| 摘要 |
PURPOSE:To reduce the size by fixing a spherical objective lens in the hole of a magnetic material. CONSTITUTION:The laser beam emitted from a semiconductor laser 41 consists of S waves and is reflected by a polarizing beam splitter (PBS) 42, goes through an objective lens 36 and is converged onto a magneto-optical film 61a of a magneto-optical disk 61. P wave components are generated in the beam reflected from the film 61a by a Kerr effect. The reflected beam is made incident on a photodetector 45 through the objective lens 36, the PBS 42 and a semitransparent reflecting film 47. A portion of the light beam is reflected by the film 47, reflected by a total reflection mirror and is made incident on a photodetector 46. By this arrangement, a recording and a reproducing are performed. The approximately spherical objective lens 36 is fixed by adhesive on a conical hole 37 which is formed on a magnetic material cover 35 that has a coil 38 generating a magnetic field being applied to the disk 61 so that the focal length is reduced and the size is made small. |
