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:
Oct. 23, 2007
Filed:
Aug. 23, 2004
Toru Oka, Tokyo, JP;
Yoichi Ohmura, Tokyo, JP;
Hajime Nakajima, Tokyo, JP;
Masahiko Sakamoto, Tokyo, JP;
Toshikazu Kitagaki, Tokyo, JP;
Toru Oka, Tokyo, JP;
Yoichi Ohmura, Tokyo, JP;
Hajime Nakajima, Tokyo, JP;
Masahiko Sakamoto, Tokyo, JP;
Toshikazu Kitagaki, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
In an optical encoder comprising an optical scale in which a light transmission portion and a light non-transparent portion are arranged and an output pattern obtained by emitting an incident light functions as an optical code, a light source portion and a light detecting portion, the light non-transparent portion is constituted of at least one pair of inclined surfaces which are opposed in such a manner as to become farther away from each other towards the side where the incident light enters and set so that an incident angle of the optical axis of the incident light from the light source should not be smaller than a critical angle of incidence, and the light non-transparent portion is constructed so that the incident light which enters one inclined surface should be totally reflected thereon to enter the other inclined surface and then at least part of the incident light should be reflected on the other inclined surface, and a reflected light which is reflected on the other inclined surface should not enter a light emitting portion of the light source and a reflecting portion around the light emitting portion.