Individual adjustment of pit and land transition locations in an optical disc mastering process

Abstract

An apparatus and method are disclosed for optimizing the writing of data to an optical disc to improve readback characteristics and minimize the effects of errors. An optimization circuit generates an optimized modulation signal which is used to modulate a writing beam of a laser beam recorder, the optimized modulation signal comprising a series of data symbols that correspond to resulting pits and lands on the optical disc. The optimization circuit optimizes the locations of pit and land transitions on the optical disc by individually adjusting leading and trailing edges of the data symbols, as well as amplitudes of the data symbols. In this manner, the particular length of each pit and land on the disc can be individually selected based on nominal symbol length, as well as other factors including radial and angular locations of the pits and lands on the disc. Moreover, the selective placement of pit and land transitions can be used to embed a second set of data on the optical disc to provide watermarks or anti-piracy hidden codes. Finally, electrical jitter errors, including data correlated jitter, can further be minimized through a master driver circuit which can be used to reclock an initial modulation signal prior to generation of the optimized modulation signal by the optimization circuit.