发明名称 |
Optical pick-up head, optical information apparatus, and optical information reproducing method |
摘要 |
An optical information apparatus of the present invention includes: an optical pick-up head including: a light source; a diffraction unit; a condensing unit; a beam splitter; a photodetector; and a tracking error signal generator. An optical recording medium has tracks arranged substantially at a constant pitch. An average of a pitch is tp. When a main beam is placed on the track, a first sub-beam and a second sub-beam are placed between the tracks. The tracking error signal generator performs a differential arithmetic operation with respect to signals output from a light-receiving portion receiving the main beam to generate a first push-pull signal, performs a differential arithmetic operation with respect to signals output from the light-receiving portions receiving the first sub-beam and the second sub-beam to generate a second push-pull signal, and performs a differential arithmetic operation with respect to the first push-pull signal and the second push-pull signal to generate a tracking error signal, in a case where an amplitude of the first push-pull signal obtained at the pitch tp is fluctuated when the light beam is scanned in a direction orthogonal to the tracks of the optical recording medium.
|
申请公布号 |
US7463561(B2) |
申请公布日期 |
2008.12.09 |
申请号 |
US20070789078 |
申请日期 |
2007.04.23 |
申请人 |
PANASONIC CORPORATION |
发明人 |
KADOWAKI SHIN-ICHI;SANO KOUSEI;ARAI AKIHIRO;YASUDA KATSUHIKO;KAMEI TOMOTADA;YAMAMOTO HIROAKI;YAMASAKI FUMITOMO |
分类号 |
G11B7/00;G11B7/09;G11B7/005;G11B7/085;G11B7/095;G11B7/125;G11B7/13;G11B7/131;G11B7/135;G11B7/1353;G11B7/1392 |
主分类号 |
G11B7/00 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|