OPTICAL INFORMATION RECORDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To provide a disk which is an optical disk for executing recording at both of lands and grooves, is nearly equal in the carrier levels of regenerative signals in the lands and the grooves, allows tracking by a 3-beam system, is good in tracking servo characteristic and decreases crosstalks. SOLUTION: A groove depth (GD), the wavelength (λ) of a recording and reproducing light source and the refractive index (n) of a substrate are so set as to attain the relation of formula I and the width (WL) of the lands and the depth (WG) of the grooves attain the relation of formula II, where the formula I: λ/6.5n