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:
Jun. 09, 1981

Filed:

Apr. 24, 1979
Applicant:
Inventors:

Tomio Yoshida, Katano, JP;

Yoshinobu Nakata, Ikoma, JP;

Shunji Harigae, Neyagawa, JP;

Toshio Sato, Moriguchi, JP;

Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
369112 ; 369122 ;
Abstract

An optical system for an optical data recording and reproducing apparatus such as an optical video disc apparatus comprising a diode laser light source, a condenser lens disposed adjacent to the diode laser, a cylindrical lens assembly arranged to exhibit different magnifications to light beams emitted by the diode laser in the direction perpendicular to a junction plane thereof and in the direction parallel to the junction plane, and a concentrating lens for constricting the resulting light beam into a light spot of a small size for projection on a recording medium. Recording of information is attained by the constricted light beam of a substantially circular cross-section with a high recording density at a low energy consumption. When reproducing the recorded information, the constricted beam is laterally enlarged in the transverse direction of the information recording track thereby to assure generation of a signal utilized for tracking control.


Find Patent Forward Citations

Loading…