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:
Jan. 04, 1977
Filed:
Sep. 15, 1969
Applicant:
Inventor:
Laurence S Watkins, Hopewell, NJ (US);
Assignee:
Western Electric Company, Inc., New York, NY (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01B / ; G02B / ;
U.S. Cl.
CPC ...
356165 ; 3501 / ; 356 71 ;
Abstract
An intensity-type optical spatial filtering system is arranged to form a composite visual image of all nonperiodic errors in a photomask or other two-dimensional pattern which contains an array of regularly spaced, normally identical elements. A coherent beam of light is diffracted by the pattern and focused onto a transparency having a second array of discrete opaque regions spaced by a distance inversely proportional to the element spacing on the pattern. The focused light, spatially modulated by the transparency, is reimaged and projected in enlarged form onto a display screen.