Patent ID: 7292525
Filing Date: 2007-11-06
Classification: G11B

Abstract:
1. An optical information recording method in which information signals are recorded on an optical information recording medium provided with N information recording layers (where N is an integer of 2 or more) each having a recording layer that is subject to a change in its physical state due to local temperature changes caused by a focused light beam, the method comprising: a step of selecting a recording pulse control rule, from a plurality of recording pulse control rules for which waveforms of a recording pulse are determined respectively, in correspondence with an information recording layer to be recorded, and a step of recording information signals on the recording layer by modulating an intensity of the light beam in correspondence with the recording pulse that is determined by the selected recording pulse control rule; wherein of the N information recording layers, if a layer farthest from the side of light incidence is regarded as a first information recording layer and layers progressively closer to the side of light incidence are regarded as second to N-th information recording layers, then the recording pulse control rule that is selected when recording to the second to the N-th information recording layers corresponds to a recording pulse waveform that, if employed for recording to information recording layers having identical thermal properties with the first information recording layer, results in a steeper temperature change in the recording layer during cooling than the recording pulse control rule that is selected when recording to the first information recording layer.