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:
Oct. 20, 1987
Filed:
Mar. 25, 1985
Gary M Giddings, Laguna Hills, CA (US);
Discovision Associates, Costa Mesa, CA (US);
Abstract
A method and apparatus for rapidly moving a reading beam of light radially relative to a rotating record disc, to impinge on a selected target track on the disc and recover information recorded on it. The apparatus first radially translates an optical system that directs the beam onto the disc at a relatively high speed until it is within a prescribed radial distance of the target track. Thereafter, an element of the optical system is controllably deflected such that the beam moves incrementally across a prescribed plurality of tracks during each disc revolution, until reaching the target track. The information recorded on each track includes a unique addres signal, and movement of the beam relative to the disc is controlled according to the difference between the respective addresses of the track currently being scanned and the target track. If the apparatus fails to properly recover a track address signal, it estimates the address of the track currently being scanned, and updates its control of the beam's radial movement based on that estimate.