| 摘要 |
PURPOSE:To improve the recording accuracy by focusing the laser beams, which are divided into two halves from an identical optical source, upon a slit having a preset positional relationship so that the two intermediate image beams are simultaneously and separately focused upon a recording medium through a polarizing prism or the like. CONSTITUTION:The laser beam from its source 6 is divided by a half-mirror 9 into two halves, one of which is modulated into a signal beam in accordance with the recording signals so that it is focused upon the slit S1 of a member 15 of the focal plane of a lens 16 and the other of which becomes a track-servo beam by the preset modulation so that it is focused upon the slit S2 of a member 25 or the focal plane of a lens 26, thus forming two intermediate images. In accordance with the relative poitional relationships of the slits S1 and S2, the two intermediate images are simultaneously focused in a manner not to overlap on a recording medium D by the actions of the lenses 16 and 26, a polarizing prism 17 and a condensing lens 20. A partial evaporation of the record due to the temperature change in case the recording operations are performed at different timings witn the use of different optical images thereby to make it possible to accomplish the highly accurate optical recording operations. |
