Optical reproducing method for optical medium with aligned prepit portion

摘要

An optical reproducing method using an optical recording medium having an aligned prepit portion straddled on a plurality of tracks in a radial direction which includes a first and a second prepit portion divided in a track direction. The respective first and second prepit portion are arranged on a boundary of respective tracks and include a synchronous information prepit arranged at every two-track pitch in the radial direction and positioned at opposite boundaries of the same track. A trailing end of the first prepit portion is aligned with the radial direction in arrangement. the method includes irradiating an optical spot on the optical recording medium, detecting a reflected beam from the optical recording medium, and reproducing information on the optical recording medium by using a signal obtained in accordance with the reflected beam.