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:
Mar. 31, 2015
Filed:
Feb. 10, 2012
Haruhiko Horiguchi, Tokyo, JP;
Chihiro Nagura, Yokohama, JP;
Haruhiko Horiguchi, Tokyo, JP;
Chihiro Nagura, Yokohama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
An optical encoder includes a light source, a scale which is irradiated by the light source and has a fine pitch pattern and a coarse pitch pattern in one track, a photo detector array which detects transmitting light or reflected light from the scale which are emitted from the light source, a signal processing unit including a first initial-stage amplifier unit that generates a position detection signal from the photo detector array, and a control unit that uses an output signal from the first initial-stage amplifier unit to control a light amount variation of the light source. The optical encoder can operate in a high resolution detection mode that forms the photo detector array at a first pitch to detect the fine pitch pattern and a low resolution detection mode that forms the photo detector array at a second pitch to detect the coarse pitch pattern.