JPH05198999A - Board inspection apparatus - Google Patents

Abstract

PURPOSE:To execute a comparison processing operation and a judgment processing operation at high speed by a method wherein the height of a component mounted on a board is found by using an output signal supplied from an image sensing means, the height is compared with a predetermined reference height and it is judged whether the board on which the component has been mounted is good or not. CONSTITUTION:The image of a board 1 on which components 6 have been mounted is picked up by using one pair of image sensing means 8, 18; a so-called binocular image sensing operation is performed. Consequently, a piece of height information can be obtained from the dislocation amount of images of the same components 6 in output signals can be obtained from the pair of image sensing means 8, 18 by using a signal processing means 15. The piece of height information on the components is compared with a piece of reference height information on the components decided in advance so as to correspond to a piece of two-dimensional information on the board 1; it can be judged whether the board 1 on which the components 6 have been mounted is good or not. Thereby, the formation processing operation, the comparison processing operation and the judgment processing operation of the piece of height information by means of the signal processing means 15 can be performed at extremely high speed, and whether a component-mounted board 7 is good or not can be judged in a short time.

Description

Detailed Description of the Invention

[0001]

The present invention relates to, for example, an IC chip,
The present invention relates to a board inspection device that determines the quality of a board on which a resistance chip, an electrolytic capacitor chip, or the like is mounted in a non-energized state.

[0002]

2. Description of the Related Art FIG. 2 shows the structure of a substrate inspection apparatus according to the first conventional technique. In FIG. 2, parts 6 such as a resistor chip 2, an IC chip 3, a porcelain capacitor chip 4 and an electrolytic capacitor chip 5 are mounted on a substrate 1 by soldering. In this way, parts such as chip parts 6
The board mounted by soldering is hereinafter referred to as a component mounting board 7 as necessary.

A CCD camera 8 is arranged above the component mounting board 7. The CCD camera 8 stores a CCD image pickup device which is an area sensor (not shown).

In the board inspecting apparatus configured as shown in FIG. 2, the CCD camera 8 photographs the entire surface of the component mounting board 6 to determine the presence or absence of the component 6 mounted on the board 1 to mount the component. The quality of the substrate 6 can be determined.

However, since the board inspection apparatus according to the first technique is a so-called monocular system, it can obtain only two-dimensional information about the component 6 mounted on the board 1. For this reason, for example, when the component 6 is lifted up, or when the components 6 having the same shape in plan view and different heights are erroneously mounted (erroneously mounted), it cannot be recognized as a “defective”. There was a problem.

Although there are some parts 6 having symbols such as characters printed on the upper surface thereof, in general, the symbols such as characters are considerably small, and the symbols are recognized by the CCD camera 8. It is extremely difficult to recognize, and if the part 6 is not printed with a symbol such as a character, it cannot be recognized.

FIG. 3 shows a configuration of a substrate inspection apparatus according to a second conventional technique for solving the problems in the substrate inspection apparatus according to the first technique described above. In addition, in FIG.
Since the component mounting board 7 is the same as that shown in FIG. 2, its description is omitted.

In the board inspecting apparatus shown in FIG. 3, a laser height measuring machine 9 is arranged at a predetermined height H above the component mounting board 7. When the substrate inspection apparatus of the example of FIG. 3 is used, the laser height measuring machine 9 is placed on the plane of the height H.
The three-dimensional information of the component 6 mounted on the substrate 1 is obtained by scanning in the XY two-dimensional direction with.

Based on the thus obtained three-dimensional information, it is possible to judge whether or not the correct component 6 is correctly mounted on the board 1.

[0010]

However, the substrate inspection apparatus using the laser height measuring machine 9 requires a considerable time for the above-mentioned XY two-dimensional scanning, and as a result,
There is a problem that it takes a considerable amount of time to judge the quality of component mounting. Further, there is a problem that the board inspection device using the laser measuring machine 9 cannot recognize the symbols such as characters printed on the component 6 at all.

