| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method of controlling a divided light quantity ratio by which an optimal divided light quantity ratio can be obtained for coping with light of multiwavelength of two or more wavelengths, and to provide an optical pickup system and an optical recording and reproducing apparatus using the method. <P>SOLUTION: Corresponding to the light of a plurality of wavelengths incident on a diffraction optical element, the divided light quantity ratio of 0-th diffracted light and that of primary diffracted light are controlled to respective predetermined values. As the diffraction optical element, a diffraction optical element by liquid crystal or a junction hologram element, etc. is used. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
