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US 2010/0246350 A1Published application
Optical disc device and laser power control method
AssigneePanasonic Corporation
InventorKenji Fujiune
Life of this patent
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Abstract
An optical disk apparatus according to the present invention generates a divided clock signal by dividing a recording clock signal, and based on the divided clock signal, determines a test emission pattern for test recording which is used for controlling the power of a light beam that is output from an emission section. When the linear velocity at recording changes, the division ratio is adjusted in a direction of reducing a change in frequency of the divided clock signal. In an optical disk apparatus which performs laser power control by conducting a test emission with multipulses in a test area, a good detection accuracy of a multi-pulse average value can be maintained even at high x-speeds.
Claims25
An optical disk apparatus comprising:
- an emission section for outputting a light beam to be radiated on an information medium;
- a current adjustment section for detecting a light amount of the light beam and adjusting a current to be supplied to the emission section;
- a recording clock generation section for generating a recording clock signal to serve as a reference at data recording;
- a frequency division section for dividing the recording clock signal to generate a divided clock signal;
- a recording pattern calculation section for setting a data recording emission pattern based on the recording clock signal, the data recording emission pattern being for recording data;
- a test pattern calculation section for setting a test emission pattern for test recording based on the divided clock signal, the test emission pattern being for controlling a power of the light beam which is output from the emission section;
- and
- a current output section for supplying a current to the emission section based on an emission pattern which is selected from between the data recording emission pattern and the test emission pattern and on a current value which is calculated by the current adjustment section, wherein,
- when a linear velocity at recording changes, the frequency division section adjusts a division ratio in a direction of reducing a change in frequency of the divided clock signal.
6 more elements
An optical disk apparatus comprising:
- an emission section for outputting a light beam to be radiated on an information medium;
- a current adjustment section for detecting a light amount of the light beam and adjusting a current to be supplied to the emission section;
- a recording clock generation section for generating a recording clock signal to serve as a reference at data recording;
- a test clock generation section for generating a test clock signal to be used at test recording;
- a recording pattern calculation section for setting a data recording emission pattern based on the recording clock signal, the data recording emission pattern being for recording data;
- a test pattern calculation section for setting a test emission pattern for test recording based on the test clock signal, the test emission pattern being for controlling a power of the light beam which is output from the emission section;
- and
- a current output section for supplying a current to the emission section based on an emission pattern which is selected from between the data recording emission pattern and the test emission pattern and on a current value which is calculated by the current adjustment section, wherein,
- the test clock generation section generates the test clock signal so as to have a constant frequency irrespectively of a linear velocity at recording.
6 more elements
A laser power controlling method comprising:
- a recording clock generation step of generating a recording clock signal to serve as a reference at data recording;
- a frequency division step of dividing the recording clock signal to generate a divided clock signal;
- a recording pattern calculation step of setting a data recording emission pattern based on the recording clock signal, the data recording emission pattern being for recording data;
- a test pattern calculation step of setting a test emission pattern for test recording based on the divided clock signal, the test emission pattern being for controlling a power of a light beam;
- and
- a current outputting step of supplying a current to an emission section based on an emission pattern which is selected from between the data recording emission pattern and the test emission pattern, wherein,
- the frequency division step includes a step of adjusting a division ratio in a direction of reducing a change in frequency of the divided clock signal when a linear velocity at recording changes.
4 more elements
A laser power controlling method comprising:
- a recording clock generation step of generating a recording clock signal to serve as a reference at data recording;
- a test clock generation step of generating a test clock signal to be used at test recording;
- a recording pattern calculation step of setting a data recording emission pattern based on the recording clock signal, the data recording emission pattern being for recording data;
- a test pattern calculation step of setting a test emission pattern for test recording based on the test clock signal, the test emission pattern being for controlling a power of a light beam;
- and
- a current outputting step of supplying a current to an emission section based on an emission pattern which is selected from between the data recording emission pattern and the test emission pattern, wherein,
- the test clock generation step includes a step of generating the test clock signal so as to have a constant frequency irrespectively of a linear velocity at recording.
4 more elements
Dependencies are inferred from the claim text.