A high density optical information recording medium comprises a substrate
having rows of land and groove and a recording layer formed on the
substrate. Each of the rows of land or groove includes at least two
recording tracks separated by a denatured region produced by irradiating
e.g. the center of each row in the recording layer with a denaturing
light beam accompanied with one or two sub-beams for tracking control.
Recording and reproduction of information can be performed likewise by
using a recording or reproduction light beam accompanied with one or two
tracking sub-beams.