Patent ID: 7277376

Claim:
An optical recording method for recording mark length-modulated information on a recording medium by applying a recording laser beam locally to the recording medium, characterized in that when the record mark length of one record mark is represented by nT (where T is the reference clock period, and n is a natural number of at least 2), in order to form the record mark length of nT, m pieces of recording pulses α i T (1≦i≦m) and m pieces of off-pulses β i T (1≦i≦m), represented by: α 1 T, β 1 T, α 2 T, β 2 T, . . . , α 1 T, β 1 T, . . . , α m T, β m T where m is a natural number representing a pulse dividing number, α i (1≦i≦m) is a real number of larger than 0, β i (1≦i≦m- 1 ) is a real number of larger than 0, and β m is a real number of at least 0), are used, and a recording laser beam having a writing power Pw i is applied within a time of α i T at any of 1≦i≦m, a recording laser beam having a bias power Pb i of Pb i <Pw i and Pb i <Pw i+1 , is applied within a time of β i T at any of 1≦i≦m- 1 , the front recording pulse α 1 T will rise as deviated for a time of dT top from the front position of the record mark having a length of nT (dT top being positive, when the rising is delayed from the front position of the record mark having a length of nT), with respect to at least two record marks, the pulse dividing number m is at least 2, and with respect to all record marks with m being at least 2, 2.5≦n/m, in a case where plural different record mark lengths are to be respectively formed by the same pulse dividing number m, α 1 and/or α m is changed to form such record mark lengths having different lengths respectively, provided that when the α 1 is changed, dT top and/or β 1 is also changed, and when the α m is changed, β m-1 and/or β m is also changed, and