| 摘要 |
PROBLEM TO BE SOLVED: To record or reproduce plural kinds of optical disks with the same optical pickup by providing two or above of reflection optical elements reflecting or transmitting luminous flux from a light emitting element toward an objective lens, and reflecting return light reflected by an information recording surface toward a light receiving element. SOLUTION: When a high density optical disk 9 is recorded/reproduced, a laser diode 1 is light emitted. Laser luminous flux 13 transmits at a characteristic of a dichroic coating 6a simultaneously with passing through a circular aperture 6b of a filter 6 to be made incident on the objective lens 5. The laser luminous flux 13 is converged on the information recording surface 10 of the high density optical disk 9 by the objective lens 5 so as to irradiate a read spot, and its reflected light is reflected toward a photodiode 8 by a half mirror 4, and is converged on the photodiode 8 by a condenser lens 12 to record/ reproduce the high density optical disk 9. Further, when a usual optical disk is recorded/reproduced, the laser diode 2 is light emitted. |
