| 摘要 |
PURPOSE:To obtain a stable optical pick-up device at a low cost by providing an optical conducting path, which has a branching optical path, and an optical path selecting means between a laser and a polarizing beam splitter, providing an electro- optical crystal between the splitter and a recording medium and impressing an electric field to an electrode. CONSTITUTION:It is independently executed in the respective optical paths that an incoming light is divided into the optical paths in a right side and a left side by a branching optical path 15 of an optical conducting path 14 and polarization is executed concerning respective right and left lights by an electro-optical crystal 16. During this operation, in correspondence to the dislocation quantity of a spot position to be caused by a track error signal, the electric field is impressed to an electrode part 17 of the crystal 16. Thus, the incoming light of one side part is polarized and the adjustment of the spot position is executed. Since the selection of the branching optical path and the control of the impressing electric field to the electrode part is simultaneously processed, the polarization of the light can be executed independently by each optical path and spot moving quantity for tracking servo can be widely decreased. Then, driving can be executed at a low voltage and an actuator for objective lens drive is eliminated. Thus, the compact device can be obtained at the low cost. |
