| 摘要 |
PURPOSE:To precisely adjust a position by adjusting the position on the basis of a signal, amplified by a non-linear amplifier. CONSTITUTION:A device is installed on a table holder 11, and provided with a table 13 to drive a PUH 1, mounted on a pickup head PUH table 12, vertically (arrow mark 100 direction) and forward.backward (arrow mark 101 direction), a motor 14 to drive the table 13 forward.backward, the motor 15 to drive it vertically, and a PD holder 16, which is fixed at the table 13 and holds a photodiode PD 2. Besides, an amplifying means 17 to amplify an electric signal, transmitted from the PD 2, an operating means 18 to obtain the above-mentioned radial error Rer and a tangential error Ter from the amplified signal, the non- linear amplifier 19 to amplify the signal, based on the obtained operation result, and a feedback means 20 to drive the motors 14, 15 according to the signal, amplified by the said non-linear amplifier 19, are provided. Thus, the position adjusting can be performed automatically and precisely. |
