JPH06112700A - Inspecting apparatus for packaged board - Google Patents

Abstract

PURPOSE:To obtain an inspecting apparatus of a packaged board which can determine the quality of a packaged component correctly even when the position of the packaged board slips. CONSTITUTION:An inspecting apparatus of a packaged board which is equipped with a moving means for moving the packaged board in the direction intersecting a scanning direction perpendicularly, a laser, a laser light scanning means for making a laser light scan on the component side, a light-sensing means 8 for converting a reflected light into a prescribed electric signal, a reflecting means for leading the reflected light from the component side to the light-sensing means 8, a data computing means 11 for computing height distribution data on a packaged component on the basis of a sensed light signal, and a determining means 18 for executing determination of the quality of a packaged state by comparing the height distribution data corresponding to an inspecting area with a threshold value. Cameras 3 which pick up images of a plurality of marks provided on the component side and output image data composed of a luminance data group of each pixel, a corrective amount computing means 15 which computes a slippage in a direction theta of the packaged board from the image data containing each mark, and an inspection area correcting means 16 which corrects the position of the inspection area on the basis of a corrective amount, are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting board inspection apparatus for making a quality judgment of a component mounted on a printed circuit board by using reflected light during laser beam scanning.

[0002]

2. Description of the Related Art Conventionally, Japanese Patent Application Laid-Open No. 4-86548 has been known as a disclosure of this type of inspection apparatus.

This inspection apparatus includes a table for moving a mounting substrate in a direction orthogonal to the scanning direction, a laser, and a rotating mirror for scanning a mounting surface with laser light through a lens.
A light receiver that converts the reflected light into a predetermined electric signal, a reflection mirror that guides the reflected light from the mounting surface to the light receiver through a lens and a rotating mirror, a light receiver that converts the reflected light into a predetermined electric signal, and a light reception signal Data calculating means for calculating height distribution data of mounted parts based on the above, height distribution data memory for storing height distribution data, inspection area memory for storing position data related to inspection area, and movement of inspection area The moving range memory that stores the data related to the above and the height distribution data corresponding to the inspection area are taken out from the height distribution data memory at each moving position and cumulatively added, and the position where this value is maximum is detected and this is calculated. It comprises a judgment processing means for comparing with a threshold value.

In the above inspection apparatus, the mounting surface is scanned with a laser beam while the mounting substrate is moved, and the reflected light is converted into an electric signal by a photodetector to obtain height distribution data of the mounted component, and the height distribution data is obtained. Once stored in the distribution data memory,
While moving the inspection area, the height distribution data corresponding to the inspection area is taken out from the height distribution data memory at each moving position and cumulatively added, and the position where this value is maximum is detected and compared with the threshold value. By doing so, the quality of the mounting state is determined.

[0005]

By the way, in the above-mentioned conventional inspection apparatus, when the mounting position of the mounting board with respect to the table is deviated, the influence of the deviation appears in the inspection area and the height distribution data of the area is deviated. Occurs, and even if the component is mounted at a normal position, it is difficult to determine that the component is defective. Although it is possible to mechanically correct the substrate position in advance, it is extremely difficult to completely eliminate minute deviations.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a mounting board inspection apparatus capable of accurately determining the quality of a mounted component even when the mounting board is misaligned. is there.

[0007]

In order to achieve the above object, according to the present invention, a moving means for moving a mounting substrate in a direction orthogonal to a scanning direction, a laser, and a laser beam scanning for scanning a mounting surface with a laser beam. Means, light receiving means for converting the reflected light into a predetermined electric signal, reflecting means for guiding the reflected light from the mounting surface to the light receiving means, and data calculating means for calculating height distribution data of the mounting component based on the received light signal In the mounting board inspection device, the height distribution data corresponding to the inspection area is compared with a threshold value to determine whether the mounting state is good or bad. A camera that outputs image data composed of a luminance data group for each pixel, a correction amount calculation unit that calculates the deviation of the mounting board in the θ direction from the image data including each mark, and the position of the inspection region based on the correction amount. It is provided an inspection area correcting means positive for.

[0008]

In the mounting board inspection apparatus according to the present invention, the mark of the mounting board is imaged by the camera before the laser beam scanning, and the deviation of the mounting board in the θ direction is calculated from the image data including each mark. The mounting board after imaging is moved and the mounting surface is scanned with a laser beam, and the height distribution data of the mounted component is obtained from the reflected light. This height distribution data is extracted corresponding to the inspection area, but at this time, the inspection area is corrected by the above-mentioned deviation. The extracted height distribution data is compared with a threshold value, and the quality of the mounting state is determined by this.

