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. 30, 1991
Filed:
Dec. 12, 1989
Applicant:
Inventors:
Nobuhisa Nishioki, Kawasaki, JP;
Tatsuo Itabashi, Kawasaki, JP;
Assignee:
Mitutoyo Corporation, , JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01B / ;
U.S. Cl.
CPC ...
356356 ;
Abstract
A grating-interference type displacement meter apparatus is disclosed wherein a convex lens or a concave mirror is disposed such that a focal point thereof is placed on a refraction plane or a diffraction plane of a diffraction grating, or wherein zeroth-order beams transmitted through the diffraction grating are reflected back in the same direction by a rectangular prism or a triangular prism for reentrance thereof onto the diffraction grating. Hereby, a plurality of optical beams produced by the diffraction grating are directed to propagate parallely to directions of propagation thereof defined in its design.