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.:

US 7304749 B1

PDF
Full Text
Expired
Date of Patent:
Dec. 04, 2007

Filed:

Feb. 24, 2005
Applicant:

Akinori Ohkubo, Tochigi-ken, JP;

Inventor:

Akinori Ohkubo, Tochigi-ken, JP;

Assignee:
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01B 9/02 (2006.01);
U.S. Cl.
CPC ...
Abstract

A point diffraction interferometer measures optical performance of a target optical system based on a light intensity distribution of an interference fringe through an interference between a wave front that passes the target optical system and a reference wave front generated from a pinhole, wherein the pinhole satisfies 1.05≦ellipticity≦1.16, where the ellipticity is defined as a diameter of a pinhole in a direction perpendicular to a linear polarization direction of light incident upon the pinhole, divided by a diameter of the pinhole in the linear polarization direction.


Find Patent Forward Citations

Ohkubo, Akinori. (2007). Point diffraction interferometer and exposure apparatus and method using the same (U.S. Patent No. 7304749). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/7304749

Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile

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