| 摘要 |
A pickup and a drive, in a small size, having a spherical aberration correction device capable of correcting various spherical aberration, and coma aberration and/or astigmatism with a low power consumption. A variable-focus lens actuator can correct spherical aberration such that a transparent deformation film warps into a parabolic shape when a magnetic field is applied thereto, thereby changing the light intensity distribution of transmitted light. Further, the variable-focus lens actuator can correct coma aberration and/or astigmatism by arbitrarily tilting the transparent film to change the proceeding direction of the transmitted light. |
