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:
Apr. 29, 1997
Filed:
Jul. 10, 1995
Sergey V Broude, Newton Centre, MA (US);
Nicholas Allen, Bedford, MA (US);
Abdu Boudour, West Newton, MA (US);
Eric Chase, Carlisle, MA (US);
Carl Johnson, Tewksbury, MA (US);
Pascal Miller, North Chelmsford, MA (US);
Jay Ormsby, Salem, MA (US);
QC Optics, Inc., Burlington, MA (US);
Abstract
An improved optical inspection system for detecting flaws on a diffractive surface containing surface patterns includes: an ultraviolet illumination means for illuminating a region on the diffractive surface to generate a scattered intensity distribution in response to either a flaw or a surface pattern; means for detecting the intensity level of the scattered intensity distribution at a plurality of locations about the diffractive surface; means for establishing a minimum detected intensity level; means, responsive to the minimum detected intensity level, for indicating the absence of a flaw on the illuminated region of the diffractive surface when the minimum detected intensity level is below a threshold intensity level and for indicating the presence of a flaw on the illuminated region of the diffractive surface when the minimum detected intensity level exceeds the threshold intensity level; and means for moving the diffractive surface to generate a scan pattern on the diffractive surface to inspect the entire surface.