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:
Feb. 01, 2000
Filed:
Mar. 31, 1999
Applicant:
Inventors:
Pedro Gregorio, Verdun, Quebec, CA;
Vincent Hayward, Montreal, Quebec, CA;
Danny Grant, Montreal, Quebec, CA;
Assignee:
Other;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01B / ;
U.S. Cl.
CPC ...
356375 ; 356373 ;
Abstract
Positional sensors receive light that has been reflected off a pair of complementary geometric patterns carried by a supporting, displaceable carrier surface. The sensors view the patterns through viewing windows as the carrier surface is displaced laterally, presenting differing portions of the patterns to the sensors. The patterns are shaped to produce outputs which, when their difference value is extracted, provide output signals that are a measure of the displacement of the carrier surface and in which common mode errors are minimized.