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. 18, 2017
Filed:
Jul. 10, 2014
Canon Kabushiki Kaisha, Tokyo, JP;
CANON KABUSHIKI KAISHA, Tokyo, JP;
Abstract
An interferometer includes: an optical system configured to generate interfering light by dividing light from a light source, and combining reference light and measurement light; a detector configured to detect the interfering light generated by the optical system; and an optical member configured to give spatial coherence to the light from the light source before the detector detects the light from the light source. The optical member gives higher spatial coherence in a second direction serving as a direction of a line of intersection of a cross section of a beam of the light incident on the optical member, and a plane including optical paths of the light from the light source before being divided by the optical system, the reference light, the measurement light, and the interfering light, than in a first direction perpendicular to the plane.