SELF-SERVOWRITING TIMING PATTERN GENERATION

摘要

Improvements in placement of timing patterns in self servo writing include c orrecting for random and systematic errors due to geometric effects. In a disk drive h aving a recording head with separate read and write elements, a method for determini ng separation between the elements and for correcting for such errors as a func tion of skew angle between the head and the disk. Errors resulting from misalignment andnon-parallelism of the elements as well as misalignm ent of the head on it its actuator are also detected and corrected. Errors due to changes in rotational velocit y of the disk and misplacement of timing patterns with respect to adjacent timing patterns aredetected and corrected. In general, a single revolut ion process may be used to both write and detect random errors on each track and corrected on subsequent tra cks.