Optical storage medium, a tilt detection apparatus, and a data recording and reproducing apparatus

摘要

Tilt of an optical storage medium is stably detected even when then the guide groove pitch is reduced and recording capacity is increased. On a disk with continuous grooves of a pitch Gp, part of tracks Gn-1 and Gn+1 adjacent to opposite sides of an n-th track Gn is eliminated, forming an area where the groove pitch is equivalent to 2.Gp. A push-pull signal from the area of groove pitch Gp and a push-pull signal from the area of groove pitch 2.Gp are differentiated to obtain a tilt error signal. Tilt can therefore be detected even when groove pitch Gp is reduced and storage capacity is increased, and a highly reliable data recording and reproducing apparatus can be provided at low cost.