OPTICAL RECORDING MEDIUM, SUBSTRATE FOR OPTICAL RECORDING MEDIUM AND OPTICAL DISK DEVICE

摘要

In an optical recording medium employing an intermediate address method, a pit width W of an address pit is set to satisfy the relationship: W = k . Tp / ( lambda / NA) Ä0.40≤k≤0.68Ü with respect to a laser wavelength lambda and a numerical aperture NA of an objective lens of an optical head of an optical disk device being used, and a track pitch Tp of the recording medium. Alternatively, an optical disk device is provided with a first address demodulating circuit for demodulating address information using a sum signal of electric signals output from a photodetector divided into two parts in a track direction and a second address demodulating circuit for demodulating address information using a difference signal of the electric signals, and an address is detected based on information obtained from the first and second address demodulating circuits. Thus, in reproduction of the optical recording medium employing the intermediate address method, compatibility of the recording medium and the optical disk device being used can be enhanced, and a reproduction margin in demodulating address information can be increased, thereby achieving high-accuracy address detection.