| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical pickup device having satisfactory optical characteristics using a semiconductor laser unit of two wavelengths. <P>SOLUTION: The optical pickup device comprises the semiconductor laser unit of two wavelengths for a CD and for a DVD, a collimator lens and an object lens. Coma aberrations generated according to configurations of the semiconductor laser unit 2 of two wavelengths and an optical system are classified into a coma aberration caused by the image height on the CD side, a coma aberration caused by the image height on the DVD side, a coma aberration on the CD side due to the object lens and a coma aberration caused by the image height on the DVD side due to the object lens. The semiconductor laser unit is disposed by determining the positions of a light source for the CD and a light source for the DVD so that the sum total of these coma aberrations is made to be 0. Thereby, the coma aberration producing amount as the optical pickup device is made to be 0 as a whole for satisfactory optical characteristics. <P>COPYRIGHT: (C)2004,JPO |
