Patent ID: 8509046
Filing Date: 2013-08-13
Classification: G11B

Abstract:
1. An optical information recording method by which marks are formed by irradiation with a laser beam corresponding to a recording pulse sequence modulated between a plurality of power levels and information is recorded based on edge positions of the marks and spaces between the marks, on an optical information recording medium provided with N (N is an integer equal to or greater than 2) information layers each having a recording layer in which variations in a physical state are caused by local temperature variations caused by convergence of a laser beam, the optical information recording method comprising: a step of selecting control parameters of the recording pulse sequence for forming the marks on the basis of combinations of a mark length of the mark, a first space length of a first space immediately before the mark, and a second space length of a second space immediately after the mark; and a step of recording the marks by the recording pulse sequence determined by the selected control parameters, wherein in the step of selecting control parameters of the recording pulse sequence, the first space length is classified into m types (m is an integer), and the second space length is classified into n types (n is an integer), at least either of the m and the n being equal to or greater than 2; the control parameters include (m×n) control parameters each corresponding to a combination of the first space length and the second space length; and an absolute value of a difference between two predetermined control parameters from among the (m×n) control parameters selected during recording on a second information layer located on an incidence side of the laser beam with respect to a predetermined first information layer from among the N information layers is equal to or greater than an absolute value of a difference between two predetermined control parameters from among the (m×n) control parameters selected during recording on the first information layer.