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.

Date of Patent:
Sep. 21, 1999

Filed:

Aug. 12, 1997
Applicant:
Inventor:

Hiroyuki Ishihara, Tokyo, JP;

Assignee:

NEC Corporation, Tokyo, JP;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
369112 ; 369 4437 ; 369121 ;
Abstract

There is provided an optical pick-up apparatus including (a) a plurality of light emitting devices emitting laser beams having different wavelengths, (b) inclined reflective surfaces by the same number as that of the light emitting devices for reflecting the laser beams, (c) the same number of optical systems for image-formation as that of the light emitting devices, each of the optical systems being disposed just above each of the inclined reflective surfaces, each of the optical systems focusing the laser beams reflected at the inclined reflective surfaces on an optical disk medium and transmitting therethrough the laser beams reflected from the optical disk medium, and (d) a light receiving device receivable all of the reflected laser beams. In accordance with the above mentioned optical pick-up apparatus, all laser beams emitted from the light emitting devices and reflected from the optical disc medium are received in the common light receiving device. Hence, all data stored in the laser beams can be processed by a single light receiving device, which ensures the reduction in the number of parts for constituting an optical pick-up apparatus and hence the reduction in fabrication costs. In addition, it is also ensured to fabricate an optical pick-up apparatus in a smaller size.


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