| 摘要 |
An optical pickup apparatus for irradiating a light beam on an optical recording medium (8) for recording or reproduction, including a light source (1), an objective lens (7), a nonpolarization beam splitter (10), a photodetector (9), and a 1/4 wavelength plate (6). The objective lens (7) focuses the light beam radiated from the light source (1) on to the recording layer of the optical recording medium (8). The nonpolarization beam splitter (10) is disposed between the objective lens (7) and the light source (1) and separates the light beam emitted from the light source (1) and the light beam reflected by the recording layer of the optical recording medium (8). The photodetector (9) receives the beam of light reflected by the recording layer of the optical recording medium (8) which has been separated by the nonpolarization beam splitter (10) and deflected 90 DEG in optical path. The 1/4 wavelength plate (6) is disposed on the path of emission of the light beam emitted from the light source (1) between the nonpolarization beam splitter and the optical recording medium (8). <IMAGE> |
