| 摘要 |
<p>An optical disc device uses an optical disc (6) capable of super-resolution reproduction, and includes a semiconductor laser (1), a laser driving circuit (21) that supplies a driving current to the semiconductor laser, a light receiving element (8) that detects return light from the optical disc (6) and obtains reproduction signal of recording data of the optical disc (6), and a light emission amount control means (22) that controls a light emission amount of the semiconductor laser (1) by the laser driving circuit (21) so as to keep a peak intensity of a focused light spot formed on an information recording layer of the optical disc 6 to be greater than or equal to a peak intensity at which a super-resolution effect is obtained. The light emission amount control means (22) controls a light emission amount of the semiconductor laser (1) by the laser driving circuit (21) based on a decrease rate D of a peak intensity of a focused light spot on an information recording layer of the optical disc (1) determined by an assumed disc tilt and a comatic aberration according to a thickness of a light transmitting layer of the optical disc (1), and a lower limit value Pld_L of a light emission amount at which a predetermined reproduction performance is obtained.</p> |
