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:
Aug. 13, 1991
Filed:
Jun. 22, 1989
Applicant:
Inventors:
Masaaki Tsukiji, Tokyo, JP;
Tetsuharu Nishimura, Kawasaki, JP;
Satoshi Ishii, Tokyo, JP;
Koh Ishizuka, Urawa, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01B / ;
U.S. Cl.
CPC ...
33702 ; 33707 ;
Abstract
A scale, for measuring the displacement of an object to be examined, has a division and a mark for alignment of the division, and a displacement measuring apparatus, for measuring the displacement of a scale, has a device for reading the division of the scale and a detector for detecting the positional error of the division relative to the direction of the displacement.