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. 08, 2005
Filed:
Mar. 18, 2004
Mikihiko Ishii, Kitaadachi-gun, JP;
Hisashi Shiozawa, Yokohama, JP;
Jun Kawakami, Mito, JP;
Yasushi Fukutomi, Sagamihara, JP;
Yutaka Ichihara, Yokohama, JP;
Mikihiko Ishii, Kitaadachi-gun, JP;
Hisashi Shiozawa, Yokohama, JP;
Jun Kawakami, Mito, JP;
Yasushi Fukutomi, Sagamihara, JP;
Yutaka Ichihara, Yokohama, JP;
Nikon Corporation, Tokyo, JP;
Abstract
A point diffraction interference measuring method comprises forming a substantially ideal spherical wave by using a point light source-generating unit, allowing a light flux composed of the spherical wave to pass through a test sample, thereafter dividing the light flux into two light fluxes by using an optical path-dividing element, allowing one light flux of the divided light fluxes to pass through a pinholeto covert the one light flux into a reference light beam which is a substantially ideal spherical wave, and detecting interference fringes generated by causing interference between the reference light beam and a measuring light beam which is the other light flux of the divided light fluxes. The wavefront aberration of the test sample can be measured by observing the interference fringes without being affected by the disturbance which would be otherwise caused by any system vibration or the like.