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:
Sep. 24, 1996
Filed:
Sep. 19, 1994
Sou Ishika, Kanagawa-ken, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
An optical head device for irradiating a light beam onto a recording medium to optically reproduce information recorded on the recording medium, the device includes a light source for generating a light beam to project onto the recording medium, a detector for detecting the light beam reflected from the recording medium, and an optical system for leading the light beam from the light source to the recording medium along a first optical axis and leading the light beam reflected from the recording medium along the first optical axis to the detector. The device further includes a half mirror arranged between the optical system and the recording medium, for reflecting a part of the light beam led to the recording medium toward the optical system to lead the part of the light beam onto the detector. The half mirror is tilted at a prescribed angle against the first optical axis to lead the part of the light beam reflected along a second optical axis differ from the first optical axis to the detector.