| 摘要 |
PURPOSE:To miniaturize the optical head device, to facilitate production and to improve reliability. CONSTITUTION:The luminous flux emitted from a semiconductor laser 1 is disposed so as to be made incident on a polarizing light separating semipermeable film 101 at an angle inclined at 22.5 deg. therewith. This polarizing light separating semipermeable film 101 and a polarized light separating film 102 are formed to attain 54 deg. angle and the refractive index of a medium to transmit light is 1.7. The light emitted from the semiconductor laser 1 is reflected by the polarizing light separating semipermeable film 101 and is condensed onto a recording medium by an objective lens 2. The light reflected by the recording medium returns backward the forward path. The light is transmitted to the polarizing light separating semipermeable film 101 and is separated by the polarized light separating film 102 to P polarized light and S polarize light. The light is detected by a first photodetector 4 and a second photodetector 5, by which a servo signal and reproduced signal are obtd. |
