Patent ID: 8824263

Claim:
An optical information recording device which records information on an optical information recording medium including N (where N is an integer of two or more) information layers, the N information layers each having a recording film of which a physical state changes as a result of a localized temperature change brought about by focusing a laser beam, the optical information recording device comprising: a light source which emits the laser beam; a recording pulse train generation unit which generates a recording pulse train for forming a recording mark on the recording film; a power setting unit which sets a power of each pulse in the recording pulse train; and a driving unit which drives the light source to emit the laser beam corresponding to the recording pulse train generated by the recording pulse train generation unit with the power set by the power setting unit, wherein a thickness DN of the recording film of an Nth information layer which is closest to a light entry surface of the optical information recording medium is smaller than a thickness DM of the recording film of an Mth information layer (where M is an integer such that N>M≧1), a reflectance RN from the Nth information layer is smaller than two times a reflectance RM from the Mth information layer, the recording pulse train includes at least one write pulse having a highest power, a bottom pulse which is formed, when there is a plurality of write pulses, between the write pulses, and a cooling pulse which is formed subsequent to a last write pulse, and when a power of the write pulse is taken as a peak power and a power of the bottom pulse is taken as a bottom power, the power setting unit sets the power of each pulse in the recording pulse train such that a peak power PwN of the Nth information layer, a bottom power PbN of the Nth information layer, a peak power PwM of the Mth information layer, and a bottom power PbM of the Mth information layer satisfy the following formula: PbN/PwN>PbM/PwM.