Optical recording method and optical recording medium

摘要

An optical recording method for recording mark length-modulated information on a recording medium by using a plurality of recording mark lengths. The optical recording method comprises the steps of: when a time length of one recording mark is denoted nT (T is a reference clock period equal to or less than 25 ns, and n is a natural number equal to or more than 2), (i) dividing the time length of the recording mark nT into eta₁T, alpha₁T, beta₁T, alpha₂T, beta₂T, . . . , alpha_iT, beta_iT, . . . , alpha_mT, beta_mT, eta₂T in that order (m is a pulse division number; Sigma_i(alpha_i+beta_i)+eta₁+eta₂=n; alpha_i (1<=i<=m) is a real number > 0; beta _i (1<=i<=m-1) is a real number > 0; beta _m is a real number >=0; and eta₁ is a real number of -2<=eta₁<=2 AND eta₂ is a real number of -2<=eta₂<=2); radiating recording light with a recording power Pw_i in a time duration of alpha_iT (1<=i<=m), and radiating recording light with a bias power Pb_i in a time duration of beta_iT (1<=i<=m), the bias power being Pb_ii and Pb_ii+1; and (ii) changing m, alpha_i, beta_i, eta₁, eta₂, Pw_i and Pb_i according to n of the time length nT of the recording mark; wherein the pulse division number m is 2 or more for the time duration of at least one recording mark and meets n/m>=1.25 for the time length of all the recording marks.