The present invention has been made in view of the above problems, and provides a board inspection apparatus capable of obtaining three-dimensional information in a short time and determining whether a component mounting board is good or bad in a short time. The purpose is to

[0012]

The board inspection apparatus of the present invention comprises:
For example, as shown in FIG. 1, a board 1 on which a component 6 is mounted
In the board inspection device for determining the quality of the pair of image pickup means 8 and 18 arranged parallel to the mounting surface of the board 1.
And a signal processing unit 15 to which the output signals of the image pickup units 8 and 18 are supplied, and the signal processing unit 15 detects the output signals from the image pickup units 8 and 18 of the component 6 mounted on the substrate 1. The height is obtained, and the obtained height is compared with a predetermined reference height to determine the quality of the board 1 on which the component 6 is mounted.

[0013]

According to the board inspection apparatus of the present invention, the board 1 on which the component 6 is mounted is picked up by the pair of image pickup means 8 and 18, so that so-called twin-lens image pickup is performed. Therefore, the signal processing means 15 causes the pair of imaging means 8, 18
Height information can be obtained from the amount of positional deviation of the image of the same component 6 in the output signal of. Then, the signal processing means 15 compares the height information of this component with the reference height information of the component which is determined in advance corresponding to the two-dimensional information on the substrate 1 and mounts the component 6. The quality of the substrate 1 can be determined.

The height information creation / comparison / determination processing by the signal processing means 15 can be performed at extremely high speed, and as a result, the quality of the component mounting board 7 can be determined in a short time.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the substrate inspection apparatus of the present invention will be described below with reference to the drawings. In the drawings referred to below, the same components as those shown in FIGS. 2 and 3 described above are designated by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 1, parts 6 such as a resistor chip 2, an IC chip 3, a magnetic capacitor chip 4 and an electrolytic capacitor chip 5 are mounted on a substrate 1 by soldering. The board on which the component 6 such as the chip component is mounted by soldering is hereinafter referred to as a component mounting board 7 as necessary. Note that the present invention can be applied to a state in which the component 6 is attached to the substrate 1 with an adhesive before being soldered to the substrate 1. It also includes a substrate in a state where the component 6 is attached to the substrate 1 with an adhesive material.

Above the component mounting board 7, there are two of the same construction.
The CCD cameras 8 and 18 (a pair of image pickup means) are provided on the substrate 1.
It is placed parallel to the mounting surface of. Each CCD camera 8 and 18 has a CC which is an area sensor (not shown).
The D image sensor is stored. The optical axes 11 and 12 of the CCD cameras 8 and 18 are adjusted so as to intersect at one point on the substrate 1.

The respective video signals output from the CCD cameras 8 and 18 are supplied to the signal processing device 15 (signal processing means). The video signal supplied to the signal processing device 15 is converted into video data through an A / D converter (not shown), and the data for one screen is stored in the memories 16 and 17, respectively. In the height data generator 19 based on the video data stored in the memories 16 and 17, Z-axis data indicating unevenness at each XY coordinate point on the component mounting board 7, that is, height data (hereinafter, measured height). Hm (referred to as data) is created.

The measured height data Hm is the same component generated due to the difference in height of the individual components 6 in each image formed on each area sensor (not shown) of the CCD cameras 8 and 18. 6 can be created based on the amount of positional deviation between the two images. Therefore, the measurement height data Hm can be created from the video data recorded in the memory 16 and the memory 17. Such a method of creating the measured height data Hm is an application of a well-known stereo photography method of creating a topographic map using an aerial photograph.

On the other hand, in advance, Z-axis data at each XY coordinate point on the component mounting board which is a reference without misplacement of the component 6, that is, height data (hereinafter referred to as reference height data) Hr is memorized. It is stored in 21.

Therefore, in the comparator 22, the measured height data Hm created by the height data creator 19 and the memory 2 are stored.
The reference height data Hr at the same point on the X-Y coordinates stored in 1 are compared.

