| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a high reliability optical pickup device for the optical pickup device, built into a disc device to drive an optical disc, in which the laser beam power to create a laser spot on the optical disc is not attenuated, the status of light-emitting quantity for a semiconductor laser element is monitored accurately, and a change of environmental conditions, such as uneveness of reflection factor and a transparency rate due to a reflection film and temperature or humidity in not influenced. <P>SOLUTION: The optical pickup device, in which the laser beam emitted from a semiconductor laser element 1a, is irradiated on a recording medium D via a shaping prism 5 so that recording or reproducing information can be performed. A part of a marginal light L1 of the laser beam, irradiating on the shaping prism 5, is irradiated on an external wall 5c of the shaping prism and its reflecting light is induced to a light-sensitive element 6. The light emission output of the semiconductor laser element 1a is controlled, based on the output signal of the above light-sensitive element. <P>COPYRIGHT: (C)2004,JPO |
