发明名称 |
Front photo detector having no gain selection switch, optical pick-up including the front photo detector, and optical recording and/or playing apparatus including the front photo detector |
摘要 |
A front photo detector (FPD) of an optical pick-up for an optical recording and playing apparatus having no gain selection switch, a simplified configuration, an improved prevention of an abnormal operation due to an error in gain selection, and improved reliability. The front photo detector includes a photo diode unit, a current-voltage amplifying circuit, and a voltage amplifying unit. The photo diode unit outputs current proportional to the power of the light emitted from one of a plurality of laser diodes. The current-voltage amplifying circuit converts the current output from the photo diode unit into a voltage. The voltage amplifying circuit amplifies the voltage output from the current-voltage amplifying circuit by a predetermined gain.
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申请公布号 |
US2005025023(A1) |
申请公布日期 |
2005.02.03 |
申请号 |
US20040792917 |
申请日期 |
2004.03.05 |
申请人 |
SAMSUNG ELECTRONICS, CO., LTD. |
发明人 |
LEE HONG-KYU;KIM HEE-DONG;SEONG PYONG-YONG |
分类号 |
G11B7/125;G11B7/135;G11B31/02;H03F3/08;H03F3/68;H03G3/10;(IPC1-7):G11B31/00 |
主分类号 |
G11B7/125 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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