Optical disc having specified track pitch, push-pull signal, and cross-track signal

摘要

The present invention provides a rewritable optical disc which is compatible with a DVD-ROM reproduction apparatus and employs the groove recording method. The optical disc has a recording layer having a land 10 and a groove 9 onto/from which an information signal is recorded and reproduced with a light of a predetermined wavelength, wherein if it is assumed that the groove has a bottom width W1 and an opening width W2, then a groove average width X [mum] can be expressed as follows:and if the groove has a depth Y nm, then X and Y satisfy the following relationships: