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:
Jul. 20, 2004
Filed:
Mar. 27, 2002
Satoshi Imaizumi, Anjo, JP;
Nidek Co., Ltd, Gamagori, JP;
Abstract
A surface shape measurement apparatus for measuring a shape of an object to be examined by a simple mechanism for rotating a reference grid. The apparatus comprises a stage on which the object is rested, a reference grid disposed in parallel to the stage, illumination means for illuminating the reference grid and projecting an grid pattern onto the object surface, photographing means for photographing the grid pattern projected onto the object surface through the reference grid and obtaining an image of moiré fringes, rotation means for rotating the reference grid about an axis normal to a grid surface of the grid plate, and analysis means for analyzing the shape of the object surface based on information about a rotation angle of the reference grid and intensity of the moiré fringes.