The present invention relates to a method for optical recording in which
information is recorded on an optical recording media utilizing
holography and to a method for optical reproducing in which information
recorded on an optical recording media utilizing holography is
reconstructed. The methods includes preparing an optical recording media
having wavelength reference marks with a periodic structure which are
associated with a recording base wavelength, irradiating the wavelength
reference marks with a beam from a light source on recording information
or on reproducing information to detect a wavelength shift of the light
source with respect to the base wavelength based on a diffraction beam
from the wavelength reference marks, and performing recording or
reproducing while controlling the wavelength of the light source so as to
reduce the wavelength shift.