[0009]

1 to 5 show an embodiment of the present invention. FIG. 1 is a schematic perspective view of a mounting board inspection apparatus, FIG. 2 is a block diagram of an electric circuit, and FIG. 3 is a flow chart of inspection control. 4, FIG. 4 is an explanatory diagram of mark imaging, and FIG. 5 is an explanatory diagram of correction amount calculation.

First, the mechanical structure of the inspection apparatus will be described with reference to FIG. In the figure, 1 is a mounting board on which electronic components are mounted, 1a is a mark provided at two corners of the mounting board 1, and 2 is a table for moving the mounting board 1 in the direction of a white arrow (X-axis direction). Is.

Reference numeral 3 is a built-in area sensor such as CCD.
One camera is arranged above the table moving surface at an interval corresponding to the mark distance. This camera 3 measures each mark 1a on the mounting board 1 with a predetermined inspection field E.
(See FIG. 4), the image is picked up, and image data including a luminance data group for each pixel is output.

Reference numeral 4 is a laser using a semiconductor such as He-Ne as a light source, 5 is a polygonal cylindrical rotating mirror, 6 is a lens, 7 is a reflecting mirror, and 8 is a light receiving device composed of a PSD (semiconductor position detecting element). . The lens 6 and the reflection mirror 7 are arranged above the table moving surface, and the laser 4 and the rotating mirror 5 are arranged.
The light receiver 8 is arranged above the lens 6. The light from the laser 4 is irradiated on the mounting surface through the lens 6 while being rotated in the Y-axis direction by the rotating mirror 5, and the reflected light from the mounting surface is guided to the light receiver 8 through the reflecting mirror 7, the lens 6 and the rotating mirror 5. Get burned. The reflected light guided to the light receiver 8 is converted into a predetermined electric signal by the light receiver 8.

Next, the electrical configuration of the inspection device will be described with reference to FIG. In the figure, 11 is a data calculation unit for calculating height distribution data of mounted components based on a light reception signal from the light receiver 8, 12 is a height distribution data memory for storing the calculated height distribution data, and 13 is It is an inspection area memory that stores position data related to the inspection area. A plurality of inspection areas are set in the inspection area memory 13 in correspondence with the component mounting positions.

Reference numeral 14 is an image data memory for storing image data from both cameras 3, reference numeral 15 is a correction amount calculation portion for calculating a deviation of the mounting substrate 1 in the θ direction from image data including each mark 1a, and reference numeral 16 is an inspection area. It is an inspection area correction unit that performs reading and corrects the position of the inspection area based on the correction amount.

Reference numeral 17 is a threshold value memory for storing a threshold value which is a reference for quality judgment, and 18 is a quality judgment of the mounting state by comparing the height distribution data corresponding to the corrected inspection area with the threshold value. Judgment means, 19 is a CR for displaying the judgment result
T.

The above data calculation unit 11 and correction amount calculation unit 1
5, the inspection area correction unit 16 and the determination unit 18 are well-known CPUs
And performs predetermined processing according to a control program described later.

The operation and processing procedure of the inspection apparatus will be described with reference to FIGS. 4 to 6.

The table 2 on which the mounting board 1 is placed is stopped at the image pickup position before the laser beam scanning as shown in FIG. The inspection field E including the mark 1a of the mounting substrate 1 in the stopped state is imaged by both cameras 3 (s1 in FIG. 3).

The image data output from both cameras 3 is temporarily stored in the image data memory 14 (s2 in FIG. 3).
The image data including the mark 1a stored in the image data memory 14 is combined on one screen as shown in FIG. 5, and the deviation of the mounting substrate 1 in the θ direction is calculated (s in FIG. 3).
3). Specifically, the straight line S connecting the marks 1a on the composite screen is obtained, and the inclination θ1 of the straight line S is calculated by a trigonometric function from the inter-mark distance on the straight line S and the X-direction deviation ΔX or the Y-direction deviation ΔY of the mark 1a. Is calculated. Further, without obtaining the straight line S, the inclination θ1 of the straight line S is calculated from the X-direction deviation ΔX and the Y-direction deviation ΔY of the mark 1a by a trigonometric function.
It is also possible to calculate The correction amount θ1 obtained here is stored in the RAM (s4 in FIG. 3).

