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:
Jun. 29, 1982
Filed:
May. 14, 1980
Herman W Willemsen, Nepean, CA;
Northern Telecom Limited, Montreal, CA;
Abstract
In a scanning head for an optical disc system, a light beam from a laser is transmitted through a monomode optical fiber and then focussed on a record carrying surface of an optical disc by a converging lens. The end of the fiber can be reoriented within orthogonal planes perpendicular to the plane of the record carrying surface by transducers so as to correct for tracking and timing errors. The laser diode can function both as an emitter and, in an external cavity mode, as a detector of light reflected from the disc. Drive to the transducers is dependent on tracking and speed error signals generated from the detected light. For tracking and speed error compensation, only lens fiber end, and, optionally, a collimating lens, which are of negligible weight, need be moved rather than the entire scanning head. This provides a simple structure having a high frequency response and low power consumption.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile