Apparatus for recording and reproducing information on and from an optical disk

摘要

An apparatus for recording and reproducing information on and from an optical disk is disclosed in which at least one optical beam and a reference clock signal are used. The optical disk comprises recording tracks which are divided into a plurality of blocks and concentrically arranged along the radial direction. The apparatus comprises: a block judging unit for judging one of the blocks that the one block is currently impinged by the optical beam; a clock signal generator for generating a plurality of clock signals which are different in frequency from each other; and a clock signal selecting unit for selecting one of the clock signals as the reference clock signal, on the basis of the judgement of the block judging unit.