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:
Mar. 30, 2010
Filed:
Sep. 05, 2008
Yumiko Ohsaki, Utsunomiya, JP;
Seiji Takeuchi, Utsunomiya, JP;
Yumiko Ohsaki, Utsunomiya, JP;
Seiji Takeuchi, Utsunomiya, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
The present invention provides a measurement apparatus including a first polarization control unit configured to control a polarization state of light which enters an optical system to be measured to at least two different polarization states, a wavefront splitting unit which is inserted between the first polarization control unit and the optical system, a second polarization control unit which is inserted between the optical system and an image sensor, includes a phase plate, and is configured to control the polarization state of the light, and a processing unit configured to calculate the optical characteristics of the optical system, based on a plurality of interference patterns sequentially sensed by the image sensor by rotating the phase plate.