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:
Apr. 09, 2013
Filed:
Jun. 03, 2009
Hajime Nakajima, Tokyo, JP;
Takuya Noguchi, Tokyo, JP;
Takeshi Musha, Tokyo, JP;
Youichi Omura, Tokyo, JP;
Toshiro Nakashima, Tokyo, JP;
Tatsuya Nagatani, Tokyo, JP;
Takashi Iwamoto, Tokyo, JP;
Hajime Nakajima, Tokyo, JP;
Takuya Noguchi, Tokyo, JP;
Takeshi Musha, Tokyo, JP;
Youichi Omura, Tokyo, JP;
Toshiro Nakashima, Tokyo, JP;
Tatsuya Nagatani, Tokyo, JP;
Takashi Iwamoto, Tokyo, JP;
Mitsubishi Electric Corporation, Tokyo, JP;
Abstract
Present invention provides an optical encoder capable of improving the precision of an interpolation angle in a single signal track, in an encoder of sine-wave angle interpolation type. The optical encoder includes a waveform, in which a phase-modulated wave is superimposed in a predetermined period over a sine-wave of a fundamental period, as a signal track (), and an optical detector () for extracting the sine signal and the cosine signal of the phase-modulated wave. An operation unit () operates electric angles individually from the output signals of a first optical detector pair and a second optical detector pair belonging to the optical detector, and determines the sum and difference of the electric angles, thereby acquiring the electric angle and the phase-modulated wave of the fundamental period.