| 摘要 |
In an optical head device, a light emission source for emitting a plurality of laser beams with different wavelengths and an optical system including an objective lens and a collimator are provided. With respect to the optical system to be used in common for a plurality of optical recording media of different kinds, the RIM intensity is set to be not less than 0.1 and the magnification is set in the range of 4 to 6. With these conditions applied to the RIM intensity and the magnification of the optical system, light utilization efficiency at the time of CD recording is ensured, while preventing this from adversely affecting DVD reproduction or recording and while ensuring a beam spot quality.
|
