The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 18, 1995
Filed:
Aug. 01, 1994
Ryuji Kitakado, Kyoto, JP;
Hisayuki Tsujinaka, Kyoto, JP;
Tetsuo Hoki, Kyoto, JP;
Takao Omae, Kyoto, JP;
Dainippon Screen Mfg. Co., Ltd., Kyoto, JP;
Abstract
A printed pattern is provided with a wiring pattern having a land and a through hole surrounded by the land. The wiring pattern and the through hole are read by a photoelectric image sensor to obtain a pattern image and a hole image, respectively. A pattern gauge image is defined by the pattern image, and a hole gauge image having a ring-like shape is obtained from the hole image. A logical product between the inversion image of the pattern gauge image and the hole gauge signal provides a protrusion region image. Since the hole gauge image has an isotropic contour, the minimum annular width of the land is detected, independent of the direction in which the through hole is deviated from the land.