Patent ID: 7218593

Claim:
A recording strategy generating method for an optical information recording medium on which information relative to a mark and a space, the space being an interval between two marks, is recorded by a PWM modulation method, the mark lasting for a time period nT, where n represents a natural number and T represents a basic clock cycle under recording conditions, and wherein: the space is recorded by irradiating an optical beam at irradiation power Pe; the mark is recorded by irradiating m pulses, each consisting of an optical beam at irradiation power of two levels Pw and Pb, where Pw>Pe>Pb; an average period of the pulse irradiation for every mark is n/m; relations n=n 1 =2m are fulfilled where the number n is even; relations n=n 2 =2m+1 are fulfilled where the number n is odd; a first pulse of the irradiation power Pw rises after elapse of time T d1 from a start time of a logical mark; a last pulse, which is the m-th pulse of the irradiation power Pb finishes earlier than an end time of the logical mark by time T d2 ; and parameters normalized by the basic clock cycle T, namely, T d1 /T and T d2 /T, of a recording strategy for all the marks of n>=4 are made constant independent of scanning speed, and when said method comprises the steps of: pre-formatting a piece of information that represents the parameters T d1 /T and T d2 /T for structuring the recording strategy on the optical information recording medium; reading the information representing the parameters T d1 /T and T d2 /T for structuring the recording strategy, the information being encoded and pre-formatted on the optical information recording medium in advance of a recording operation; converting the information representing the parameters T d1 /T and T d2 /T into real number information by decoding and converting using a conversion table; and generating the recording strategy for the multi-pulse, wherein periods T d1 and T d2 , which fulfill the recording conditions, are specified based on the real number information obtained by converting the parameters T d1 /T and T d2 /T, wherein: T d1 is a first time period, T d2 is a second time period, T d1 /T is a rising time of the first pulse, and T d2 /T is a rising time of the last pulse.