METHOD FOR EVALUATING CHARACTERISTICS OF MULTILAYER OPTICAL RECORDING MEDIUM

摘要

A multilayer optical recording medium having three or more information recording layers is irradiated with a laser beam, and a first signal obtained from the reflected laser beam is subjected to a frequency filter. A second signal obtained by filtration through a high-pass filter is used to evaluate the characteristics of the multilayer optical recording medium. Inthismanner, eveninamultilayeroptical recording medium having three or more information recording layers, the influence of the variation of the thickness and material of the information recording layers and the influence of the variation of the thickness of a spacer layer can be clearly determined and evaluated.