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. 16, 1990
Filed:
Oct. 21, 1988
Robert G Knollenberg, Boulder, CO (US);
Particle Measuring Systems, Inc., Boulder, CO (US);
Abstract
A surface analysis system and method are disclosed for determining particle contamination and/or defects on or below a surface of material. Laser beams having different polarizations are directed to the surface to be analyzed and light scattered from particle contamination and/or defects on or below the surface is collected and detected to provide electrical signals representative thereof. The electrical signals are then processed to provide an output indicative of sensed contamination and/or defects. In the embodiment particularly shown and described, a pair of polarized laser beams, one of which is a 'P' polarized laser beam and the other of which is a 'S' polarized laser beam, are separately directed to a monitoring region so that the beams impinge at a common point on the surface to be analyzed. The scattered light is then collected and split into two components depending upon whether scattered from the 'P' polarized laser beam or the 'S' polarized laser beam and each component is separately detected, after which the electrical outputs are processed to provide the desired indication.