JPH03220406A - Inspection device of bend of fic lead - Google Patents

Abstract

PURPOSE:To enable precise detection of the bend of a lead by providing an illuminator, a camera for taking in an image of a component to be inspected, a binary-coding circuit, an inspection area storage circuit, an inspection area generating circuit and a determination circuit. CONSTITUTION:An illuminator 1 applies a light to a component to be inspected and a camera 2 takes in an image thereof and outputs a gradation-density image signal (a). A binary-coding circuit 3 receives the signal (a) as an input, converts it into '1' corresponding to a bright part and '0' corresponding to a dark part on the basis of a set level and outputs a binary-coded image signal (b). An inspection area generating circuit 4 receives the signal (b) as an input, generates an inspection area which contains a lead of the component set by an inspection area signal (c) stored in an inspection area storage circuit 5 and of which the ends in the direction (direction X) perpendicular to the lead do not touch adjacent leads on the right and the left, and outputs a binary-coded image signal (d) inside the inspection area. A determination circuit 6 receives the signal (d) as an input, detects the area of the part of the lead inside the inspection area and determines the length in the direction X. When this measured length is larger than a determination value set beforehand, it is determined that a solder ball exists.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an FIC lead bending inspection device, and more particularly to an FIC lead bending inspection device for inspecting the bending of a lead of a surface real device C soldered to a printed circuit board.

[Conventional technology]

A conventional lead bending inspection device includes a lighting device 21 that irradiates light diagonally from above between adjacent leads of a component to be inspected, a camera 22 installed above that captures an image of the component to be inspected, and a gray scale image captured by the camera. A binarization circuit 23 converts a bright part of the image signal e into a binary image signal f of "1" and a dark part of "0", and a lead bend tolerance on both sides of one lead of the component to be inspected. An inspection area storage circuit 25 stores two inspection areas to be generated at the coordinates of the limit that can be generated, and an inspection area signal g stored in the inspection area storage circuit is added to the binarized image output from the binarization circuit. It includes an inspection area generation circuit 24 that generates an inspection area, and a determination circuit 26 that determines whether there is an area of 1°' within the inspection area based on the inspection area binary image signal output from the inspection area generation circuit. configured.

Next, a conventional lead bending inspection device will be described in detail with reference to the drawings. The illumination 21 in FIG. 3 irradiates the component to be inspected with light from diagonally above. The camera 22 is attached above the part to be inspected, takes in an image of the part to be inspected, and outputs a grayscale image signal e. The binarization circuit 23 inputs the grayscale image signal e and converts it into "1°" corresponding to a bright part and °0' corresponding to a dark part according to a preset binarization level, and converts it into a binarized image signal. The inspection area generation circuit 24 inputs the binary image signal f and generates a signal on both sides of one lead of the part to be inspected, which is set by the inspection area signal g stored in the inspection area storage circuit 25. An inspection area is generated at the coordinates of the allowable limit of lead bending, and a binary image signal within the inspection area is output by extracting only the binary image within the inspection area.Determination circuit 26
Now, input the binarized image signal in the inspection area and select "1".
If there is an area of °°, it is determined that there is a solder ball.

[Problem to be solved by the invention]

The conventional soldering inspection equipment described above generates the inspection area at the coordinates of the limit where lead bending is calculated, and if there is reflected light from the lead within the inspection area, it is determined that the lead is bent. This method has a disadvantage in that it is not possible to accurately detect lead bends due to the influence of the coordinate generation accuracy of the inspection area and the processing accuracy of the pad on which the lead is placed.

[Means to solve the problem]

The lead bending inspection device of the present invention includes an illumination device that irradiates light onto the component to be inspected from diagonally above, a camera mounted above that captures an image of the component to be inspected, and a bright portion of the grayscale image captured by the camera. The dark areas in the binarized image of °1" are the binarization circuit that converts them into the binarized image of "O", and the end perpendicular to the lead includes one lead of the part to be inspected. an inspection area storage circuit that stores an inspection area that does not overlap the left and right adjacent leads; and an inspection area generation circuit that generates an inspection area stored in the inspection area storage circuit in a binary image output from the binarization circuit. The circuit detects an area of 1 part due to the reflected light from the leads in the inspection area from the inspection area binary image signal outputted from the inspection area generation circuit, and calculates the length of the area in the direction perpendicular to the leads. A determination circuit that determines that the lead is bent if the lead length is longer than a predetermined determination value.

