Patent ID: 7773483

Claim:
An information recording apparatus for recording information by injecting energy on a recording medium and forming marks of different physical characteristics with the unrecorded part, comprising: an encoder for converting information into a recording data sequence; a discriminator for discriminating marks of the length of a natural number k times of the unit L of pitch of variation in the symbol length according to the quotient d obtained by and the remainder r remaining after dividing k by an integer constant n of 2 or more with reference to the mark length in the recording data sequence; an energy generator for generating the energy necessary for recording; and a driver for driving the energy generator in such a way that the shortest time interval between the points of change in the ratio of energy injected per unit time during the mark-forming period which is not shorter than ½ of the length of time corresponding to the symbol length L according to the result of discrimination by the discriminator, wherein the discriminator controls the energy generator in such a way that the top part of the mark-forming period may have mutually different waveforms of the top part of the mark-forming period chosen by r according to the remainder r remaining after dividing k+p of the mark length k*L(a≦k≦a+n−1) by n for any mark a*L or more and (a+n−1)*L or less by setting the range chosen for the mark length according to the rule of conversion in case that the mark length is between a times of L or more and b times of L or less and by choosing any optional integer constant for p, wherein the discriminator controls the energy generator in such a way that the mark-forming period target length may have succeeding part of mark-forming period formed by the repetition of positive pulses of d times according to a recording pulse having a time cycle corresponding to the length n*L on the recording medium following a n number of different top parts of mark-forming period chosen by r according to the quotient d obtained and the remainder r remained after dividing k+p of the mark length k*L(a+n≦k≦b) by n for any marks (a+n)*L or more and b*L or less, and wherein when the mark-forming period target length is a*L or more and (a+n−1)*L and the mark-forming period target length is (a+n)*L or more and b*L or less, the waveform of the top part of mark-forming periods for the same remainder r is respectively different according to whether the mark-forming period target length is a*L or more and (a+n−1)*L or less, or (a+n)*L or more and b*L or less.