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:
May. 25, 1976
Filed:
Apr. 16, 1975
Applicant:
Inventor:
Francis Hughes Smith, York, EN;
Assignee:
Vickers Limited, London, EN;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01B / ; G02B / ;
U.S. Cl.
CPC ...
3561 / ; 356109 ; 350 12 ;
Abstract
An interferometric apparatus comprises an optical assembly which simultaneously directs two mutually coherent light pencils at different respective angles of incidence towards a point on a surface and receives the reflected light pencils therefrom. The assembly includes optical means bringing the reflected pencils at least partially into coincidence so that they can interfere optically in a manner varying with variation in the distance of points on the surface from a reference plane. The assembly may be combined with a microscope to form a 'pupil-shearing micro-interferometer' for investigating surface topography.