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:
Jan. 12, 1982
Filed:
Apr. 25, 1979
Ping Sheng, Princeton, NJ (US);
RCA Corporation, New York, NY (US);
Abstract
Recovery from a record of data recorded in an elongated information track, comprising depressed areas of various lengths alternating with non-depressed areas, is effected by an optical playback system. The playback system employs apparatus for focusing a laser source as a light spot on the information track. A light detector, responsive to light diffracted by the information track as relative motion is established between the light spot and the information track, is used in the playback apparatus to translate the depressions in the information track into frequency-modulated electrical signals. When the light spot size or depression spacing becomes comparable to the wavelength of the laser source, the signal strength at the detector output becomes dependent upon the polarization of the light spot incident on the information track. In the playback system, apparatus is provided for orienting the polarization of the light spot on the information track to enhance the signal strength of the detector output.