| 摘要 |
PURPOSE:To provide an optical pickup capable of avoiding the complexity of an optical system and detecting a signal with a high S/N ratio. CONSTITUTION:This device comprises a light source 20 emitting a polarized light beam, an objective lens 23, a beam splitter 22' composed of a first and a second prisms 22a, 22b arranged on an optical path from the light source 20 to a recording medium 24 and a detecting means 28 for detecting a reflected light beam from the recording medium 24, a light beam from the light source 20 is reflected through the first prism 22a and introduced to the recording medium 24. By transmitting the reflected light beam from the relevant recording medium through the first and the second prisms 22a, 22b, the light beam projected on the recording medium 24 is separated from the reflected light beam and the second prism 22b is composed of a uniaxial crystal dividing the reflected light beam into a first and a second light beam whose polarization directions are mutually orthogonal. The detector means 28 comprises a first and a second detectors detecting the first and the second light beams, respectively, and a means for differentiating the detected outputs of the first and the second detectors and obtaining an information signal. |
