Center aperture detection on magnetically induced super resolution magneto-optical disks

Abstract

A vector diffraction model has been applied to analyze CAD readout of MSR disks. Numerical results indicate that the read power is optimized with an aperture of the same size as the recorded mark. CNR decreases as recorded density increases even by using optimized aperture. CAD MSR disks applications are limited by the aperture-to-spot ratio of 34%. Also, CNR decreases as the track pitch becomes narrower. The vector model presents a higher sensitivity than the scalar model in analyzing the optical readout characteristics of sub-mu m disk structure and 'below-diffraction-limit' aperture of the readout spot.