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:
May. 09, 1989
Filed:
Nov. 12, 1987
Kanzaki Paper Manufacturing Co., Ltd., Tokyo, JP;
Abstract
A surface inspection apparatus having a microscope and a television camera is disclosed. The inspection apparatus samples a signal portion from a horizontal scanning portions of the video signal produced by the television camera, compares the instantaneous voltages of a filtered signal of said sampled portion removing low-frequency components with a reference voltage, counts the number of pulses constituted from the high level portions of said filtered signal higher than said reference voltage sequentially moves the focal point of the microscope step by step relative to the object surface, compares the present pulse count with the previous pulse count thereof at just prior step of the moving of the focal point, and decides the focal point in the position corresponding to the maximum number of pulses to control the moving of the focal point for correctly setting the focal point in said corresponding position.