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:
Jun. 06, 2000
Filed:
Jul. 06, 1994
Applicant:
Inventors:
Peter G Borden, San Mateo, CA (US);
James B Stolz, Fremont, CA (US);
Assignee:
Fisher Pierce Co., Weymouth, MA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01N / ;
U.S. Cl.
CPC ...
250574 ; 35633911 ;
Abstract
A dark-field particle monitor and a method for reducing errors due to stray light in the particle monitor provides a particle monitor having (i) an optical element focussed on the laser beam for detecting particles and (ii) a filter for preferentially selecting light incident on said filter in a preferential direction. In one embodiments the filter is implemented by a narrow band filter having maximum transmission for light having a wavelength of the laser beam.