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:
Jan. 02, 1996

Filed:

Feb. 17, 1994
Applicant:
Inventors:

Takeshi Shimano, Hachioji, JP;

Kenchi Ito, Hachioji, JP;

Yooji Maruyama, Iruma, JP;

Hiroyuki Awano, Nagareyama, JP;

Assignee:

Hitachi, Ltd., Tokyo, JP;

Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
369 4412 ; 369109 ; 369112 ; 369 4414 ;
Abstract

The optical head is arranged such that a semiconductor laser and a photodetector are formed via a buffer layer on the same substrate; and an opening portion is formed in the substrate under the semiconductor laser and the photodetector. This optical head is further arranged by that the opening portion is filled with a first transparent layer; a diffraction grating is formed on a lower surface of the first transparent layer; a second transparent layer is stacked on a lower surface of the first transparent layer; and a condenser lens is formed on a lower surface of the transparent layer. In this optical head, laser light emitted from the semiconductor laser is penetrated through the substrate, the first transparent layer, the diffraction grating, and the second transparent layer, and condensed toward a place just under the condenser lens by the condenser lens, thereby forming a light spot on an optical storage medium positioned apart from the condenser lens, whereas reflection light reflected from the optical storage medium is penetrated through the condenser lens and the second transparent layer, diffracted by the diffraction grating toward a light receiving plane of the photodetector, and further penetrated through the first transparent layer to be received by the photodetector.


Find Patent Forward Citations

Loading…