Adaptive recording method and apparatus for high-density optical recording apparatus
AssigneeSamsung Electronics Co., Ltd.
InventorJin-gyo Seo
Life of this patent
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Abstract
An adaptive recording method and apparatus for optimizing power of a laser diode in high density optical recording. The mark size of input NRZI (Non Return to Zero Inversion) data is discriminated and the power of overwrite pulses is varied in accordance with the discriminated mark size, optimizing read power, peak power and bias power for overwrite pulses, to supply optimized pulses to the laser diode.
Claims8
An adaptive recording apparatus for controlling power of a laser diode, comprising:
- a discriminator which discriminates at least one of a mark size and a relationship between preceding and following spaces of input data and accordingly sets a power level;
- a generator which generates an overwrite pulse by controlling a waveform of an overwrite pulse in accordance with the input data;
- an adder which differentiates the power level data corresponding to the mark size output from the discriminator from reflected optical signal level data;
- a digital-analog converter (DAC) which converts the data output from the adder into an analog control current signal;
- and
- a laser diode driver which drives the laser diode by the analog control current signal supplied from the DAC.
An apparatus for overwrite recording of an input waveform on a recording disk, the input waveform having at least a mark, a preceding space and a following space, the apparatus comprising:
- a laser diode which irradiates the recording disk;
- a laser diode driver which applies power to the laser diode in response to a recording waveform and a power level signal;
- a photo diode which detects a reflected light from the recording disk;
- a recording waveform generator which generates the recording waveform based on the input waveform;
- a data discriminator which determines a recording power level based on at least one of the mark size and a relationship between the preceding space and the following space and outputs first power level data;
- a first circuit which compares a power of the reflected light with a reference level and outputs second power level data based on the comparison;
- and
- a second circuit which receives the first power level data and the second power level data and outputs the power level signal based on first and second power level data.
A method of adaptively controlling a power level of a laser diode in an apparatus for recording information on a recording medium, the method comprising:
- discriminating at least one of a mark size and a relationship between preceding and following spaces of input data and accordingly outputting first power level data to set the power level of the laser diode proportional to the mark size in a range including 3T and 14T;
- applying an optical signal from the laser diode to the recording medium at a power level corresponding to the first power level data;
- comparing a level of an optical signal, reflected from the recording medium during the applying of the optical signal to the recording medium, with a reference value and outputting a counted value based on the comparison;
- differentiating the first power level data from the counted value and outputting second power level data;
- and
- adjusting the power level of the laser diode to a power level corresponding to a sum of the first and second power level data.
Dependencies are inferred from the claim text.