OPTICAL PICKUP AND RECORDING/REPRODUCING DEVICE

摘要

An optical pickup (12) comprising a laser light source (17), a polarization beam splitter (20), and an object lens (15) for condensing a laser beam passed through the polarization beam splitter onto the recording layer (100a) of an optical recording medium (100) to form a beam spot, wherein a polarization control means (19) consisting of a single or a plurality of liquid crystal panels is disposed between the laser light source and the polarization beam splitter so as to change the polarization of a laser beam passing liquid crystal panels according to a voltage applied to a liquid crystal panel (19a), whereby it is possible to control the light quantity of a laser beam advancing toward an object lens without using a mechanical means and set the light intensity of the beam spot to a level according to a position from the surface of the recording layer and its sensitivity.