| 摘要 |
<p>In an optical pickup, the sum signal -VMAIN of the light receiving sections A, B, C and D of a main photo diode is applied to an inversion amplifier Amp9, and the sum signal VMAIN is applied to a data processor section and a mirror signal arithmetic section. An inversion amplifier Amp10, on the side of sub photo diodes, receives the sum of the sum signal -VSUB E and a corrected signal C*VMAIN which is obtained by adjusting the sum signal VMAIN of the main photo diode with a variable resistor VR1. The output of the inversion amplifier Amp10 becomes a regular sub beam receiving signal VSUB which is obtained by subtracting a correcting signal whose voltage is equal to the main beam leakage signal from the sub photo diode sum signal -VSUB E. The regular sub beam receiving signal is applied to the mirror signal arithmetic section. <IMAGE></p> |