〔Example〕

Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of the present invention. The illumination 1 shown in FIG. 1 irradiates a component to be inspected with light from diagonally above. The camera 2 is attached above the part to be inspected, takes in an image of the part to be inspected, and outputs a grayscale image signal a. The binarization circuit 3 inputs the grayscale image signal a and converts it to "1" corresponding to the bright part according to the preset binarization level.
'' and 0'' corresponding to dark areas, and outputs a binary image signal. The inspection area generation circuit 4 inputs the binary image signal C, and includes the lead of the part to be inspected set by the inspection area signal C stored in the inspection area storage circuit 5, and in the direction perpendicular to the lead ( (hereinafter referred to as the X direction)
An inspection area whose ends do not overlap the adjacent leads on the left and right is generated, and an intra-inspection-area binarized image signal d, in which only the binarized image within the inspection area is extracted, is output. In the determination circuit 6,
The binarized image signal d in the inspection area is input, the area 11 of the lead part in the inspection area is detected, and the X of the area is
The length in the X direction is determined from the difference between the maximum and minimum coordinates in the direction. If the measured length in the X direction is longer than a preset determination value, it is determined that there is a solder ball.

Next, the principle of detecting lead bending will be explained using FIG.

FIG. 2 is a pattern diagram of a binary image signal.

The dotted line area is an inspection area including the lead 8 on the pad 7 and whose ends in the direction perpendicular to the leads do not overlap the adjacent left and right leads. The illumination 1 is installed at an angle where the reflected light from the pad 7 and lead 8 enters the camera 2, and since the reflected light from the pad 7 and lead 8, which have high reflectance, is strong, the "1" of the binary image signal is The shaded area indicating the area `` is area 10 of the pad and lead portion.

The determination circuit 6 first detects the area 10 of the pad and lead portion by the reflected light from the pad and lead. Normally, the area ``1'' in the inspection area 9 is only the area 10 of the pad and lead part, but if there are solder balls, etc., the area ``1'' is the area 10 where the reflected light from the solder balls etc. Therefore, it becomes plural. As a method for detecting the areas of pads and lead parts, for example, since the inspection area 9 is generated equally from the pad 7 on the left and right sides in the X direction, the central coordinates in the X direction of the multiple pad 1'' areas are The area of "1" closest to the center coordinate in the X direction can be detected as the area 10 of the pad and lead part.Next, the length of the detected area 10 of the pad and lead part in the X direction is It is determined from the difference between the maximum coordinate XMAX and the minimum coordinate XMIN in the direction, and is compared with a preset determination value, and if it is larger than the determination value, it is determined that the lead is bent.

If the lead is not bent, the length in the X direction of the area 10 of the pad and lead portion is the pad width, but if the lead is bent and the lead protrudes from the pad, the length in the X direction of the area 10 of the pad and lead portion is the pad width. The length in this direction is the sum of the pad width and the length of the bent lead protruding from the pad. Therefore, by setting the determination value to a value that is the sum of the pad width and the allowable length of the lead that protrudes from the pad, it is possible to detect a lead that protrudes from the pad beyond the allowable amount as lead bending.

〔Effect of the invention〕

The lead bending inspection device of the present invention generates the inspection area on both sides of the lead of the component to be inspected at the coordinates of the allowable limit of lead bending, and if the reflected light from the lead enters the inspection area, it is determined to be a defect. First, create an inspection area that includes one lead so that it does not cover the adjacent left and right leads, and calculate the width of the reflected light from the pad and lead in the direction perpendicular to the lead, and calculate the length of the lead protruding from the pad. Since the determination is made based on the above, lead bending can be detected with high accuracy without being affected by the coordinate generation accuracy of the inspection area, the processing accuracy of the pad on which the lead is placed, etc.

Judgment circuit, 7...pad, 8...lead, 9...
Inspection area, 10... area of pad and lead part,
a... Grayscale image signal, b... Binarized image signal, C...
... Inspection area signal, d... Binarized image signal within the inspection area.

Claims (1)

[Claims] There is a light that shines light onto the part to be inspected from diagonally above, a camera mounted above that captures images of the part to be inspected, and bright areas of the grayscale image captured by the camera.
The dark parts of the 1" binary image are converted into 0 binary images by the binarization circuit, which contains one lead of the part to be inspected, and the ends perpendicular to the lead are left and right. an inspection area storage circuit that stores an inspection area that does not span adjacent leads; and an inspection area generation circuit that generates an inspection area stored in the inspection area storage circuit in a binary image output from the binarization circuit. Then, from the binary image signal within the inspection area output from the inspection area generation circuit, an area of "1" due to the reflected light from the lead within the inspection area is detected, and the length of the area in the direction perpendicular to the lead is determined. An FIC lead bending inspection device comprising: a determination circuit that determines that the lead is bent if it is longer than a preset determination value.