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. 07, 2000
Filed:
Dec. 02, 1997
Takao Rokutan, Higashimurayama, JP;
Olympus Optical Company, Ltd., Tokyo, JP;
Abstract
An apparatus for recording and reproducing optical information on and from an optical record medium such as optical card including an optical device having semiconductor lasers 1, 2, diffraction gratings 6, 10a, 10b and objective lens 3 for projecting a recording light beam, two verifying light beams and plural reproducing light beams onto plural adjacent tracks on the optical card 4, and a photo-detector 16 having two verifying light receiving sections 27c and 27e which receive the verifying light beams reflected by the optical card and at least one leak light receiving section 28 which receives only the undesired recording light beams reflected from the optical card 4. Output signals from the verifying light receiving sections 27c and 27e are corrected by an output signal from the leak light receiving section 28. The recorded information can be verified accurately in accordance with either one of the corrected output signals from the verifying light receiving sections 27c and 27e depending upon a moving direction of the optical card with respect to the light spots.