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:
Jul. 23, 1991
Filed:
Sep. 27, 1990
Applicant:
Inventor:
Yoshiya Matsui, Yokohama, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01B / ;
U.S. Cl.
CPC ...
356359 ; 356360 ;
Abstract
A measuring method and apparatus for measuring the shape of an optical surface using Fizeau interference is disclosed. The states of three surfaces are determined by measuring Fizeau fringes between all possible pairs of said surfaces. In at least one of these measurements means for reversing the coordinate axis in the beam is provided.