1993 Volume 17 Issue 2 Pages 161-164
The track pitch of magneto-optical disks with metal guiding layers was reduced to less than the laser spot size by suppressing crosstalk. The recorded domain width was effectively confined by the width of the recording region in which the guiding layer was spirally removed. Improvement of the CNR was achieved by using the structure of substrate/enhancing layer/guiding layer/interference layer/recording layer. The total thickness of the enhancing and interference layers was adjusted in order to increase the Kerr effect enhancement, and a CNR of 47.1dB at 3.73 MHz was obtained for a track pitch of 1.0μm. Low crosstalk values of less than -28.8 dB and -26.2 dB were achieved at 1.0 MHz for track pitches of 1.0 and 0.9μm, respectively, with a conventional optical head having an objective lens of 0.53 NA and a 780-nm laser.
