DATA RECORDING METHOD AND DEVICE, DATA REPRODUCING METHOD AND DEVICE, AND RECORDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To record second data relating to first data other than the first data holding reproduction interchangeability. SOLUTION: Twenty-bit audio data is separated into first data of high-order 16 bits and second data of low-order 4 bits. EMF modulation data (Fig.2A) is created from the first data. A laser beam is turned on/off according to the logic level of channel data (Fig.2B) obtained by NRZI-modulating a serial data string. Consequently, the first data is recorded in the same way as in a compact disk. Each pit is controlled to have displacement in the horizontal direction with respect to the track center in accordance with the second data and a displaced pit is formed (Fig.2D). When data is recorded by the pit displacement, since a high frequency component of a tracking error signal changes during reproduction, the second data can be extracted from the tracking error signal. COPYRIGHT: (C)2009,JPO&INPIT