The comparison result of the comparator 22 is the judgment device 23.
Is determined by. The determiner 23 determines that the component mounting board 7 is a good product when the comparison result is within a preset positional deviation allowable value, and determines a defective product otherwise. For example, when the component 6 is lifted up or when components having the same shape in plan view but different heights are erroneously mounted (erroneously mounted), they are determined to be “defective”.

Output determination data indicating whether the product is a non-defective product or a defective product is output from the determiner 23, printed out through the printer 24, and visualized as a hard copy 25. In addition to simply printing out the quality judgment, it is also possible to print out the measured height data Hm and the reference height data Hr at each XY coordinate point on the substrate 1. Further, the output data of the signal processing device 15 may be displayed on a monitor as an image.

Each component in the signal processing device 15
The operations of the CCD cameras 8 and 18 and the printer 24 are controlled by a controller (not shown).

As described above, according to the above-described embodiment, since the component mounting board 7 is imaged by the pair of CCD cameras 8 and 18, so-called twin-lens photography is performed. Therefore, the height data generator 19 constituting the signal processing device 15 can generate the measured height data Hm from the positional deviation amount of the images of the same component 6 in the output signals of the pair of CCD cameras 8 and 18. Then, by the comparator 22 configuring the signal processing device 15, the component 6
Of the measured height data Hm and the reference height data H of the corresponding component 6 which is determined in advance corresponding to the two-dimensional information on the board.
The quality of the component mounting board 7 can be judged by the judging device 23 by comparing r with r.

In this case, according to the above-described embodiment, there is no need to perform physical XY two-dimensional scanning as in the laser height measuring machine 9 described in the section of the prior art. Compared with the board inspection device using the measuring machine 9, C
The height data can be created, compared, and determined by the CD cameras 8 and 18 and the signal processing device 15 in a very short time. Therefore, as a result, the quality of the component mounting board 7 can be inspected accurately in a short time, in other words, at high speed and with high accuracy. Moreover, this so-called 2
The board inspection device using eye-based imaging (two-eye object recognition method)
Since the so-called monocular substrate inspection apparatus of FIG. 2 described in the section of the related art can also be modified and manufactured, it is possible to suppress an increase in cost to a low level, and to compare with the laser height measuring machine 9. It can be manufactured at low cost.

The present invention is not limited to the above-mentioned embodiments, and it goes without saying that various configurations can be adopted without departing from the gist of the present invention.

[0028]

As described above, according to the board inspection apparatus of the present invention, the board on which the components are mounted is picked up by the pair of image pickup means. Therefore, the signal processing means can obtain the height information from the positional deviation amount of the images of the same component in the output signals of the pair of imaging means. Then, the signal processing means compares the obtained height information of the component with the reference height information of the component which is determined in advance corresponding to the two-dimensional information on the board, and mounts the component. The quality of the substrate can be determined.

Creation of the height information by the signal processing means
Since the comparison / judgment processing can be performed at an extremely high speed, the result is that the quality of the component mounting board can be judged in a short time.

[Brief description of drawings]

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

FIG. 2 is a diagram showing a configuration of a board inspection apparatus according to a conventional technique.

FIG. 3 is a diagram showing another configuration of a conventional board inspection device.

[Explanation of symbols]

 1 board 6 parts 7 parts mounting board 8, 18 CCD camera 15 signal processor 19 height data generator 22 comparator 23 judgment device Hm measured height data Hr reference height data

Claims (1)

[Claims] 1. A board inspection apparatus for determining the quality of a board on which a component is mounted, wherein a pair of image pickup means arranged parallel to a mounting surface of the board and output signals of these image pickup means are supplied. Signal processing means, wherein the signal processing means obtains the height of the component mounted on the board from the output signal supplied from the image pickup means, and obtains the obtained height and a predetermined reference height. The board inspection device is characterized in that the quality of the board on which the above component is mounted is determined by comparing the above.