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. 10, 1998
Filed:
Dec. 10, 1996
Sony Corporation, Tokyo, JP;
Abstract
An optical pick-up apparatus includes a light source, an objective lens, a beam splitter, a detector, a first optical compensating device and a second optical compensating device. The objective lens converges a light beam emitted from the light source at one point on an optical axis. The beam splitter separates the light beam emitted from the light source from a returning light reflected on an optical disc. The detector detects the returning light separated from the light beam emitted from the light source. The first optical compensating device has a convex aspherical surface represented by X.alpha.R.sup.4 and is located on an optical path where the light beam is emitted from the light source. The second optical compensating device has a concave aspherical surface represented by +.alpha.R.sup.4 and is located on an optical path where the light beam is emitted from the light source.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile