A comparison of various readout techniques in magneto-optic recording

The application of confocal, non-confocal, and magnetooptic phase contrast readout techniques to magnetooptic recording is described. Experimental investigations using a scanning laser microscope indicate that the introduction of a confocal aperture into the detector space can sharpen the system step response, reduce intersymbol interference, and provide an in-built focus error signal. It is concluded that the use of magnetooptic phase contrast provides a further alternative to conventional polar Kerr readout and introduces the possibility of particularly simple replay optics