| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical pickup device and an optical system capable of effectively correcting the variation of a spherical aberration generated due to the mode hop of a semiconductor laser. SOLUTION: Since a means (negative lens 4) for correcting the variation of a spherical aberration generated in an objective lens 3 is arranged between a light source 11 to be the semiconductor laser and the objective lens 3, the variation of the spherical aberration of the lends 3 due to the variation of oscillation wavelength can be effectively suppressed even when the variation of oscillation wavelength is generated due to the generation of a mode hop phenomenon or the like in the laser 11. Even when a change of the refractive index of the lens 3 is generated in accordance with a change in ambient temperature or humidity, the variation of the spherical aberration of the lens 3 which is generated due to the change can be effectively suppressed. |
