OPTICAL INFORMATION MEDIUM MEASURING METHOD, OPTICAL INFORMATION MEDIUM, RECORDING DEVICE AND REPRODUCING DEVICE

摘要

Provided is an optical information medium measuring method wherein the modulation degree of an optical information medium which has a multilayer structure having a plurality of information layers is measured.  The method includes: a first step wherein the modulation degree of each layer of the optical information medium is measured by means of a measuring optical system; a second step wherein the interlayer thicknesses of the optical information medium are obtained; a third step wherein the reflectance of each layer of the optical information medium is obtained; and a fourth step wherein the modulation degree of each layer measured in the first step is converted into a modulation degree in the reference optical system, which is different from the measuring optical system, by using the interlayer thicknesses obtained in the second step and the reflectance value of each layer obtained in the third step.