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:
Nov. 13, 2007
Filed:
Apr. 21, 2005
Akinori Ohkubo, Tochigi-ken, JP;
Akinori Ohkubo, Tochigi-ken, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A measuring apparatus for measuring optical performance of a test optics by using light includes a first member for generating a first ideal wave front, a second member for generating a second ideal wave front and a test wave front that reflects the optical performance of the test optics, and a detector for detecting an interference fringe between the test wave front and the second ideal wave front that passes the second member, wherein the first member and/or the second member include a first membrane having a first aperture for diffracting the light, and a second membrane having a second aperture for diffracting the light that has passed the first aperture, the second membrane being spaced from the first membrane so that the first and second apertures overlap each other.