Recording method and recording apparatus
AssigneeHitachi, Ltd.
InventorsMariko Umeda, Hiroyuki Minemura
Life of this patent
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Abstract
A recording method and apparatus reduces jitter and increases the number of possible rewrites in an optical disc. When the absolute values of DSV values calculated for different DCC bits are equal, the selection of the DCC bit is carried out in a random manner, so that a different signal is recorded in each case on an optical disc medium even when the same user data is recorded. As a result, the deterioration of the marks and spaces is made uniform and the number of possible rewrites is increased.
Claims13
An information recording method for recording information on Blu-ray disc using an RLL (1,7) encoding rule, wherein a data string in which a DSV control bit for controlling DSV is periodically inserted is generated in recording data, said method comprising:
- generating a first and a second data string by modulating said data string for the case where said DSV control bit is “0” and the case where said DSV control bit is “1”, respectively, using in each case said RLL (1,7) encoding rule;
- selecting said first or said second data string in a substantially random manner;
- and
- recording one of the data strings thus selected on said Blu-ray disc when the absolute value of DSV of the one data string thus selected is smaller than a predetermined DSV absolute value.
A recording apparatus comprising:
- a light source for irradiating Blu-ray disc medium with a light beam;
- and
- an encoder for controlling a condition of said optical beam, wherein said encoder comprises:
- means for generating, in accordance with an RLL (1,7) encoding rule, a first data string for the case where a DSV control bit that is periodically inserted in a recording data string for a DSV control is “0”;
- means for generating a second data string for the case where the DSV control bit is “1”;
- means for calculating a first DSV value for said first data string;
- means for calculating a second DSV value for said second data string;
- and
- selection means for selecting either said first or said second data string based on at least either said first or said second DSV value.
Dependencies are inferred from the claim text.