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:
May. 03, 2016
Filed:
Feb. 14, 2013
Mitutoyo Corporation, Kawasaki-shi, Kanagawa, JP;
Kenichi Hayashi, Kawasaki, JP;
Hiroaki Kawada, Kawasaki, JP;
MITUTOYO CORPORATION, Kawasaki-Shi, JP;
Abstract
A photoelectric encoder includes an irradiation unit configured to apply first and second irradiation light beams having a first linear polarization direction, a scale configured to produce first and second diffraction light beams having the first linear polarization direction by diffracting the first and second irradiation light beams, respectively, the scale having a glass plate whose front surface has a grating shape, a polarizing unit configured to convert the first diffraction light beam into a third diffraction light beam having a second linear polarization direction which is perpendicular to the first linear polarization direction, to produce first and second composite light beams by combining the second diffraction light beam and the third diffraction light beam, and to convert the first composite light beam into a circularly polarized third composite light beam, and a light receiver configured to receive the second composite light beam and the third composite light beam.