Abstract: A method of writing a mark to an optical disc includes receiving data to be written and generating a control signal for a laser pulse having a melt period that transitions to a growth period wherein the melt period is characterized by a melt power and the growth period is characterized by a growth power.

Abstract: A system and method are disclosed for providing a gain control signal for a multilevel read signal. In one embodiment, maximum automatic gain control marks are periodically inserted amongst a series of data fields. The automatic gain control marks include a series of high level marks such that the maximum signal detected in the interior portion of each maximum automatic gain control mark is not reduced by intersymbol interference. Minimum automatic gain control marks are also periodically inserted amongst a series of data fields. The automatic gain control marks include a series of high level marks such that the maximum signal detected in the interior portion of each minimum automatic gain control mark is not reduced by intersymbol interference. In another embodiment, multilevel signals are encoded to facilitate automatic gain control. The effect of a plurality of candidate merge symbols on the residual running total power associated with a current data block is determined.

Abstract: A method of writing a mark to an optical disc includes receiving data to be written and generating a control signal for a laser pulse having a melt period that transitions to a growth period wherein the melt period is characterized by a melt power and the growth period is characterized by a growth power.

Abstract: A system and method are disclosed for reading a multilevel signal from an optical disc. The method includes reading a raw analog data signal from a disc using an optical detector and adjusting the amplitude of the raw analog data signal. A timing signal is recovered from the amplitude adjusted analog data signal and correction is made for amplitude modulation of the raw analog data signal by processing the raw analog data signal and the timing signal.

Abstract: Methods and systems for write compensation for optimizing the performance of a data storage or communication channel are disclosed. In one embodiment, a method comprises determining channel sensitivity to modifications in write signal parameters, detecting systematic errors in a read signal recovered from data written with a first set of write parameters, and adjusting the write signal parameters by an amount determined from the channel sensitivity such that the systematic errors are reduced when data are written with the adjusted write parameters.

Abstract: A system and method are disclosed for compensating during a data writing process for a transformation of input data by an optical disc data storage channel. A write strategy matrix is derived that maps a plurality of input sequences to a plurality of write strategy parameters. The input sequences each include a plurality of input data elements. When an input sequence is received, the write strategy matrix is used to determine in selected write strategy parameter that corresponds to the input sequence.

Abstract: A system and method are disclosed for providing a gain control signal for a multilevel read signal. In one embodiment, maximum automatic gain control marks are periodically inserted amongst a series of data fields. The automatic gain control marks include a series of high level marks such that the maximum signal detected in the interior portion of each maximum automatic gain control mark is not reduced by intersymbol interference. Minimum automatic gain control marks are also periodically inserted amongst a series of data fields. The automatic gain control marks include a series of high level marks such that the maximum signal detected in the interior portion of each minimum automatic gain control mark is not reduced by intersymbol interference. In another embodiment, multilevel signals are encoded to facilitate automatic gain control. The effect of a plurality of candidate merge symbols on the residual running total power associated with a current data block is determined.

Abstract: A system and method are disclosed for reading a multilevel signal from an optical disc. The method includes reading a raw analog data signal from a disc using an optical detector and adjusting the amplitude of the raw analog data signal. A timing signal is recovered from the amplitude adjusted analog data signal and correction is made for amplitude modulation of the raw analog data signal by processing the raw analog data signal and the timing signal.

Abstract: A system and method are disclosed for recording information on a phase change medium is disclosed. The method includes irradiating a region of the phase change medium with a first dose of laser energy. A first portion of the region is irradiated with a second dose of laser energy in a manner that causes the first portion of the region irradiated with the second dose of laser energy to be in a different state than a second portion of the region that is not irradiated by the second dose of laser energy.

Abstract: A system and method are disclosed for reading a multilevel signal from an optical disc. The method includes reading a raw analog data signal from a disc using an optical detector and adjusting the amplitude of the raw analog data signal. A timing signal is recovered from the amplitude adjusted analog data signal and correction is made for amplitude modulation of the raw analog data signal by processing the raw analog data signal and the timing signal.

Abstract: Methods and systems for write compensation for optimizing the performance of a data storage or communication channel are disclosed. In one embodiment, a method comprises determining channel sensitivity to modifications in write signal parameters, detecting systematic errors in a read signal recovered from data written with a first set of write parameters, and adjusting the write signal parameters by an amount determined from the channel sensitivity such that the systematic errors are reduced when data are written with the adjusted write parameters.

Abstract: A system and method are disclosed for reading a multilevel signal from an optical disc. The method includes reading a raw analog data signal from a disc using an optical detector and adjusting the amplitude of the raw analog data signal. A timing signal is recovered from the amplitude adjusted analog data signal and correction is made for amplitude modulation of the raw analog data signal by processing the raw analog data signal and the timing signal.