| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical disk device capable of suppressing drops of the S/N ratio of a reproduced signal when the objective lens of a high NA is used. <P>SOLUTION: This optical disk device is provided with a light source, an objective lens system 10 which includes at least one objective lens for converging a laser beam emitted from the light source on an optical disk medium, and a reproducing optical system 40 for guiding the reflected light from an optical disk medium Dc through the objective lens system 10 to a detector 43. The objective lens system 10 is characterized in that in the wavelength area of the light source, an S polarization transmittance seen from the objective lens system 10 is substantially larger than a P polarization transmittance, when the polarized direction of the light source is substantially parallel to the recording track Tr of the optical disk medium Dc. <P>COPYRIGHT: (C)2004,JPO |
