| 摘要 |
PURPOSE:To execute write with a high accuracy by controlling a voice coil motor by a phase difference of a moving pulse of a laser length measuring machine and a transmitter. CONSTITUTION:The titled system is constituted of a laser length measuring machine 4 for measuring a position of a voice coil motor loaded with a write head 3-1, a transmitter 7 for outputting a transmitting signal at every necessary track pitch of a master disk, and a PLL circuit 8, and also, constituted of a rotary encoder 12 for generating a clock of an integer multiple of the number of sectors of a master disk 1 to a spindle 2, and a sector write control circuit 11. The laser length measuring machine 4 measures a moving extent of the voice coil motor 3, outputs a pulse corresponding to the moving extent, a PLL circuit 8 detects a phase difference at every necessary track pitch by a pulse outputted by the transmitter 7, and a correction of a position of the voice coil motor 3 is controlled. In this way, write can be executed in a position of a high accuracy.
|
