| 摘要 |
The method involves rotating and adjusting setting an inclined glass plate (1) positioned between a first laser beam (9) with an astigmatic difference and a collimator lens (3) that can be set in rotation about an optical path of the first laser (2). The rotation and angle of inclination of the glass plate is adjusted to regulate a minimum difference between the focal positions on X and Y axes which are respectively parallel and perpendicular to the laser beam. When the difference between the positions of the focusing is minimum, the laser beam is directed onto the surface of an optical disk with a recording density such that the length of each bit is less than half the laser wavelength. |
