Optical power level-controlling device for reduced reproduction jitter
AssigneeMitsumi Electric Co., Ltd.
InventorYuichi Maekawa
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AssigneeMitsumi Electric Co., Ltd.
InventorYuichi Maekawa
Estimating the term…
An optical power level-controlling device controls optical power level, such as a first reference level, a higher second level and a higher third level, of a laser beam irradiated on an optical disk. A table is created which contains second level indication data (difference between the second and first levels) for each of the second levels varied in a stepped manner and third level indication data (difference between the third and second levels) for each of ratios of the second level indication data to the third level indication data, the ratio being varied in a stepped manner. Optimum second level and optimum ratio for an optical disk are determined based on product information read from the optical disk. A second level and a ratio to be used for controlling an optical power level are retrieved from the table using the optimum second level and the optimum ratio.
An optical power level-controlling device for controlling optical power level of a laser beam emitted from a light-emitting element and irradiated on an optical disk, said optical power level capable of taking a first level defined as a reference level, a second level higher than said first level and a third level higher than said second level, a second level indication data being defined as a difference between said second level and said first level and a third level indication data being defined as a difference between said third level and said second level, said device comprising:
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