1b on the printed circuit board 2b to be inspected. If these positions deviate from each other, it is determined that the mount is defective, so as shown in FIG. component position indicated by component 1a on reference mounting board 2a)
When it deviates from the position, it is determined that the mounting is defective even if the electrode and land of this component 1b are within a range where they can be electrically connected.

Therefore, it may be possible to determine an allowable range (tolerable range) 8 based on the normal position of the component 1b, and if it falls within this allowable range 8, it is determined that it is mounted normally. , in this case, each of these mounting boards 2a
, for each component mounted on 2b,
If the permissible range 8 is set individually, just inputting data regarding the permissible range 8 requires a great deal of time and effort.

In addition, in such a mounting board, even if the same pattern mask is used, the pattern formed on the board is slightly different for each board.
Even if the land 9 is placed correctly, if this land 9 is different from the land position of the reference mounting board 2a, that is, as shown in FIG. and the mounting board 2b to be inspected.
Land position 9b, component position 1 obtained by 111i image of
0b, even if the component position aiob is in a correct relationship with respect to the land position 9b, it will be determined that the component 1b is mounted poorly.

In view of the above-mentioned problems, the present invention is capable of automatically setting the optimum positional deviation tolerance for each component, and
Even if the land of the board to be inspected differs from board to board, if the component is mounted within an allowable range on the land, it can be determined that the mounting is good, and this will prevent errors caused by processing errors of the board. It is an object of the present invention to provide a mounted board inspection apparatus that can prevent judgments and can also determine the shape of a portion hidden by a component formed on a mounted board to be inspected.

(Means for Solving the Problems) In order to solve the above problems, a mounted board inspection apparatus according to the present invention includes a land extraction unit that extracts lands from an unmounted board image and a mounted board image obtained by an imaging unit. and,
A positional relationship extraction unit extracts the positional relationship between the components and lands on the mounted board based on the land shape of the unmounted board and the land shape of the mounted board obtained by the land extraction unit; The present invention is characterized by comprising a determining section that determines the mounted state of the component from the obtained positional relationship.

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

The mounted board inspection device, which is not shown in this figure, has an X-Y table section 2.
0, an illumination section 21, an image carrying section 22, and a processing section 23, and as shown in FIG. Determine the area where it can exist (this area is wider than the land 28b), and
Using this area where the land 28c exists, the area where the land 28c exists is cut out from the image obtained by transporting the mounting board 26 to be inspected as shown in FIG. A certain land 28c is extracted. Then, by comparing the shapes of these lands 28b and 28c, the portion of the land 28G on the mounting board 26 to be inspected that is hidden by the component 27c is determined, and from the information on this hidden portion, the land 28c and the component 27C are determined. It is determined whether this part 27c is correctly mounted.

The illumination unit 21 includes a ring-shaped white light 11119 that is controlled on/off (or dimming control I) based on the control signal from the processing unit 23, and receives the illumination on signal from the processing unit 23. When supplied, it is turned on and illuminates the upper surface side of the XY table section 20 until an illumination off signal is supplied from the processing section 23.

The X-Y table section 20 includes pulse motors 31a and 31b that operate based on control information from the processing section 23;
An X-Y table 32 is driven in the X-axis direction and the Y-axis direction by each of these pulse motors 31a and 31b, and each board 24 to 26 is provided on this X-Y table 32. When the substrates 24 to 24 are placed on the substrates 24 to
26 on the X-Y table 32
3, each of the substrates 24 to 26 fixed by the chuck mechanism 33 is imaged by the imaging unit 22 while being illuminated by the illumination unit 21.

The image carrying section 22 includes a color TV camera 34 provided above the illumination section 21, and the image carrying section 22 includes a color TV camera 34 provided above the illumination section 21.
The optical image is converted into an electrical image (R, G, B color signals) by this h-color TV camera 34 and supplied to the processing section 23.

