MAGNETO-OPTICAL DATA MEMORY DISK HAVING SMOOTH REFLECTOR LAYER OF HIGH CONDUCTIVITY

摘要

PROBLEM TO BE SOLVED: To increase the memory density of an optical recording medium. SOLUTION: The optical data memory medium of an air incidence type has a substrate, a reflector layer, a magneto-optical recording layer and a protective layer. The reflector layer has at least one among an electrical conductivity exceeding about 5.0×10 (Ω.cm) an RMS surface roughness below about 1.0 nm in measurement by an atom force microscope and a refractive index below about 0.5 at a read-out wavelength.