发明名称 |
Tracking error detection device |
摘要 |
A tracking error detecting apparatus converts photoelectric current obtained by a photo detector into voltage signals at current/voltage conversion circuits, and adds the voltage signals to generate two signal series at adders. The two signal series are digitalized at analog to digital converters, are subjected to interpolation processing at interpolation filters and have their zero cross points detected by zero cross point detector circuits respectively. A phase difference between the zero cross points of the two signal series is detected by a phase difference detector circuit, and the phase difference is subjected to band restriction by a low pass filter, thereby to obtain a tracking error signal. The tracking error detecting apparatus is capable of coping with speed doubling of an optical recording/reproducing apparatus and density enhancing of an optical recording medium with a small size and at low cost.
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申请公布号 |
US6741533(B1) |
申请公布日期 |
2004.05.25 |
申请号 |
US20010830676 |
申请日期 |
2001.08.06 |
申请人 |
MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD. |
发明人 |
HIRATSUKA TAKASHIGE;MARUKAWA SHOJI;OKAMOTO TOSHINORI |
分类号 |
G11B7/09;(IPC1-7):G11B7/00 |
主分类号 |
G11B7/09 |
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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