The processing section 23 includes an A/D conversion section 36, a memory 37, a teaching table 38, three image processing sections, and an X-Y
Stage controller 41, image carrier controller 42, CR7 display 43, printer 44, and keyboard 4
5 and a control unit (CPU) 46, during teaching, processes the R, G, and B color signals of each substrate 24.25 supplied from the Wi image unit 22, and outputs the actual image to be inspected. An inspection data file for inspecting the WIA board 26 is created. At the time of inspection, the R, G, and 8-color signals of the mounted board 26 to be inspected supplied from the image carrier 22 are processed based on the inspection data file, and the signals formed on the mounted board 26 to be inspected are processed. land 2
It is determined whether the relative position between 8C and the component 27c is within an allowable range, and the result of this determination is displayed.

When the A/D conversion unit 36 is supplied with the image signal (R, G, B color signal) from the 1lii (61 unit 22),
This is A/D converted (analog/digital conversion) to create color image data, which is then converted to t, II 111 Part 4
Supply to 6.

Furthermore, the memory 37 includes a RAM (random access memory) and the like, and is used as a work area for the control section 46.

Furthermore, when the three image processing units are supplied with image data via the control unit 46, the three image processing units binarize this image data to extract position and shape data of parts, and extract necessary images from the image data. You can cut out the image, perform hue/brightness conversion on this cut out image, predetermine the result of this hue/brightness conversion,
The position of the land pattern,
It is configured to extract shapes, etc., and each data obtained here is supplied to the control section 46.

Furthermore, the teaching table 38 is equipped with a floppy disk device, etc., and when it is supplied with an inspection data file etc. from the control section 46, it stores it, and when a transfer request is output from the control section 46, it stores this request. The inspection data file and the like are read out in accordance with the above, and are supplied to the control section 46.

The image carrier controller 42 includes an interface connecting the control section 46 and the illumination section 21 and the imaging section 22, and controls the illumination section 21 and the image pickup section 22 based on the output of the control section 46. control.

Further, the X-Y stage controller 41 has the υ1t1
1 section 46 and the X-Y table section 20, and the X-Y table section 20 is controlled based on the output of the control section 46.
do.

The CR7 display 43 is equipped with a cathode ray tube (CRT), etc., and receives image data, judgment results, etc. from the control section 46.
When key human power data etc. are supplied, this is displayed on the screen.

Further, when the printer 44 is supplied with the determination results etc. from the control section 46, it prints out the results in a predetermined format.

The keyboard 45 also includes various keys necessary for inputting operation information, data regarding the name of the board 26 to be inspected, board size, etc., data regarding the component 27c on the board 26 to be inspected, etc. Information, data, etc. input from this keyboard 45 are supplied to a control section 46.

The Hil control section 46 includes a microprocessor and the like, and operates as described below.

First, when inspecting a new mounting board 26 to be inspected,
The control unit 46 displays a message requesting the board name (for example, board identification number) and board size on the CR7 display 43 in step ST1 of the teaching flowchart shown in FIG.

When the board name and board size are input from the keyboard 45, the control unit 46 paints a teaching board (parts are painted white and other parts are painted black) on the X-Y tail 32 in step ST2. mounted board) 2
Hold until 4 is placed. After this, when the substrate 24 is placed, the control section 46 controls the X-Y table section 20 to move the first image carrying area of the substrate 24 below the color TV camera 34.

Next, the control section 46 causes the A/D conversion section 36 to A/D convert the image signal obtained by the color TV camera 34, and stores this A'/D conversion result (image data of the board 24) in the memory 37 in real time. Let me remember it.

Next, the control section 46 sequentially reads out the R pixels (or G, B pixels) of the image data stored in the memory 37, binarizes them in the image processing section 39, and paints the substrate 24 white. After extracting the part (part 27a), each part 27a obtained by this extraction operation is
position data and shape data are stored in the teaching table 38.

Thereafter, the control unit 46 displays the position and shape screen 29 of the component 27a as shown in FIG. 3 based on the position data and shape data of each component 27a stored in the teaching table 38 in step ST3. Create and CR this
7 on the display 43, and also displays a message requesting manual input from the keyboard 45 for special parts.

Here, if the operator inputs the position data and shape data of the special part, the position data and shape data of the special part stored in the teaching table 38 are corrected accordingly. .

Next, the control unit 46 switches the CR7 display 4 in step ST4.
3 displays a message requesting input of the type and direction of each part 27a, and if the type and direction of each part 27a are input, the shape, type, and direction of each part 27a is displayed. The area where the land should exist (land extraction area) is determined according to the above.

