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:
Sep. 16, 2008
Filed:
Sep. 13, 2007
Akio Atsuta, Yokosuka, JP;
Masahiko Igaki, Yokohama, JP;
Akio Atsuta, Yokosuka, JP;
Masahiko Igaki, Yokohama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
An optical encoder equipped with an origin detection apparatus has a scale provided with an optical grating, a plurality of light receiving elements that is provided in association with the pitch of the optical grating and movable relative to the scale and a light source that illuminates the light receiving elements with light through the scale. An optically discontinuous portion is provided in the optical grating of the scale, a change of a light beam that occurs over a certain length of section at the time when a light beam corresponding to the discontinuous portion is incident on the light receiving elements, a change occurring in that section is detected, calculation is performed, and an origin position is detected from the result of the calculation.