Title:
OPTICAL INFORMATION REPRODUCTION DEVICE, OPTICAL INFORMATION RECORDING DEVICE, OPTICAL INFORMATION REPRODUCTION METHOD, AND OPTICAL INFORMATION RECORDING METHOD
Document Type and Number:
WIPO Patent Application WO/2011/105068
Kind Code:
A1
Abstract:
In order to accurately operate tilt servo even when gap servo is operated with the gap being set small, a light focusing unit (102) generates near-field light and focuses laser light onto an optical disk (1), a light amount detection unit (104) detects the light amount of feedback light from a region in which the near-field light is generated, a gap control unit (105) controls the gap between the light focusing unit (102) and the optical disk (1) on the basis of the light amount of the feedback light, a tilt calculation unit (106) calculates the amount of tilt between the light focusing unit (102) and the optical disk (1) on the basis of the light amount of the feedback light while the gap is being controlled, a tilt error signal generation unit (107) generates a tilt error signal that is a signal obtained by removing a fluctuation component of the feedback light due to the decentering of the optical disk (1) from the amount of tilt, and a tilt control unit (108) controls the tilt between the light focusing unit (102) and the optical disk (1) on the basis of the tilt error signal.
Inventors:
NARUMI, Kenji (())
鳴海 建治 (())
鳴海 建治 (())
Application Number:
JP2011/001019
Publication Date:
September 01, 2011
Filing Date:
February 23, 2011
Export Citation:
Assignee:
PANASONIC CORPORATION (1006, Oaza Kadoma Kadoma-sh, Osaka 01, 〒5718501, JP)
パナソニック株式会社 (〒01 大阪府門真市大字門真１００６番地 Osaka, 〒5718501, JP)
NARUMI, Kenji (())
パナソニック株式会社 (〒01 大阪府門真市大字門真１００６番地 Osaka, 〒5718501, JP)
NARUMI, Kenji (())
International Classes:
G11B7/095; G11B7/135
Attorney, Agent or Firm:
KOTANI, Etsuji et al. (Osaka Nakanoshima Building 2nd Floor, 2-2, Nakanoshima 2-chome,,Kita-ku, Osaka-sh, Osaka 05, 〒5300005, JP)
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Claims:
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