In this case, if the component 27a is a three-electrode component such as a transistor, each electrode 47 of the component 27a as shown in FIG.
A land extraction area 1d 48 a is obtained that extends outside of this component 27a so as to include the component 27a, and if the component 27a is a two-electrode component such as a resistor, the component 27a as shown in FIG. A land extraction region 488 is required that includes the electrodes 47a formed at both ends of the component 27a and extends outside the component 27a.

Next, the control unit 46 expands each of these land extraction areas 48b as shown in FIGS.

After this, the remaining parts 27a in this first removal area
The above-described processing is also performed for .

Then, when the creation operation of the land extraction area 49a is completed for all the parts 27a in the i'eia area, the control unit 46 goes to step ST5 to
Returning to T2, the above-described process is repeatedly executed for the remaining image transport areas, and when land extraction areas 49a are obtained for the parts 27 in all image transport areas, step ST5
The process branches to step ST6.

Then, in this step ST6, the control section 46:
Wait until the teaching board 24 is removed from the XY table section 20 and the unmounted board 25 is placed on it.

Next, an unmounted board 25 is placed on this X-Y table section 20.
is set, the control section 46 controls the X-Y table section 20
control the unmounted board 2 below the color TV camera 34.
5. Locate the first hired killer area.

After that, the control unit 46 performs A/D conversion on the image signal obtained by the color TV camera 34, and also performs A/D conversion on the image signal obtained by the color TV camera 34.
D conversion result! ! ! (image data of the unmounted board 25) is stored in the memory 37 in real time.

Next, the control unit 46 reads out the enlarged land extraction area 49a from the teaching table 38, supplies it to the image processing unit 39, and performs image processing on the image data of the unmounted board 25 stored in the memory 37. Part 3
9 to extract a land from this image data.
The image a (the image within the land extraction area 49a) is cut out.

Next, the control unit 46 supplies hue and brightness conversion commands to the three image processing units to avoid hue and brightness conversion of each pixel constituting the image within the land extraction area.

As a hue-lightness conversion formula in this case, for example, the following formula is used.

B RT (ij)= R (ij)+ G (ij)+
B (ij)...(1) Rc (ij)= a −
R(ij)/B R King C13)-(2)Gc(ij
)=a −G(ij)/B RT(ij)・(3)B
e(ij)=a-B(ij)/B RT(ij)・(
4) However, in this case, R(ij): R signal strength of the pixel (pixel (ij)) in the i-th row and j-th column G(ij): the pixel (pixel (im)) in the i-th row and j-th column G signal strength B (ij): B signal strength B RT (ij) of the pixel in the i-th row and j-th column (pixel (ij)): brightness α of the pixel (ij): coefficient Rc (ij): The red phase G c (i
j): Green hue of pixel (ij) B c (ij): Portrait hue of pixel (ij) And the land extraction area 498
When the hue-lightness conversion described above is completed for all pixels in the land extraction area 49a, the control unit 46 converts each pixel (1
It is checked whether the red hue RC(ij) for j1 is equal to or greater than a pre-input land extraction reference value C (for example, C=0.4·α), and the land 28b within the land extraction area 49a is extracted.

The control unit 46 stores the position data and shape data regarding the land 28b in the teaching table 38, calculates the distance between the lands for each part 27a, and uses this calculation result (distance data) for teaching. It is stored in table 38.

In this case, each of these distance data is used for each part 2 on the mounter.
It is used as data to teach the tolerance of 7 and to evaluate the design of the land pattern.

Next, the control unit 46 expands the shape data of the land 28b as shown in FIGS.
I remember it.

After that, the control unit 46 controls the land 2 in step ST8.
Based on the position and shape of the part 8b, as shown in FIGS. 8(A) and 8(B), a part body inspection area 51b for cutting out the fire part in each part 27a is calculated, and this is placed on the teaching table 38. At the same time, a message requesting characteristic data (for example, color data) regarding the body of each component 27a is displayed on the CR7 display 43.

Then, the operator operates the keyboard 45 to select all parts 2.
When the characteristic data 7a is input, the control unit 46 stores it in the teaching table 38.

After this, the remaining parts 27a in this first imaging area
The above-mentioned operation is repeated for .

