Record carrier, device for recording to the carrier and/or playing back from the carrier and process for producing such record carrier

摘要

In the present invention, there is disclosed a record carrier (1) comprising a servo track indicating an information track intended for recording information blocks represented by marks having lengths expressed in channel bits, which servo track (4) has a periodic variation of a physical parameter. The periodic variation is modulated for encoding record carrier information, such as addresses. The modulation is a bi-phase modulation in which a data bit of the record carrier information is encoded by a first predetermined number of variations of a first phase followed by the same number of variations of a second phase inverse to the first phase.