| 摘要 |
<P>PROBLEM TO BE SOLVED: To realize good recording and/or reproducing by using a common objective lens corresponding to three different wavelengths to secure working distance and prevent decline of light intensity. <P>SOLUTION: The optical pick up comprises a first emission section for emitting an optical beam with first wavelength, a second emission section for emitting an optical beam with second wavelength, a third emission section for emitting an optical beam with third wavelength, an objective lens 33 for condensing the optical beams with the first to third wavelengths emitted from the first to third emission sections on a signal recording surface of the optical disk, an optical-path combining means 34 for combining the optical path of the optical beam with the first wavelength emitted from the first emission section and the optical paths of the optical beams with the second and third wavelengths emitted from the second and third emission sections, and an aberration correcting means 35 which is set on the optical paths of the optical beams with the second and third wavelengths. <P>COPYRIGHT: (C)2008,JPO&INPIT |
