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:
Jan. 11, 2022
Filed:
Jul. 02, 2020
Canon Kabushiki Kaisha, Tokyo, JP;
Chihiro Nagura, Yokohama, JP;
CANON KABUSHIKI KAISHA, Tokyo, JP;
Abstract
In order to provide an optical encoder with high resolution, the optical encoder includes: a rotary scale provided with a grating pattern having a first radial pattern and a plurality of concentric circular patterns disposed at predetermined intervals; and a light receiving element which detects a first interference fringe formed by the first pattern having a first period in the circumferential direction, a second interference fringe which is diffracted in a direction of the first interference fringe by a grating pattern having a second period in the circumferential direction disposed at a different radial position so that the second interference fringe has a period closer to the first period than the second period.