JPH10307007A - Apparatus and method for inspection of substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an apparatus and a method in which the inspection time of a substrate is shortened by a method wherein the position of a light source on one side out of one pair of upper and lower light sources is adjusted and the range of image data used to find the difference between image data by the pair of upper and lower light sources is regulated by an inspection frame. SOLUTION: First, in a teaching mode, luminances of one pair of upper and lower sources 1, 2, the position of the lower light source 2, an inspection frame and a reference value as a threshold value are set in advance for every substrate 10 in such a way that the difference between a nondestructive substrate 10 and a defective substrate 10 becomes clear. In an inspection mode, the light sources 1, 2 and a CCD camera 81 are moved to a part just above the substrate 10, the lower light source 2 is turned on at a preset luminance, and the lower light source 2 is positioned. At this time, the upper light source 1 is turned off. The CCD camera 81 fetches an image. Then, the upper light source 1 is turned on at a luminance, the lower light source 2 is turned off, and the CCD camera 81 fetches an image. The difference between the respective images inside the inspection frame is found, and whether the substrate 10 is good or not is judged. Since the range of image data is regulated by the inspection frame, the total inspection time of the substrate 10 can be shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a board inspection apparatus which adjusts the distance and illuminance between a pair of light sources for each board to be inspected, performs image processing only within a set inspection frame, and enables high-speed processing. Related to inspection method.

[0002]

2. Description of the Related Art Conventional substrate inspection apparatus and inspection method (JP-A-4-329344 and JP-A-5-52534).
A pair of upper and lower two light sources are used as a lower light source and an upper light source, an image captured by a CCD camera when only the lower light source is turned on is set as an image 1, and when only the upper light source is turned on, C
By taking the image captured by the CD camera as image 2 and taking the difference between image 1 and image 2, image processing is performed on the obtained image and board inspection is performed.

[0003]

In the above-described conventional board inspection apparatus and method, the leads of the components provided on the board to be inspected have different widths and thicknesses for each board to be inspected, There is a problem that the difference between a non-defective product and a defective product cannot be clearly obtained when the angle and the illuminance of the light source are constant because the attachment state is slightly different.

In addition, the conventional board inspection apparatus and method also process image data in a portion other than the area required for the inspection. Therefore, it takes a long processing time to obtain a difference between images, and the entire inspection time becomes long. There was a problem.

The inventor of the present invention drives a pair of upper and lower light sources disposed at intervals to irradiate light on the surface of the substrate at different timings, adjusts a relative positional relationship between the pair of upper and lower light sources, A book for imaging the surface of a substrate illuminated by the pair of upper and lower light sources whose relative positional relationship has been adjusted, and judging pass / fail based on a difference between image data of the imaged surface of the substrate by the pair of upper and lower light sources. The first technical idea of the invention was focused on.

In the teaching mode, the inventor sets the angle between the substrate and the pair of upper and lower light sources and the illuminance of the upper and lower pair of light sources so that the difference between a non-defective substrate and a defective substrate is clear. In the inspection mode, by illuminating one light source with the set illuminance, irradiating the substrate and turning off the other light source, and turning on the other light source with the set illuminance, the substrate And one of the light sources is turned off, the surface of the substrate illuminated by the pair of upper and lower light sources is imaged by an imaging device, and a difference between image data of the surface of the substrate imaged by the imaging device is processed. The second technical idea of the present invention, in which the device is used to determine the quality, was focused on.

Further, as a result of further research and development, the present inventor has clarified the difference between a non-defective product and a defective product, and processes only image data in an area required for inspection.
The present invention has been achieved which achieves the object of shortening the processing time in order to take the image difference and shortening the overall inspection time.

[0008]

According to a first aspect of the present invention, there is provided an apparatus for inspecting a substrate, comprising: a pair of upper and lower light sources disposed at an interval for irradiating light to the surface of the substrate; A driving device that drives the pair of upper and lower light sources at different timings, a relative position adjusting mechanism that can adjust a relative positional relationship between the pair of upper and lower light sources, and the pair of upper and lower light sources whose relative positional relationship is adjusted And an image processing apparatus for determining whether or not the surface of the substrate is imaged by the image capturing apparatus based on a difference between image data obtained by the pair of upper and lower light sources. .

