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:
Mar. 26, 1991
Filed:
Feb. 03, 1989
Applicant:
Inventor:
Ray M Dolby, San Francisco, CA (US);
Assignee:
Other;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B / ; G11B / ; G11B / ;
U.S. Cl.
CPC ...
369 4432 ; 369128 ; 369133 ; 369215 ; 369258 ;
Abstract
Means for reducing the effects of vertical perturbations of a phonograph disc surface resulting from disc and/or playback system mechanical imperfections. Such imperfections are compensated by closed loop and/or open loop means wherein the deviations of the record path are detected and employed to minimize the effects of the mechanical imperfections.