| 摘要 |
PURPOSE:To provide an optical head in which light from a semiconductor laser and light reflected and returned from an optical disk is exactly separated. CONSTITUTION:The optical head is provided with a semiconductor laser 1, collimator lens 2 for converting the light emitted from the semiconductor laser 1 into parallel light, and objective lens 6 for converging this parallel light onto an optical disk 8. A semiconductor substrate 4 for reflecting the parallel light is arranged on an optical path between the collimator lens 2 and the objective lens 4. At the semiconductor substrate 4, a photodetector is formed and on its surface, a polarizing film is formed for reflecting P-polarized light at a prescribed ratio (such as 80%, for example.) A 1/4 wavelength plate is arranged on an optical path between the semiconductor substrate 4 and the objective lens 6. A beam splitter 3 for guiding the returned light from the optical disk 8 to an information reproducing optical system is provided on an optical path between the colimator lens 2 and the semiconductor substrate 4. |
