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. 04, 1997
Filed:
Jan. 11, 1996
Shigeru Ohuchida, Machida, JP;
Hiroyoshi Funato, Chigasaki, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
An optical head which records data onto an optical data recording medium and reproduces the data therefrom includes a laser light source, a collimator lens, an objective lens, a light splitting device arranged between the laser light source and the objective lens, for splitting the emitted light from the laser light and a reflected light from the optical data recording medium. A diffraction grating is provided to which only the reflected light split at the light splitting device is incident to, and which leads the reflected light split at the optical element onto a photo-detector. Thereby, an optical head of high effectiveness in utilization of light and low cost can be obtained.