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:
Nov. 03, 1981
Filed:
May. 10, 1979
Applicant:
Inventors:
Yoshito Tsunoda, Mitaka, JP;
Kimio Tatsuno, Kokubunji, JP;
Toshimitsu Miyauchi, Hachioji, JP;
Kunio Aiki, Hachioji, JP;
Ryoichi Ito, Hachioji, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
369 45 ; 369 44 ; 369 93 ; 369111 ; 369122 ; 346 / ; 3581285 ; 250201 ; 250578 ;
Abstract
An optical head comprising a semiconductor laser array which is used as a light source, and an optical system which guides laser beams from the array to a predetermined recording medium. The beam from one lasing point of the array is modulated by predetermined information and is used as a recording beam, while the beam from another lasing point is continuously oscillated and is used as a playback beam.