ACCESS METHOD FOR OPTICAL DISK AND OPTICAL DISK DEVICE

PROBLEM TO BE SOLVED: To record a program of a long time by recording a desired video signal and audio signal with respect to an optical disk whose diameter and light transmission layer are made specific values with an optical system whose working distance and numerical aperture are specified to make the feature of the optical disk utilizable effectively. SOLUTION: Data by a video signal and an audio signal in which the shortest bit length or the shortest mark length is not larger than 0.3 [μm] are recorded with respect to an optical disk whose diameter is 120 [mm] and light transmission layer is 10-177 [μm] in thickness with an optical system whose working area is not larger than 560 [μm] and numerial aperture is not smaller than 0.78 [μm]. Capacity of the extent of 8 [GB] is secured by recording the data in this manner and the program of the extent of about three hours can be recorded at the maximum. Then, the program of a long time can be recorded by making the data recordable in high density while utilizing the feature of the optical disk effectively.