According to a second aspect of the present invention, in the substrate inspecting apparatus of the first aspect, the relative position adjusting mechanism adjusts a position of one of the upper and lower light sources. It is constituted by a position adjusting mechanism.

According to a third aspect of the present invention, in the substrate inspection apparatus according to the second aspect of the present invention, in the second aspect of the present invention, the image data of the surface of the substrate imaged by the imaging device by the pair of upper and lower light sources is obtained. An inspection frame for regulating the range of the image data from which the difference is obtained is provided.

According to a fourth aspect of the present invention, in the teaching mode, the angle between the substrate and the pair of upper and lower light sources and the illuminance of the upper and lower light sources are determined in the teaching mode. The difference between the defective product is set to be clear, and in the inspection mode, by turning on one light source with the set illuminance, the substrate is illuminated and the other light source is turned off, and the setting is performed. By illuminating the other light source with illuminance, the substrate is illuminated and the one light source is turned off, the surface of the substrate illuminated by the pair of upper and lower light sources is imaged by an imaging device, and the imaging device is imaged by the imaging device. The quality of the image data on the surface of the substrate is determined by an image processing apparatus.

According to a fifth aspect of the present invention, in the fourth aspect of the present invention, in the teaching mode, a range of image data for obtaining a difference between the image data on the surface of the substrate in the teaching mode. Is to set an inspection frame that regulates

According to a sixth aspect of the present invention, in the fifth aspect of the present invention, in the fifth aspect of the invention, in the teaching mode, the difference between the obtained image data is compared with a binary process. This is for setting a reference value for performing the operation.

[0014]

According to the first aspect of the present invention, there is provided a board inspection apparatus having the above-described configuration, wherein the driving device is different from the upper and lower light sources arranged at intervals to irradiate light to the surface of the board. Driving at the timing, the relative position adjustment mechanism adjusts the relative positional relationship between the pair of upper and lower light sources,
The imaging device captures an image of the surface of the substrate illuminated by the pair of upper and lower light sources whose relative positional relationship has been adjusted, and obtains the image based on a difference between image data of the captured surface of the substrate by the upper and lower light sources. Since the pass / fail is determined by the processing device, it is possible to clarify the difference between the non-defective product and the defective product.

According to a second aspect of the present invention, in the substrate inspection apparatus according to the first aspect, the position adjusting mechanism constituting the relative position adjusting mechanism adjusts a position of one of the upper and lower light sources. Therefore, an effect of clarifying the difference between a non-defective product and a defective product by a simple mechanism is achieved.

In the third aspect of the present invention, the board inspection apparatus according to the third aspect of the present invention is the board inspection apparatus of the second aspect, wherein the image data obtained by taking the difference between the image data of the surface of the board captured by the imaging device by the pair of upper and lower light sources. With the inspection frame that regulates the range, only the image data in the area required for inspection is processed, so the processing time for taking the image difference is shortened and the overall inspection time is shortened. To play.

According to a fourth aspect of the present invention, in the teaching mode, the angles and illuminances of the pair of upper and lower light sources are set in advance in the teaching mode so that the difference between a non-defective substrate and a defective substrate is clarified. Therefore, there is an effect that it is possible to perform an inspection based on an optimum angle and illuminance of the light source according to a substrate to be inspected.

According to the fifth aspect of the present invention, in the fourth aspect of the present invention, in the teaching mode, an inspection frame for regulating a range of image data for obtaining a difference between the image data on the surface of the substrate in the teaching mode. To set,
Since only the image data in the area required for the inspection is processed, the processing time for obtaining the difference between the images is shortened, so that the entire inspection time is shortened.

According to the sixth aspect of the present invention, in the method for inspecting a substrate according to the fifth aspect of the present invention, in the teaching mode, the difference between the obtained image data is compared by two.
Since the reference value for the value processing is set, the difference between the set reference value and the image is compared and the binarization processing is performed. This has the effect of

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention are described below.
This will be described with reference to the drawings.

