CONNECTION STATE DETECTION METHOD OF CIRCUIT PARTS

摘要

PURPOSE:To judge whether the connection state of packaged parts on a printed circuit board is proper or not by converting the planar distribution of shading value of inspection part of an image of the conforming printed circuit board to a data set corresponding to the conforming printed circuit board and then obtaining an average degree of conformance. CONSTITUTION:Characteristics of an image are extracted from a data set which expresses images including the image of parts 2 which are obtained by an image pick-up device 7. An average degree of conformance as an inspection standard can be obtained by applying the method to a conforming printed circuit board and the degree of conformance can be obtained by applying it to a printed circuit board 1 to be inspected. The connection state of the printed circuit board 1 is judged by comparing the degree of conformance with the average degree of conformance. Namely, the planar distribution of the shading value is converted to a vector with a specified dimension to obtain a conforming article vector for the image of the part to be inspected of the conforming printed circuit board and then a conforming article characteristic vector is obtained from the conforming article vector set. An average approximation to characteristics of the conforming article is obtained as the average degree of conformance to obtain an inspection standard. A criterion can be set properly using the average degree of conformance.