| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical head integrally having laser light sources having a plurality of wavelengths, so configured that stable operation and price reduction can be attained by making design of an automatic power control circuit easy and the optical head is made to conform to even when it has a plurality of laser light sources, and to provide an optical disk device. <P>SOLUTION: The optical head is provided with a light source outputting a laser beam, an objective lens condensing and emitting the incident laser beam toward an optical disk and receiving the returned laser beam reflected by the optical disk, a beam splitter disposed on an optical axis between the light source and the objective lens, a half wave plate disposed on the optical axis between the light source and the beam splitter, controlling the polarization state of the optical beam from the light source and capable of adjusting the ratio of monitoring light and main light going straight which are branched by the beam splitter, and the automatic power control circuit receiving the monitoring light branched by the beam splitter and controlling beam output power of the light source. <P>COPYRIGHT: (C)2007,JPO&INPIT |