(First Embodiment) A substrate inspection apparatus and an inspection method according to a first embodiment are arranged at intervals for irradiating light to the surface of a substrate 10 as shown in FIGS. And a pair of upper and lower light sources 1 and 2 and driving devices 3 and 4 for driving the upper and lower light sources 1 and 2 at different timings.
A relative position adjusting mechanism 6 capable of adjusting the relative positional relationship between the pair of upper and lower light sources; and the substrate 1 illuminated by the pair of upper and lower light sources 1 and 2 whose relative positional relationship has been adjusted.
An imaging device 8 for imaging the surface of the substrate 10; and an image processing device 5 for judging pass / fail based on a difference between image data of the upper and lower light sources 1, 2 on the surface of the substrate 10 imaged by the imaging device 8. Things.

The imaging device 8 comprises a CCD camera 81 and a lens 82 as shown in FIGS. 1 and 3, and an X-axis robot 11 and a Y-axis robot 12 in a rectangular coordinate system as shown in FIG. It is arranged on a member 13 whose position on the X axis and the Y axis is controlled.

As shown in FIGS. 1 to 3, the relative position adjusting mechanism 6 adjusts the position of the lower light source 2 of one of the pair of upper and lower light sources 1 and 2 in the Z-axis direction.
The movable member 61, the conveyor 7
It is configured so as to adjust the distance and angle between the lower light source 2 and the substrate 10 that is conveyed above and positioned and has a chip, a lead wire, and other surface mount components 9 disposed on the surface thereof.

A pair of upper and lower light sources 1 and 2 arranged at an interval are connected to a first annular ring member 14 having one end fixed to the member 13 and one end to the movable member 61 of the position adjusting mechanism 60. A plurality of light sources are arranged at regular intervals on the circumference of the lower surface of the second annular ring member 24 to which is fixed.

The CCD camera 81 and the lens 82 are arranged coaxially in the central circular openings of the first and second annular ring members 14 and 24 as shown in FIGS. The surface mounted component 9 of the substrate 10 illuminated by the pair of light sources 1 and 2 is imaged.

The driving device 3 is connected to the upper light source 1 as shown in FIG. 1, and the driving device 4 is connected to the lower light source 2 to drive the light sources 1 and 2 at an optimum illuminance. The configuration is such that when one light source is driven, the other light source is not driven.

The image processing device 5 is connected to the driving devices 3 and 4 and is constituted by a personal computer connected to the position adjusting mechanism 60. The image processing device 5 includes an angle (position) of the pair of upper and lower light sources 1 and 2, and The contents of various settings and image processing in the teaching mode for setting the illuminance and for setting the inspection frame and the reference value as the threshold value for binarization and the inspection mode for inspecting the substrate 10 according to the settings are stored in the storage device in advance. I have.

The contents of various settings and image processing in the teaching mode will be described with reference to FIG. In step 101, the substrate 10 is moved to the inspection position by the conveyor 7, and in step 102, an inspection mode is set.

In step 103, as shown in FIG. 7, an inspection frame is set so as to reduce the amount of image data and cover only a portion necessary for inspection, and an inspection frame number is set in step 104.

In step 105, the position of the lower light source 2 is adjusted by the position adjusting mechanism 60 so that the difference between a non-defective substrate and a defective substrate is clarified.
At 6, the settings are adjusted so that the upper and lower light sources 1 and 2 are driven with optimal illuminance.

In step 107, the image 1 when only the lower light source 2 is turned on is captured by the CCD camera 81, and in step 108, the image 2 when only the upper light source 1 is turned on is captured by the CCD camera 8.
Capture by 1.

In step 109, the difference between the captured image 1 and image 2 is calculated, and in step 110, a threshold value for performing binarization so that the difference between a non-defective substrate and a defective substrate is clear. Set the reference value.

In step 111, the difference between the captured image 1 and image 2 is binarized based on the set reference value, and the area is calculated and measured.
In 2, the quality of the substrate is determined based on the measured area.

If the difference between good and bad is clear and the judgment can be made well, the setting of the reference value as the threshold is completed in step 113, and the setting of the illuminance of the light sources 1 and 2 is completed in step 114. .

When all the settings are completed in step 115, the teaching is completed in step 116, and the data is saved in step 117.

The contents of the image processing in the inspection mode will be described with reference to FIG. In step 201,
The board 10 is moved to the inspection position by the conveyor 7, and in step 202, the inspection mode is read.

