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:
Feb. 17, 1987
Filed:
Apr. 18, 1985
Toshio Kanoh, Tokyo, JP;
Taira Kouchiwa, Kanagawa, JP;
Ricoh Company Ltd., Tokyo, JP;
Abstract
A fringe scanning shearing interferometer includes a converter lens for converting a wavefront reflected by an object under test illuminated with light into an approximately parallel wavefront, a beam splitter for dividing the approximately parallel wavefront into first and second wavefronts travelling in two directions, a pair of first and second prisms disposed respectively adjacent to the beam splitter in equally spaced relation thereto, a displacement mechanism for displacing the first prism in a direction normal to the direction in which the first wavefront falls on the first prism, a shearing device for slightly displacing the second prism in the same direction as that in which the second wavefront falls on the second prism, a photodetector, and a focusing lens for focusing the first and second wavefronts having passed respectively through the first and second prism, on the photodetector to produce interference fringes thereon.