The mounting board 1 after the image pickup is fed under the lens 6 and its mounting surface is scanned with a laser beam (s in FIG. 3).
5). Here, the laser light is rotationally irradiated in a direction (Y-axis direction) orthogonal to the moving direction (X-axis direction) of the mounting substrate 1,
As the mounting substrate 1 is fed, the entire mounting surface is scanned. The reflected light at the time of scanning is guided to the light receiver 8 through the reflection mirror 7, the lens 6, and the rotating mirror 5, and is converted into a predetermined electric signal by the light receiver 8.

The received light signal converted by the light receiver 8 is converted into height distribution data by the data calculation unit 11 by an appropriate calculation formula (s6 in FIG. 3), and is temporarily stored in the height distribution data memory 12. (S7 in FIG. 3). After the data conversion processing, the position data related to the inspection area is read from the inspection area memory 13, and at the same time, the correction amount θ1 is read and the position data, that is, the inspection area is θ of the mounting board 1.
It is corrected by the amount of deviation in the direction (s8 to s9 in FIG. 3). If the mounting board 1 is displaced as shown in FIG.
A similar inclination is given to the inspection area.

After the inspection area is corrected, the height distribution data corresponding to the corrected inspection area is read from the height distribution data memory 12, and at the same time, the threshold value corresponding to the inspection area is read from the threshold value memory 17. Then, the quality of the mounting state is determined by comparing the two (s11 to s1 in FIG. 3).
3). The determination result is sequentially displayed on the CRT 19 (14, s15 in FIG. 3).

As described above, according to the mounting board inspection apparatus described above, the deviation in the θ direction of the mounting board 1 is detected before the laser beam scanning, and the inspection area of the height distribution data is corrected by the deviation. Therefore, even if the mounting substrate 1 on the table has a positional deviation, it is possible to accurately set the inspection region again in accordance with the deviation and accurately determine the quality of the mounted component. Further, it is possible to save the trouble of correcting the substrate position in advance of the laser beam scanning, which contributes to the reduction of the inspection time, and the structure can be simplified by reducing the degree of freedom of the table accordingly.

In the above-mentioned embodiment, the two marks are picked up by the two cameras on the mounting board, but one camera can be obtained by moving and stopping the mounting board by the distance between the marks. Each mark can also be imaged with. Further, the laser beam scanning means including a laser, a rotating mirror and a lens, and the reflecting means including a reflecting mirror, a lens and a rotating mirror may be replaced by a well-known structure other than the illustrated example.

[0025]

As described above in detail, even if the mounting substrate to be inspected has a positional deviation, the inspection area can be properly set in accordance with the deviation and the quality of the mounted component can be accurately judged. In addition, it is possible to save the labor of correcting the substrate position in advance of the laser beam scanning, which contributes to the reduction of the inspection time, and the degree of freedom of the table can be reduced by that amount to simplify the structure.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of a mounting board inspection apparatus showing an embodiment of the present invention.

FIG. 2 is a block diagram of an electric circuit.

FIG. 3 is a flowchart of inspection control

FIG. 4 is an explanatory diagram of mark imaging.

FIG. 5 is an explanatory diagram of correction amount calculation.

[Explanation of symbols]

1 ... Mounting board, 1a ... Mark, 2 ... Table, 3 ... Camera, 4 ... Laser, 5 ... Rotating mirror, 6 ... Lens, 8 ... Photoreceiver, 11 ... Data operation part, 15 ... Correction amount operation part, 16
... inspection area correction unit, 18 ... determination unit.

Claims (1)

[Claims] 1. A moving means for moving a mounting substrate in a direction orthogonal to a scanning direction, a laser, a laser beam scanning means for scanning a mounting surface with a laser beam, and a light receiving means for converting reflected light into a predetermined electric signal. A reflection means for guiding the light reflected from the mounting surface to the light receiving means, a data calculation means for calculating height distribution data of the mounted parts based on the light reception signal, and a threshold value for height distribution data corresponding to the inspection area. A mounting board inspecting device comprising a judging means for judging whether the mounting state is good or bad, and a camera for picking up an image of a plurality of marks provided on the mounting surface and outputting image data consisting of a luminance data group for each pixel. A correction amount calculation means for calculating the deviation of the mounting board in the θ direction from the image data including each mark, and an inspection area correction means for correcting the position of the inspection area based on the correction amount. Mounted board inspection device.