| 摘要 |
PURPOSE:To suppress the reduction of a confirming reproducing signal by providing the two divided light receiving element, detecting a track dislocation from the output of a differential amplifier and making variable the light quantity of the beam for confirming and reproducing in accordance with the detected track signal. CONSTITUTION:A two divided light receiving element 14 light-receives a beam for confirming and reproducing reflected from an optical disk, the difference in the detecting signal of light-receiving elements 14a and 14b is obtained by a differential amplifier 15 and thus, the track dislocation signal of the beam is detected. A gain controller 16 controls the gain of the track signal controlled by an LD driving circuit 17 and outputted from the amplifier 15. Namely, when the light quantity of the beam is increased, the gain is lowered, and when the light quantity is reduced, the gain is raised, and thus, the track dislocation quantity and the track signal quantity are corresponded. By variable-adjusting the light quantity of the beam corresponding to the track dislocation, the reduction due to the track dislocation of the confirming reproducing signal is suppressed and the stable conforming reproducing information can be obtained. |
