| 摘要 |
PURPOSE: To obtain an optical disk capable of a high density recording and a disk reproducing method and a device to reproduce the optical disk. CONSTITUTION: The optical disk 2 reads information on an information medium face by reflected light of a laser beam projected to the information medium face on which the information has been recorded. The information to be recorded is recorded on the information medium face as pits. Plural kinds of the pits (e.g. shown in figure (A)) are in existence corresponding to information to be recorded, where length of the pits in the circumferential direction or the radial direction of the optical disk 2 differs from each other. The depth of each pit is formed to be depth of phase being nearly (1+2n)/λ(n is an integer), where λ is a wavelength of a laser beam. Thus, a difference from the reflected luminous quantity between the pits of different length is maximized. The optical disk reproducing device reads information of plural pits based on luminous intensity including a 1st diffracted light from pits. Higher density recording more than a conventional disk by 30% or more is attained. |
