Patent ID: 6936325

Claim:
An optical recording medium having at least a recording layer and a light transmitting layer formed on a substrate, characterized in that the recording layer is made of an organic material for absorbing an incident light of wavelength of from 360 nm to 460 nm, and inducing physical change or chemical change to vary its refractive index, the light transmitting layer is 10 μm to 177 μm in thickness, the relation between absorption coefficient (k) and pyrolysis temperature Tdec of the organic material is 950 (° C.)<(Tdec (° C.)−20)/k<4100° C., and the absorption coefficient “k” is k>0.0; a carrier (C) /noise (N) ratio of C/N>43 dB; wherein the organic material is a dye or a pigment selected from the group consisting of azo, merocyanines, hemicyanines, strepto cyanines, zero cyanines, enamine, hydrazone, coumarines and phthalocyanines; and wherein recording and reproducing is made with an optical system with a numerical aperture of an objective lens of the optical pickup of 0.80 or more, by employing a bluelight source of wavelength of about 360 nm to about 460 nm.