A disc-shaped information recording medium in which the recording density can be increased to secure a large storage capacity and in which there is no risk of an address section being mistakenly detected by cross-talk from a neighboring track, is disclosed. Specifically, an optical disc of a continuous servo system in which tracking is controlled using a pre-groove and in which information is recorded and/or reproduced with constant angular velocity using clocks of a sole frequency, is disclosed. On the disc is formed a spiral a track made up of a data portion for recording data and an address section for recording management information for recording/reproducing data. Both a groove and a land are used as a recording/reproducing track. Odd tracks are formed on the land, while even tracks are formed on the groove.

A recording medium such as an optical disk with address information retained relative to tracks where data are recorded and/or reproduced. In this disk, lands and grooves are arranged alternately, and either the lands or the grooves constitute tracks. The grooves wobbled on the basis of address information and the non-wobbled DC grooves are arranged alternately while the lands are interposed therebetween. There is also provided an optical disk apparatus which comprises an irradiator for irradiating a first light beam spot to a target track on the optical disk, and further irradiating second and third light beam spots to the diametrical two sides of the center light beam spot; a light beam receiver for receiving the reflections of the first, second and third light beam spots from the optical disk, to thereby obtain first, second and third signals; and a calculator for calculating an address signal on the basis of the second and third signals.

A disc-shaped information recording medium in which the recording density can be increased to secure a large storage capacity and in which there is no risk of an address section being mistakenly detected by cross-talk from a neighboring track, is disclosed. Specifically, an optical disc of a continuous servo system in which tracking is controlled using a pre-groove and in which information is recorded and/or reproduced with constant angular velocity using clocks of a sole frequency, is disclosed. On the disc is formed a spiral track made up of a data portion for recording data and an address section for recording the management information for recording/reproducing the data. Both a groove and a land are used as a recording/reproducing track. Odd tracks are formed on the land, while even tracks are formed on the groove.

A disc-shaped information recording medium in which the recording density can be increased to secure a large storage capacity and in which there is no risk of an address section being mistakenly detected by cross-talk from a neighboring track, is disclosed. Specifically, an optical disc of a continuous servo system in which tracking is controlled using a pre-groove and in which information is recorded and/or reproduced with constant angular velocity using clocks of a sole frequency, is disclosed. On the disc is a formed spiral track made up of a data portion for recording data and an address section for recording management information for recording/reproducing data. Both a groove and a land are used as a recording/reproducing track. Odd tracks are formed on the land, while even tracks are formed on the groove.

The mark length of each of pits forming together the pit train is made shorter than that of each of pits for a to-be-written signal normalized at the predetermined bit interval T. Also, the mark length of a shortest one of the pits forming together the pit train is set to 64.8 to 80.0% of the shortest mark length for the to-be-written signal normalized at the predetermined bit interval T.