| 摘要 |
<p>PURPOSE:To obtain a magneto-optical head device which is small in size, low in price and has a good signal-to-noise ratio during a reproducing. CONSTITUTION:75% of the outgoing light from a semiconductor laser 1 passes a polarizing hologram optical element 49 and is converged on a magneto-optical disk 5 by an objective lens 4. The reflected light from the disk 5 is diffracted to realize 20% main polarizing component and 81% magneto-optical signal component by the element 49. The +1st order diffracted light of the element 49 is directly received by photodetectors 50 and 51 and is used to detect focus error signals and track error signals. On the other hand, the -1st order diffracted light of the element 49 is made incident on polarizing beam splitters 52 and 53 and separated into transmissive and reflective lights which are t45 degree direction polarizing components. These lights are respectively received by the light receiving sections corresponding to the photodetectors 50 and 51 and magneto-optical signals are detected from the output difference of the light receiving sections corrsponding to the + or -45 degree direction polarization components by a differential detection method.</p> |
