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:
Jun. 10, 2008
Filed:
Aug. 28, 2006
Applicants:
Masahiko Igaki, Yokohama, JP;
Akio Atsuta, Yokosuka, JP;
Inventors:
Masahiko Igaki, Yokohama, JP;
Akio Atsuta, Yokosuka, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01D 5/34 (2006.01);
U.S. Cl.
CPC ...
Abstract
At least one exemplary embodiment is directed to an optical encoder which includes a first diffraction grating having a desired optical effective aperture ratio at an appropriate gap position so as to eliminate and/or reduce high-harmonic components from the light intensity distribution of interference fringes and reduce high-order spatial frequency components overlapped on a displacement signal of the interference fringes formed by the first diffraction grating.