Patent attributes
An optical recording apparatus having a light source and an optical system. The medium is a substrate in the form of a substantially circular disk with grooves and lands alternately formed on the substrate in a radial direction. The grooves and lands both serve as recording tracks which are divided into recording units in a circumferential direction. Each recording unit has an address area devoid of the grooves including first and second address information. The first address information is formed on a first boundary between one track and an adjacent track on one side of the one track, and the second address information is formed on a second boundary between the one track and an adjacent track on an other side of the one track with the first address information and the second address information not existing at opposing positions on the boundaries of the one track.