| 摘要 |
PURPOSE:To make a rising temp. on a medium constant even when the temp. of the medium is different and to write uniform data pulses by estimating a temp. of the medium and changing a laser power value at the time of erasing and writing to meet the temp. of the medium. CONSTITUTION:First of all, an initial setting valve of laser power for a write test is set to a laser power setting register 16. Then, write and read operations are performed in a test sector, and the set value of the register 16 is decreased by a fixed value at a time until non-coincidence of data exceeds a reference, so as to obtain lower limit laser power. Then, a temp. of the medium 1 at the time of its insertion is obtained from a table 17, and then the optimum laser power is obtained from a table 18, so that this value is set to a register 16. Afterward, at intervals of a given period of time, the present temp. of the medium is estimated in turn by using a specified formula. Under these circumstances, when a write request is issued from a host computer 01, the optimum laser power is obtained with the latest estimated temp. from the table 18, and is set to the register 16. By this method, the optimum data write is thus performed. |
