Invention Grant
- Patent Title: Optical head apparatus and optical information recording and reproduction apparatus
- Patent Title (中): 光头装置和光信息记录和再现装置
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Application No.: US11620094Application Date: 2007-01-05
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Publication No.: US07782540B2Publication Date: 2010-08-24
- Inventor: Yasuhiro Tanaka , Tomohiko Sasano , Michihiro Yamagata , Daisuke Ogata
- Applicant: Yasuhiro Tanaka , Tomohiko Sasano , Michihiro Yamagata , Daisuke Ogata
- Applicant Address: JP Osaka
- Assignee: Panasonic Corporation
- Current Assignee: Panasonic Corporation
- Current Assignee Address: JP Osaka
- Agency: RatnerPrestia
- Main IPC: G02B13/22
- IPC: G02B13/22 ; G02B9/12 ; G02B9/14 ; G02B9/04 ; G11B7/135

Abstract:
Disclosed is an optical head apparatus comprising: a light source; a collimating means of converting a beam of light emitted from the light source into a substantially parallel beam of light; a focusing means of focusing the light onto an information medium surface; a beam splitting means of splitting the beam of light modulated by the information medium; and a light receiving means of receiving the light modulated by the information medium, wherein a lens having a negative power and a lens having a positive power are arranged in this order as viewed from the collimating means side between the collimating means and the focusing means, and at least either one of the lenses is moved along an optical axis to correct spherical aberration occurring on the information medium surface, and wherein the distance from the lens having the positive power to the focusing means is set substantially equal to the focal length of the lens having the positive power.
Public/Granted literature
- US20070109948A1 OPTICAL HEAD APPARATUS AND OPTICAL INFORMATION RECORDING AND REPRODUCTION APPARATUS Public/Granted day:2007-05-17
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