When the land extraction process and the feature data input process are completed for all of the parts 27a in the first imaging area, the control unit 46 returns to step ST6 via step ST9, and processes the remaining image carrying area. Then, the above-described process is repeatedly executed.

Thereafter, when the above-described processing is completed for all the parts 27a in the flu area, the control unit 46 performs step ST9.
The process branches to step 5T10.

In step 5T10, the control unit 46 organizes each data stored in the teaching table 38 to create an inspection data file, stores this in the teaching table 38, and ends the teaching operation.

Further, when this teaching operation is completed and the inspection mode is set, the control unit 46 requests the board name of the mounted board 26 to be inspected on the CR1 display 43 in step 5T11 of the inspection flowchart shown in FIG. 2(B). display the message to be sent.

Then, if this board name is input from the keyboard 45, the control unit 46 controls the X-Y table 3 in step 5T12.
2 until the mounting board 26 to be inspected is placed on it. After this, when this mounting board 26 to be inspected is mounted, the control unit 46
The X-Y table section 20 is fl, IJa and the color TV is
A first image carrying area of the inspected mounting board 26 is arranged below the camera 34.

Next, the control unit 46 causes the A/D conversion unit 36 to A/D convert the image signal obtained by the color TV camera 34, and stores the A/D conversion result (image data of the mounted board 26 to be inspected) in the memory 37. be stored in real time.

Next, the control unit 46 reads out the component body inspection area 51b from the teaching table 38 and supplies it to the image processing unit 39, and also sends the image data of the board to be inspected 26 stored in the memory 37 to the image processing unit. 39
and cuts out an image of the inspection area 51b from this image data.

Next, the control H146 supplies a feature extraction command to the image processing unit 39 to extract feature data of the image cut out by the inspection area 51b (for example, to convert each pixel of the image into hue and brightness).

Thereafter, in step 5T13, the control unit 46 determines whether the feature data of the image within the inspection area Ta51b matches the feature data of each component 27a stored in the teaching table 38, and if these If they match, step 5T13 to step 5T14
The land inspection area 50b is read out from the teaching table 38 and is supplied to the image processing unit 39, and the image data of the board to be inspected 26 stored in the memory 37 is sent to the image processing unit 39. An image of the land inspection area 50b is cut out from this image data.

Next, the control section 46 supplies the image processing section 39 with a hue/brightness conversion command to convert the land inspection area 1i'! 50
Each pixel constituting the image b is subjected to hue and brightness conversion.

Then, when the above-described hue-lightness conversion is completed for all pixels in the land inspection area 50b, the III 00 unit 46 converts the red hue RC(i, i ) is entered in advance as the land extraction Hty value C (for example, C=0.4・α
) or more, and check whether the land inspection area 50b is greater than or equal to
Extract the land 28c inside.

After that, the control unit 46 checks whether B RT (ij) for each pixel (ij) in the land inspection area 50b is greater than or equal to a pre-input electrode extraction reference value, and Extract 8i47c.

Next, in step 5T16, the i, 1ltll1 unit 46 determines the shape of the land 28c and the unmounted board 25 stored in the teaching table 38 while referring to the position and shape of the electrode 47c in the land inspection area 50k).
The shape of the land 28b is compared with the shape of the land 28b to eject (estimate) the portion of the land 28C that is hidden by the component 27c.

Thereafter, in step ST17, the i, 1JfO unit 46 uses the extracted results to obtain overlapping area data (parts of land 28C) indicating the positional relationship between these lands 28c and parts 27c, as shown in FIGS. 9(A) and 9(B). The area data (area data), width data, and depth data of the portion covered by 2A C are determined, and it is checked whether the values of each of these data are sufficient.

If these eight values are sufficient, the control unit 46 branches from step 5T17 to step 5TI8, where it determines that this component 27c is properly mounted and displays it on the CR1 display 43. , or print it out using the printer 44.

Further, in each step 5T13.5T17, it is determined that the feature data of the image within the inspection area 51b does not match the feature data of each component 27a stored in the teaching table 38, or the land 28G and the component 27c If it is determined that the cover area data, width data, and depth data indicating the positional relationship with It is determined that it is defective, and this is displayed on the CRT display 43 or printed out from the printer 44.

