Method and device for recording an optical information carrier
AssigneeKoninklijke Philips Electronics N.V.
InventorJohannes Hendrik Spruit
Life of this patent
Estimating the term…
Abstract
A method is described for recording an optical information carrier, in which a mark representing recorded data is written in the information carrier at different writing speeds by a sequence of radiation pulses The last pulse of a sequence is followed by a period of reduced radiation power, the duration of which is inversely proportional to the writing speed.
Claims4
A method of recording marks representing data in an information layer of an optical information carrier comprising the steps of:
- moving the carrier with respect to a radiation beam so that linear writing speed varies during recording so that different portions of the same carrier are recorded at different linear writing speeds;
- writing a mark on the carrier by a sequence of one or more irradiation pulses, in which the last pulse in the sequence has a first power level;
- irradiation at a second power level lower than the first power level during a cooling period to allow the carrier to cool after writing the mark, the duration of the cooling period depending on the spot size of the radiation on the carrier and the duration of the cooling period varying depending on the linear writing speed;
- and
- after irradiating at the second power level, irradiating at a third power level higher than the second power level to provide an unmarked space between marks.
An optical recording device for recording data in the form of marks on an information layer of an information carrier, the device comprising:
- a radiation source providing a radiation beam for writing the marks;
- means for moving the information carrier with respect to the beam so that the linear writing speed varies with different portions of the same carrier are recorded at different linear writing speeds;
- a control unit for controlling the power of the radiation beam depending on the linear writing speed including:
- means for providing a sequence of one or more irradiation pulses having a first power level for writing a mark;
- means for providing irradiation at a second power level during a cooling period to allow the carrier to cool after writing the mark, the duration of the cooling period depending on a spot size of the radiation on the carrier and the duration of the cooling period varying depending on the linear writing speed;
- and
- means for after irradiation at the second power level, providing irradiation at a third power level to provide an unmarked apace between marks.
Dependencies are inferred from the claim text.