The optical information recording and reproducing apparatus, a recording condition adjusting method and an optical information recording medium

In the optical information recording and reproducing apparatus utilizing holography, variations and during recording of the environment, variations in the components of the laser output, etc., due to manufacturing variations or the like of the device, to be adjusted conditions at the time of recording, the signal-to-noise at the time of reproduction since the ratio (SNR) to address the problem of decreased provides an optical information recording and reproducing apparatus to properly adjust the recording condition and the method and medium. In using holography optical information recording and reproducing apparatus for recording or reproducing information on an optical information recording medium, the adjustment of the recording conditions before user data recorded in the adjustment region provided for the recording condition adjustment in the optical information recording medium do.