公开(公告)号：US4747089A

公开(公告)日：1988-05-24

申请号：US939614

申请日：1986-12-09

申请人： Naoya Eguchi ,  Mikio Sigiki ,  Hitoshi Okada

发明人： Naoya Eguchi ,  Mikio Sigiki ,  Hitoshi Okada

IPC分类号： G11B7/085 ,  G11B7/09 ,  G11B7/00 ,  G11B20/22

CPC分类号： G11B7/0941 ,  G11B7/0909

摘要： A focusing control method and apparatus employing a photodetector for generating a focusing error signal, a tracking error signal and an RF signal, and a closed loop focusing servo circuit responsive to the focusing error signal applied thereto for focusing a light spot in position on an optical disc. The focusing error signal is detected synchronously with the tracking error signal to produce a first periodic function signal. The focusing error signal is detected synchronously with the RF signal to produce a second periodic function signal. The tracking error signal is converted into a sin-wave signal having a predetermined amplitude. The RF signal is converted into a cos-wave signal having a predetermined amplitude. The first periodic function signal is multiplied by the cos-wave signal to produce a first component signal. The second periodic function signal is multiplied by the sin-wave signal to produce a second component signal. The first and second component signals are added to produce a composed disturbance signal. The composed disturbance signal is subtracted from the focusing error signal applied to the focusing servo circuit, thereby canceling a disturbance superimposed on the focusing error signal applied to the focusing servo circuit.

摘要翻译： 一种聚焦控制方法和装置，其采用光检测器来产生聚焦误差信号，跟踪误差信号和RF信号，以及闭环聚焦伺服电路，响应于施加于其上的聚焦误差信号，将光点聚焦在光学上的位置上 光盘。 与跟踪误差信号同步地检测聚焦误差信号以产生第一周期性函数信号。 与RF信号同步地检测聚焦误差信号以产生第二周期函数信号。 跟踪误差信号被转换成具有预定幅度的正弦波信号。 RF信号被转换成具有预定幅度的cos波信号。 第一周期功能信号乘以cos波信号以产生第一分量信号。 第二周期函数信号乘以sin波信号以产生第二分量信号。 添加第一和第二分量信号以产生合成干扰信号。 从施加到聚焦伺服电路的聚焦误差信号中减去组合的干扰信号，从而消除叠加在施加到聚焦伺服电路的聚焦误差信号上的干扰。