| 摘要 |
PURPOSE:To enable the recording of a large amount of information in spite of using a modulation method capable of self-clocking by obtaining an information reproduce clock using a part of information in an adjacent area. CONSTITUTION:An information track 201 is separated from adjacent information tracks with a separation area 202. The information track 201 comprises a num ber area 204 showing its track number and a unit data area 205; each unit data, comprising 5 bits, is 4/5-converted, also NRZI-modulated and recorded, excluding signals other than those of T, 2T or 3T length. An area with an invert interval of 4T is used as the separation area 202. All MSBs of the code of the track number are '1' after 4/5-NRZI-modulated; the NRZI modulation is to invert a signal exclusively when MSB='1'; thus the LSB of the separation area 202 and the MSB (first bit) of the number area 204 can be used as a com mon bit and hence bits can be reduced. |
