公开(公告)号：US06894955B1

公开(公告)日：2005-05-17

申请号：US09675059

申请日：2000-09-29

申请人： Yoshitaka Shimoda ,  Masayoshi Yoshida ,  Shinichi Nagahara ,  Tsuyoshi Hasebe ,  Motoji Nakamura

发明人： Yoshitaka Shimoda ,  Masayoshi Yoshida ,  Shinichi Nagahara ,  Tsuyoshi Hasebe ,  Motoji Nakamura

IPC分类号： G11B7/085 ,  G11B7/09 ,  G11B7/095 ,  G11B7/135 ,  G11B7/18

CPC分类号： G11B7/1353 ,  G11B7/08517 ,  G11B7/08529 ,  G11B7/08541 ,  G11B7/0903 ,  G11B7/094 ,  G11B7/0953 ,  G11B7/0956

摘要： There are provided an information write device and an information read device enabling to generate highly accurate contrast signals. When a main light spot Pc is located at the center of the a groove G, the light spot Pc and sub light spots Psa, Psb are each adapted to radiate a disc DSC such that the sub light spots Psa, Psb radiate positions displaced from the center of the land L. The reflected beams of light from the disc DSC caused by the radiation with the light spots Pc, Psa, Psb are detected to generate push-pull signals each corresponding to the light spots Pc, Psa, Psb, respectively, in accordance with each of the detected signals. Furthermore, a signal to be obtained by amplifying an addition signal, given by adding the push-pull signals each corresponding to the sub light spots Psa, Psb, with a predetermined amplification factor K/n, and a push-pull signal corresponding to the main light spot Pc are added to thereby generate a contrast signal.

摘要翻译： 提供了一种能够产生高精度对比度信号的信息写入装置和信息读取装置。 当主光斑Pc位于凹槽G的中心时，光斑Pc和次光斑Psa，Psb各自适于辐射盘DSC，使得副光斑Psa，Psb辐射位置从 检测由具有光斑Pc，Psa，Psb的辐射引起的来自光盘DSC的反射光束，以产生分别对应于光点Pc，Psa，Psb的推挽信号， 根据每个检测到的信号。 此外，通过以预定的放大系数K / n加上每个与子光点Psa，Psb相对应的推挽信号给出的相加信号的放大而获得的信号和对应于 添加主光点Pc，从而生成对比度信号。