After this, the remaining parts 27G in this first decoy image area
, the above-described process is repeated, and when the determination process is completed for all parts 27C, the control unit 46 returns to step 5T12 via step 5T20, and performs the above-described process for the remaining imaging areas. Execute repeatedly. .

Then, once the determination process has been completed for the parts 27G in all the imaging areas, this inspection process is ended.

As described above, in this embodiment, the mounting board to be inspected 26
Even if the land 28C is different for each board, the land 28C
If the component 27C is mounted within the allowable range on c, it can be determined that the mounting is good, so it is possible to prevent erroneous determination due to processing errors of the board, and also to The optimal misalignment tolerance can be automatically set.

As a result, in the cases shown in Figures 10 (A), (B) and 11 (A), (B), it is determined that the mount is good, and in the cases shown in Figures 10 (C) and 11. Figure (C), (
In the case shown in D), it can be determined that the mounting is defective.

Furthermore, in the embodiment described above, during teaching,
I am trying to input the type of part 27a manually, but
The component 27a is selected from an image input using a reference mounting board, etc.
Alternatively, the type of the component 27a may be automatically input based on the electrode position 4 detected.

Furthermore, in the embodiment described above, during teaching,
Although the feature data of the component 27a is manually input, it may also be automatically input using a reference mounting board or the like.

(Effects of the Invention) As explained above, according to the present invention, each part has R
It is possible to automatically set an appropriate positional deviation tolerance, and even if the land of the board to be inspected differs from board to board, as long as the component is mounted within the allowable range on the land, the mounting will be successful. This makes it possible to prevent erroneous judgments due to processing errors of the board, and also to know the shape of a portion hidden by a component formed on the board to be inspected.

[Brief explanation of the drawing]

FIG. 1(A) is a block diagram showing an embodiment of a mounted board inspection apparatus according to the present invention, FIG. 1(B) is a diagram schematically showing the transfer result of an unmounted board in the above embodiment, and FIG. Figure (C
) is a diagram schematically showing the transfer result of the inspected mounting board at the length tMPA, FIG. 2(A) is a flowchart showing an example of the teaching operation of the same embodiment, and FIG. 2(B)
3 is a flowchart showing an example of the inspection operation of the same embodiment, FIG. 3 is a schematic diagram showing an example of a part position and shape screen of the same embodiment, and FIG. 4 is an example of a land extraction area for a transistor etc. of the same embodiment. FIG. 5 is a schematic diagram showing an example of a land extraction area for resistance etc. in the same embodiment, and FIG.
A) and (B) are schematic diagrams each showing an example of an enlarged land extraction area for each component of the same embodiment, and FIG.
(8) is a schematic diagram showing an example of the land inspection area for each component of the same embodiment, and FIGS. 8(A) and (B) are schematic diagrams each showing an example of the component body inspection area for each component of the same embodiment. 9(A) and 9(B) are schematic diagrams for explaining the judgment operation regarding the positional relationship between the parts and the land in the same embodiment, and FIGS. 10(A) to 10(C) are the same. Schematic diagram for explaining the determination example of the example, FIG. 11 (A) ~
(D) is a schematic diagram for explaining the determination example of the same embodiment, FIG. 12 is a block diagram showing an example of a conventional mounted board inspection device, and FIG. 13 is for explaining mounting misalignment in this mounted board inspection device. FIG. 14 is a schematic diagram showing the positional relationship between lands and components in this mounted board inspection apparatus. 22... Layer image portion, 25... Unmounted board, 26...
Mounting board, 27C...Component, 28b, 28C...Land, 39...Land extraction section (image processing section), 46.
...Positional relationship extraction unit 1 determination unit (control unit). Agent: Patent attorney Iwa 012 (and 1 other person), 1st CB
) Figure 9 (A) Figure 9 [8] t! +

Claims (1)

[Claims] A land extractor extracts lands from the unmounted board image and the mounted board image obtained by the imaging unit, and the land shape of the unmounted board and the land shape of the mounted board obtained by the land extractor. a positional relationship extraction unit that extracts the positional relationship between the component and the land on the mounting board based on the positional relationship extraction unit; and a determination unit that determines the mounted state of the component from the positional relationship obtained by the positional relationship extraction unit. A mounted board inspection device characterized by: