| 摘要 |
A discrete-track-recording (DTR) disk (also called "patterned" disk) has a sectored servo formed by modulation of its sidewalls in a predetermined manner, whereas sidewalls of data sectors are not modulated in this manner. Each servo sector has two side walls that are each respectively modulated in two different ways. Hence, a readback signal from a given servo sector contains components of each of the two different modulations, even in case of "DC" erase initiation. Therefore, the just-described modulated servo sectors eliminate servowriting. Moreover, data signals are read without filtering the modulation, because data sector sidewalls are not modulated.
|
