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:
Jul. 02, 2013
Filed:
Dec. 15, 2010
Hitoshi Nakamura, Kawasaki, JP;
Hitoshi Nakamura, Kawasaki, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A rotary encoder includes two first detection units disposed at positions that are symmetrical about a rotation axis, each of the first detection units outputting an incremental signal, and second detection unit that outputs an absolute signal φ. The rotary encoder includes a storage unit that stores a plurality of formulas for correcting errors of the incremental signals, the formulas being different from each other in accordance with the signal φ, and the errors being generated due to eccentricity; a calculation unit that calculates a corrected phase φby performing operation on the incremental signals by using one of the formulas corresponding to the signal φ; and a generation unit that generates a rotation angle of the scale on the basis of the phase φand the signal φ.