| 摘要 |
PROBLEM TO BE SOLVED: To make possible applying them to plural recording media at a low cost by switching one side position between a laser light source and a coupling lens with a moving mechanism. SOLUTION: The moving mechanism 7 driving at least one side between the laser light source 4 and the coupling lens 5 in the optical axial direction is provided. Then, the moving mechanism 7 is driven according to thickness of a transparent substrate existing between an objective lens 6 and the recording surfaces 2b, 2b' of the recording media 2, 2', and at least one side position between the laser light source 4 and the coupling lens 5 is switched. Thus, they are complied with plural recording media with different thickness of the transparent substrate existing between the objective lens 6 and the recording surface. Further, a low cost becomes possible also. |
