| 摘要 |
PROBLEM TO BE SOLVED: To perform recording and reproducing by using plural adjacent channels on a disk. SOLUTION: For example, a DRAW type optical disk is provided with guide grooves beforehand to be detectable by a laser beam. And, when a two-channel recording and reproducing is performed, for example, two guide grooves are provided in a double spiral form so that a prescribed spacing is allowed between them. Also, one of the guide grooves is made to be a continuous DC groove, while the other is intermitted in a specified pattern and arbitrary address information is formed to form an address groove. Further, between these guide grooves, two recording tracks a and b are formed in a double spiral form. Thus, a DC groove and an address groove are alternately formed on an optical disk 1, while the two recording tracks a and b are formed between DC grooves, and further, an address groove is formed between the recording tracks a and b. |
