发明名称 Focus error detecting device and optical pickup apparatus provided with the same
摘要 A focus error detecting device which can realize stable focus servo without causing a deterioration in the quality of a signal, is provided. The focus error detecting device outputs a reflected light detection result by an optical recording medium to control a distance between an objective lens and the optical recording medium. With respect to the focus error detecting device, between the objective lens and two split light-receiving segments, is provided a hologram element for bending an optical path so that part of light reflected by the optical recording medium enters the two split light-receiving segments, and splitting a light beam of reflected light entering the two split light-receiving segments into a plurality of parts.
申请公布号 US2006018212(A1) 申请公布日期 2006.01.26
申请号 US20050176938 申请日期 2005.07.08
申请人 SHARP KABUSHIKI KAISHA 发明人 TSUCHIDA KAZUHIRO;FUKUMOTO SATORU;MASUI KATSUSHIGE;MATSUBARA KAZUNORI;SAKAI KEIJI
分类号 G11B7/00 主分类号 G11B7/00
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