Method and apparatus for phase and/or copy window control use with a domain expansion recording medium and record carrier
AssigneeKoninklijke Philips Electronics N.V.
InventorCoen Adrianus Verschuren
Life of this patent
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Abstract
A method and apparatus for controlling read-out and/or synchronization between an external magnetic field and written data during a reading operation from a magneto-optical recording medium includes generating a pulse in a reading signal in a read-out layer by copying a mark region from a storage layer to the read-out layer upon heating by a radiation power and with the aid of the external magnetic field. The waveform of the reading signal is analyzed, and the analysis result is used for correcting a phase deviation and/or for controlling a copy window size of the mark copying. Phase errors may thus be corrected for any size of the copy window. Even small changes in the copy window can be detected and corrected.
Claims19
A method of controlling read-out from a magneto-optical recording medium, said recording medium comprising a storage layer and a read-out layer, wherein an expanded domain leading to a pulse in a reading signal is generated in said read-out layer by copying a mark region from said storage layer to said read-out layer upon heating by a radiation power and with the aid of an external magnetic field, said method comprising the acts of:
- providing said reading signal to a clock generator for generation of a clock signal supplied to an optical pick-up unit and a magnetic head driver;
- an analysis act including providing said reading signal to an analyzer for analyzing the waveform of said reading signal and forming an analysis signal, and
- a controlling act including providing said analysis signal to a controller for controlling a copy window size of said mark copying based on said analysis signal by applying a first control signal to said optical pick-up unit and a second control signal to said magnetic head driver.
A reading apparatus for controlling read-out from a magneto-optical recording medium, said recording medium comprising a storage layer and a read-out layer, wherein an expanded domain leading to a pulse in a reading signal is generated in said read-out layer by copying a mark region from said storage layer to said read-out layer upon heating by a radiation power and with the aid of an external magnetic field, said apparatus comprising:
- a clock generator configured to receive said reading signal and generate a clock signal which is supplied to an optical pick-up unit and a magnetic head driver;
- analyzing means for analyzing the waveform of said reading signal and forming an analysis signal;
- and
- control means for controlling a copy window size of said mark copying based on said analysis signal by applying a first control signal to said optical pick-up unit and a second control signal to said magnetic head driver.
Dependencies are inferred from the claim text.