| 摘要 |
PROBLEM TO BE SOLVED: To record/reproduce information on an optical recording medium having a plurality of specifications, to reduce the number of parts, to miniaturize it and to improve a temperature charactertstic. SOLUTION: This device is provided with optical means (22, 23, 25, 28) guiding beams from plural light sources 21, 31 to the optical recording medium 29 surface, a hologram 24 diffracting the beams of different wavelengths of at least two or above among the reflected beams from the optical recording medium 29 surface, the optical means (24, 26) separating the beam guided to the optical recording medium 29 surface from the reflected beams from the optical recording medium 29 surface and a photodetector 30 receiving the diffracted beams of plural different wavelengths from the hologram 24 and arranged so as to be separated from the light sources 21, 31. |
