Optical disc apparatus and method for writing data using laser beam
AssigneeHitachi-LG Data Storage, Inc.
InventorsMayumi Sasaki, Gohshi Jin
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Abstract
When an optical disc apparatus of the present invention writes to an optical disc, it detects the level of the drive voltage for its laser drive circuit and, based on the detected level, adjusts the drive voltage for its laser diode so as to adjust the drive voltage for the laser drive circuit to a level within an appropriate range. Further, the write speed is also adjusted in accordance with the above adjustment of the drive voltages for the laser drive circuit and the laser diode.
Claims4
An optical disc apparatus for writing data to and/or reading data from an optical disc by irradiating said optical disc with a laser beam, said optical disc apparatus comprising:
- a spindle motor for rotating said optical disc;
- a laser diode for generating and emitting a laser beam for reading and writing operations;
- a laser drive circuit driven by a first voltage generated from an applied power supply voltage, said laser drive circuit generating a second voltage for driving said laser diode;
- and
- a control circuit for, when data is written to said optical disc, detecting the level of said first voltage, comparing said detected level of said first voltage with a reference value and determining whether or not said detected level of said first voltage exceeds said reference value, and, based on said detected level of said first voltage, controlling said second voltage to adjust said first voltage to a level within a predetermined range, wherein:
- when said first voltage does not exceed said reference value, said control circuit reduces said second voltage to a level such that said first voltage exceeds said reference value, and
- said laser drive circuit is driven by said adjusted first voltage, and said laser diode is driven by the controlled second voltage.
A method for writing data using an optical disc apparatus that writes data to and/or reads data from an optical disc by driving a laser diode by use of a laser drive circuit and irradiating said optical disc with a laser beam emitted from said laser diode, said method comprising:
- a first step of detecting the level of a first voltage generated from an applied power supply voltage for driving said laser drive circuit;
- a second step of comparing said detected level of said first voltage with a reference value and determining whether or not said detected level of said first voltage exceeds said reference value;
- and
- a third step of, based on the result of said determination in said second step, controlling a second voltage generated by said laser drive circuit for driving said laser diode to adjust said first voltage to a level within a predetermined range,
- wherein when, in said second step, that said detected level of said first voltage does not exceed said reference value is determined, in said third step, said second voltage is reduced to a level such that said first voltage exceeds said reference value.
Dependencies are inferred from the claim text.