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:
May. 21, 1991
Filed:
Dec. 08, 1989
Applicant:
Inventor:
Victor D Loewen, San Jose, CA (US);
Assignee:
Hewlett-Packard Company, Palo Alto, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01D / ;
U.S. Cl.
CPC ...
25023114 ; 25023116 ; 2502 / ;
Abstract
Disclosed are apparatus and methods for transducing mechanical movement into electrical signals indicative of the movement. The apparatus is an improved optical encoder of the type having a source of light, a code wheel for modulating the light according to movement of the object whose position is being measured and a photo detector for receiving the modulated light. The code wheel modulates the light from the light source into spiral-shaped beams of light separated by columns of spiral-shaped dark areas. Photo detectors are oriented to receive the modulated light.