Magneto-optical recording medium and recording apparatus therefor

A recording apparatus, comprising:

• a magneto-optical recording medium having a transparent substrate provided on a partial or entire surface thereof with spiral or concentric guide grooves and signal-recording regions located between the spiral or concentric guide grooves,
• an objective lens disposed in an opposed relation to said magneto-optical recording medium;
• and
• a light-radiating means adapted to radiate a write laser beam in the form of pulses for recording an information signal, onto said magneto-optical recording medium through said objective lens, said laser beam having a duty factor of not more than 50%,
• wherein said recording apparatus is so constructed as to satisfy the following conditions (1) to (4):
• 0.431(.lambda./NA)<W<(0.8TP-0.143)(.lambda./NA) (1)
• 0.62(.lambda./NA)<TP<0.80(.lambda./NA) (2)
• 0.084(.lambda./n.sub.s)<d<0.18(.lambda./n.sub.s) (3)
• and
• d/(.lambda./n.sub.s).gtoreq.0.48-0.53TP/(.lambda./NA) (4)
• where W represents a width of the guide grooves;
• .lambda. represents a wavelength (.mu.m) of the read light for reproducing the information signal stored on, the magneto-optical recording medium;
• NA represents a numerical aperture of the objective lens;
• TP represents a track pitch (.mu.m) of the guide grooves;
• d represents a depth (nm) of the guide grooves;
• and n.sub.s represents a refractive index of the transparent substrate.