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. 20, 1986
Filed:
Nov. 23, 1983
Applicant:
Inventor:
Charles W Reno, Cherry Hill Township, Camden County, NJ (US);
Assignee:
RCA Corporation, Princeton, NJ (US);
Primary Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
369 45 ; 250201 ;
Abstract
Focus error due to drift from a specified value of the pointing angle of a focus laser light beam with respect to the reflective surface of an optical disc is self-compensated by employing two light beams derived from the same focus laser that have a substantially constant angular displacement therebetween. Any change due to drift in the specified value of the pointing angle of one light beam is accompanied by a substantially equal and opposite change due to drift in the specified value of the pointing angle of the other light beam.