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. 30, 1993
Filed:
Feb. 25, 1992
Kenji Shimozawa, Sagamihara, JP;
TEAC Corporation, , JP;
Abstract
An optical head apparatus applicable to an optical disc apparatus having an optical disc comprises a light source emitting a light beam, and an optical system transmitting the light beam emitted from the light source onto a surface of the optical disc and transmitting a light beam reflected on the surface of the optical disc to a first optical detector and to a second optical detector. The optical system includes a beam splitter splitting the light beam reflected by the surface of the optical disc into a first light beam traveling toward the first optical detector and a second light beam traveling toward the second optical detector, and a transparent member fixed to the beam splitter, through which the second light beam passes and causing astigmatic difference in the second light beam.