| 摘要 |
PURPOSE:To improve the characteristics of both recording and reproducing by providing two kinds of the light sources of different wavelengths as a recording light source and a reproducing light source. CONSTITUTION:For instance, the wavelength of the He Ne laser 1 to be the recording light source is 633nm, and the output of the laser 1 is adjusted so as to be 7mW on the recording layer of a disk (D), and the wavelength of the outgoing beam of a low-noise self-oscillating semiconductor laser 6 is 780nm, and the output of the laser 6 on the recording layer of the disk (D) is adjusted so as to be 0.5mW. The recording light source 1 emits a beam of a wavelength region favorable to the recording, and the reproducing light source 6 emits the beam of the wavelength favorable to the reproduction. By providing these two kinds of the light sources, both the recording and the reproduction can be executed without causing any inconvenience with each other. |
