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. 13, 1990
Filed:
Aug. 02, 1988
Applicant:
Inventors:
Shuichi Onayama, Osaka, JP;
Kazuhiko Nosaka, Osaka, JP;
Assignee:
NEC Home Electronics Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02B / ;
U.S. Cl.
CPC ...
350-373 ; 350-37 ; 350-372 ;
Abstract
An optical pickup for picking up signals from an optical disk comprises a hologram to split a laser beam emitted from a laser light source into one 0th order diffraction light beam and two 1st order diffraction light beams, and also to diffract return light beams reflected from the optical disk with two grating areas formed on one surface thereof. The diffracted light beams from the hologram are detected by a 6-piece-divided photodetector. The number of parts included in the system has been greatly reduced.