In step 203, the position of the lower light source 2 is adjusted by the position adjusting mechanism 60 to the position set in the teaching mode. In step 204, the upper and lower light sources 1 and 2 are set to the optimum positions. The setting is adjusted so as to be driven at an appropriate illuminance.

In step 205, only the lower light source 2 is turned on, and the image 1 is
(FIG. 7). At step 206, only the upper light source 1 is turned on, and the CCD camera 81 captures an image 2 (FIG. 8).

In step 207, the difference between the captured image 1 and image 2 (FIG. 9) is calculated, and step 208 is performed.
In step 209, the difference between the image 1 and the image 2 captured based on the set reference value is binarized (FIG. 10), and in step 209, the area (black area in FIG. Is calculated and measured, and in step 210, the quality of the substrate is determined based on the measured area.

At step 211, it is determined whether or not it is the final position. At step 212, it is determined whether or not the product is defective. If a defective product is detected, a defective number is displayed at step 213.

The board inspection apparatus and the inspection method according to the first embodiment having the above-described configuration are arranged so that, in the teaching mode, the difference between the non-defective product and the non-defective product of the substrate 10 to be inspected is clarified. The illuminance of the pair of upper and lower light sources 1 and 2, the angle (position) of the lower light source 2, an inspection frame for regulating image data to a required range, and a reference value as a threshold are set in advance for each substrate 10 to be inspected. This is a mode in which the setting is performed only once and the set data is stored in the storage device of the image processing apparatus 5.

In the inspection mode, as shown in FIG. 3, the light sources 1 and 2 are placed just above a substrate 10 to be inspected.
Then, the CCD camera 81 is moved, the lower light source 2 is turned on with the illuminance set in the teaching mode, and the angle (position) of the lower light source 2 is determined. At this time, the upper light source 1
Turns off. Thereafter, the image 1 is captured by the CCD camera 81.

Next, the upper light source 1 is turned on with the illuminance set in the teaching mode, and at this time, the lower light source 2 is turned off. Thereafter, the image 2 is captured by the CCD camera 81.

The difference between the captured image 1 and the captured image 2 is obtained only within the inspection frame set in the teaching mode,
The quality of the substrate 10 is determined by calculating the area of the binarized data (FIG. 10) of “black” or “white” which is equal to or greater than the reference value as the threshold value at which the difference is set.

That is, if the board 10 is an unsoldering defect which is a defective product to which no solder is attached, the image after the binarization processing is such that the entire inspection frame becomes "white" as shown in FIG. Is almost zero when the area of "" is obtained, and it is possible to determine a good product and a defective product based on the size of the "black" portion.

In the substrate inspection apparatus according to the first embodiment having the above-described operation, the position adjusting mechanism 60 adjusts the relative positional relationship between the pair of upper and lower light sources 1 and 2, and
Captures an image of the surface of the substrate illuminated by the pair of upper and lower light sources 1 and 2 whose relative positional relationship has been adjusted, and determines whether or not the image processing device determines pass / fail based on a difference between the captured image data of the surface of the substrate 10. Since the determination is made, the effect of clarifying the difference between the non-defective product and the defective product and ensuring the determination is achieved.

In the substrate inspection apparatus of the first embodiment, the position adjusting mechanism 60 adjusts the position of one of the upper and lower light sources 1 and 2 so that a non-defective product and a defective product can be obtained by a simple mechanism. This has the effect of clarifying the difference from the above and making sure the determination.

Further, the substrate inspection apparatus of the first embodiment
An area necessary for inspection is provided because the inspection frame is provided to regulate a range of image data on a surface of the substrate 10 imaged by the imaging device 8 by the pair of upper and lower light sources 1 and 2. Since only the image data in the image data is processed, the processing time for obtaining the difference between the images is shortened, and the effect of shortening the entire inspection time is achieved.

In the board inspection method according to the first embodiment, in the teaching mode, the angles and the illuminances of the upper and lower light sources are set in advance so that the difference between the non-defective substrate and the defective substrate 10 becomes clear. Therefore, it is possible to perform an inspection based on the angle and illuminance of the light source that is optimal for the substrate to be inspected, and it is possible to reliably determine a good product and a defective product.

Further, the board inspection method of the first embodiment is as follows.
In the teaching mode, an inspection frame is set to regulate a range of image data for obtaining a difference between the image data on the surface of the substrate 10, so that only image data in an area required for inspection is processed. This has the effect of increasing the speed, shortening the processing time, and shortening the overall inspection time.

In the method for inspecting a substrate according to the first embodiment, in the teaching mode, a reference value for binarization processing is set by comparing the obtained difference between the image data. Since the binarization process is performed by comparing the reference value with the difference between the images and the quality of the substrate is determined from the area thereof, the effect of reliably discriminating the non-defective product from the non-defective product by a simple process can be obtained. Play.

The above-described embodiments have been described by way of example only, and the present invention is not limited to these embodiments. Those skilled in the art will recognize from the claims, the detailed description of the invention, and the drawings. Modifications and additions are possible without departing from the technical idea of the present invention.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an entire board inspection apparatus according to a first embodiment of the present invention.

FIG. 2 is a perspective view illustrating a moving mechanism and an optical system of the substrate inspection apparatus according to the first embodiment.

FIG. 3 is a side view showing an optical system and a position adjusting mechanism of a lower light source in the first embodiment.

FIG. 4 is a bottom view showing the lower light source and the position adjusting mechanism in the first embodiment.

FIG. 5 is a chart showing a procedure in a teaching mode in the first embodiment.

FIG. 6 is a chart showing a procedure in an inspection mode according to the first embodiment.

FIG. 7 is an explanatory diagram illustrating an image 1 captured in the first embodiment.

FIG. 8 is an explanatory diagram illustrating an image 2 captured in the first embodiment.

FIG. 9 is an explanatory diagram illustrating an image of a difference between image 1 and image 2 in the first embodiment.

FIG. 10 is an explanatory diagram illustrating an image after a binarization process of an image of a difference between the image 1 and the image 2 in the first embodiment.

FIG. 11 is a view illustrating a case 2 of a solder failure in the first embodiment.
FIG. 4 is an explanatory diagram illustrating a value-processed image.

[Description of Signs] 1, 2 light sources 3, 4 driving device 5 image processing device 6 relative position adjusting mechanism 8 imaging device 10 substrate

Claims (6)

[Claims] A pair of upper and lower light sources disposed at intervals to irradiate light to a surface of a substrate; a driving device for driving the pair of upper and lower light sources at different timings; A relative position adjusting mechanism capable of adjusting a relative positional relationship, an image capturing apparatus that captures an image of the surface of the substrate illuminated by the pair of upper and lower light sources whose relative positional relationship has been adjusted, and an image capturing device that captures an image of the substrate captured by the image capturing apparatus. An image processing device for judging pass / fail based on a difference in image data between the pair of upper and lower light sources on the surface. 2. The substrate inspection apparatus according to claim 1, wherein the relative position adjusting mechanism is constituted by a position adjusting mechanism for adjusting a position of one of the upper and lower light sources. 3. The inspection frame according to claim 2, further comprising an inspection frame that regulates a range of image data obtained by taking a difference between image data obtained by the pair of upper and lower light sources on the surface of the substrate imaged by the imaging device. Board inspection equipment. 4. In the teaching mode, the angle between the substrate and the pair of upper and lower light sources and the illuminance of the upper and lower pair of light sources are set so that the difference between a non-defective product and a defective product of the substrate becomes clear. By illuminating one of the light sources at the set illuminance, the substrate is irradiated and the other light source is turned off, and by illuminating the other light source at the set illuminance, the substrate is irradiated. The one light source is turned off, the surface of the substrate illuminated by the pair of upper and lower light sources is imaged by an imaging device, and a difference between image data of the surface of the substrate imaged by the imaging device is determined by an image processing device. A board inspection method, characterized in that: 5. The substrate inspection method according to claim 4, wherein in the teaching mode, an inspection frame is set to regulate a range of image data for obtaining a difference between the image data on the surface of the substrate. 6. The substrate inspection method according to claim 5, wherein in the teaching mode, a reference value for performing a binarization process by comparing the obtained difference between the image data is set.