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:
Feb. 08, 2000
Filed:
Dec. 24, 1997
Atsushi Tajiri, Osaka-fu, JP;
Takenori Goto, Moriguchi, JP;
Yasuaki Inoue, Nagaokakyo, JP;
Kazushi Mori, Hirakata, JP;
Minoru Sawada, Yawata, JP;
Akira Ibaraki, Hirakata, JP;
Sanyo Electric Co., Ltd., Moriguchi, JP;
Abstract
An optical pickup device has a case constructed by joining a lower frame member and an upper frame member. A semiconductor laser device, a three-beam generating diffraction grating, a transmission type holographic optical element, and a reflecting mirror are arranged in the lower frame member. A lead frame is arranged in the lower frame member. The semiconductor laser device is arranged on the lead frame through a heat sink, to emit laser light in a horizontal direction. A photodiode and the lead frame are arranged in the upper frame member. The photodiode has a light receiving surface parallel to the direction of light emission from the semiconductor laser device, and is mounted on the lead frame. The laser light emitted from the semiconductor laser device passes through the three-beam generating diffraction grating and the transmission type holographic optical element, and is then bent upward and introduced into an optical recording medium. Returned light reflected from a recording surface of the optical recording medium is changed in a direction parallel to the direction of light emission from the semiconductor laser device, passes through the transmission type holographic optical element and the three-beam generating diffraction grating again, is then changed vertically upward by the reflecting mirror, and is incident on the photodiode.