Optical reproduction apparatus

摘要

An optical reproduction apparatus for reproducing information from an optical recording medium having grooves and lands alternately provided in a radial direction, information recording areas being formed in both of said grooves and said lands, and at least one prepit region where a groove is not formed. In the prepit region, first information marks are disposed on a virtual extension of a first boundary between one groove and one adjacent land and second information marks are disposed on a virtual extension of a second boundary between the one groove and an other adjacent land. A trailing edge of the first information marks is aligned in the radial direction. The optical reproduction apparatus includes an irradiation source for irradiating a light spot on the optical recording medium, a detector for detecting a reflected light from the optical recording medium, and a reproducer for reproducing information by using a signal from the detector.