Method of secondary modulation of a train of recorded data

Abstract

A secondary modulation method which replaces any bit excluding the leading bit of consecutive five or more ones in an odd-numbered bit pattern of a train of RLL-modulated data, with a zero to provide a modulated bit pattern having no consecutive zeros. It is therefore possible to form marks of a given width on a disk without any mark edge shift, thus preventing the level of the waveform of a signal read from a disk from falling below the slice level at the position where the waveform of the read signal should show "1". This can ensure the proper data reproduction.

Dependencies are inferred from the claim text.