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. 05, 2005
Filed:
Oct. 23, 2002
Shigeki Kato, Tochigi, JP;
Shigeki Kato, Tochigi, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
An interferometer or an interference position measuring device is constituted so that a low coherency light source (multi-mode semiconductor layer) or a plurality of light sources with different wavelengths are used as a light source, a light flux is split into two light fluxes in a light transmitting member, one light flux (reference light flux) is emitted to a reference mirror fixed to an optical head, and the other light flux is emitted to an object to be measured which moves or displaces, the respective reflected light fluxes are multiplexed in the transmitting member so that an interference light flux is obtained, a specified wavelength light is extracted by a wavelength selecting filter through which only a specified wavelength light transmits so as to be detected by a light receiving element.