JP2601232B2 - IC lead displacement inspection equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an IC lead deviation inspection apparatus, and more particularly, to an IC lead deviation inspection apparatus for detecting a defect in a leading end position due to bending of an IC lead such as a QFP.

[0002]

2. Description of the Related Art An IC lead is bent at the time of transportation or the like, and the leading end of the lead is easily displaced. Therefore, it is necessary to inspect such displacement of the IC lead.

[0003] A conventional IC lead displacement inspection apparatus is based on, for example, a method for inspecting lead of a surface mounted component disclosed in Japanese Patent Application Laid-Open No. 63-161635.

FIG. 3 is a view showing a picked-up image of an IC lead for explaining an image processing step of a conventional IC lead displacement inspection apparatus. Illuminate an IC with leads on four sides,
The reflected light is incident on an imaging camera, and a signal from the imaging camera is binarized, so that optical images B1 to Bn of the lead can be obtained as shown in FIG. In this captured image, axis centers L1 to Ln are obtained within the area width of the optical images B1 to Bn for each column in the XY directions. Next, each axis center L1-L
While sequentially obtaining pitch intervals P1 to Pn for each n,
An average value of these pitch intervals P1 to Pn is calculated. By comparing the average value with each of the pitch intervals P1 to Pn, it is determined whether each of the lead pins has a bend.

[0005]

In this conventional IC lead deviation inspection apparatus, when detecting the interval between leads of an image of an IC to be inspected, the arrangement of optical images in the X and Y directions is detected, and the continuity thereof is determined. And measurement of the interval, if the image to be inspected is tilted, an error will occur in the measured value, making it impossible to perform an accurate inspection, and another means must be provided for correction. There was a point.

[0006]

SUMMARY OF THE INVENTION An IC lead displacement inspection apparatus according to the present invention includes a test image input circuit for picking up an IC lead, and a test binary image obtained by binarizing an image picked up by the test image input circuit. A binarization circuit to be created; a thinning circuit to thin the inspection binary image to create a line image using the image of the lead as a line image; an endpoint detection circuit to detect an endpoint of the line image; A circular mask generation circuit for generating a mask of a circular area of a set size centered on a circle, and a circular mask overlap detection circuit for detecting the overlap between the masks.

[0007]

Next, the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of an IC lead deviation inspection apparatus according to one embodiment of the present invention.

An inspection image input circuit 1 outputs an inspection image a obtained by imaging an inspection target IC having leads. The inspection image a is binarized by the binarization circuit 2 to create a binary image b. Next, the binary image is thinned by the thinning circuit 3 so that the image of the lead portion has a width of one pixel, and a line image c is created. The end point detection circuit 4 obtains a point at the tip of the line image c, and outputs the obtained position of each end point as an end point position d.
The circular point mask generation circuit 5 generates a circular area e having a size corresponding to the allowable value of the lead interval with each detected end point position d as the center. When the overlapping of the respective circular areas e occurs, the circular mask overlapping detecting circuit 6 outputs it as a defect 7.

Next, the processing steps of this embodiment will be described with reference to FIG.

FIG. 2 shows a binary image b obtained by binarizing the image to be inspected d, reference numeral 10 denotes an image of the IC body, and reference numeral 11 denotes a lead image. By thinning the binary image b, the portion of the lead 11 becomes a line image 12. This line drawing 1
Each of the two end points 13 is detected by using a mask process or the like which is usually performed, and a circular mask 14 having a size defined by the designed lead interval is generated around each of the end points 13. When the leads of the IC are normal, the circular masks 14 do not overlap with each other. However, when the leads are bent, the overlapping 15 of the circular masks 14 is generated. Can be determined. In addition, by changing the size of the circular mask, it is possible to define an allowable value of a turn of a lead for detecting a defect.

[0012]

As described above, the IC lead inspection apparatus of the present invention detects the leading end of an IC and generates a circular mask having a size corresponding to the lead interval with each point as the center. Since the defect of the approach of the lead caused by the bending of the lead due to the overlap of the circular mask is detected,
Even if the direction of the lead C is inclined, the defect can be detected directly without using any means such as inclination correction. Further, there is no need to input lead position information.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of an IC lead deviation inspection apparatus according to the present invention.

FIG. 2 is a diagram showing an example of a binary image b in FIG.

FIG. 3 is a diagram illustrating an inspection method in a conventional IC lead deviation search device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Inspection image input circuit 2 Binarization circuit 3 Thinning circuit 4 Endpoint detection circuit 5 Circular mask generation circuit 6 Circular mask overlap detection circuit 7 Defect 10 IC 11 Lead 12 Line drawing 13 Endpoint 14 Circle mask 15 Defect a Image to be inspected b 2 Value image c-line image d Endpoint position e circular area

Claims (1)

(57) [Claims] 1. An inspection image input circuit for imaging an IC lead, a binarization circuit for generating an inspection binary image obtained by binarizing an image captured by the inspection image input circuit, A thinning circuit that performs thinning processing to create a line image using the image of the lead as a line image, an end point detection circuit that detects an end point of the line drawing, and a mask of a circular area having a set size centered on the end point. A circular mask generating circuit for generating,
An IC lead misalignment inspection apparatus, comprising: a circle mask overlap detection circuit for detecting the overlap between the masks.