High-resolution observations of the Orion KL regions in dust continuum emissions at λ=2 millimeter with the Nobeyama Millimeter Array (NMA) are presented.Visibility phases of the continuum emissions were calibrated by using the phase of the SiO maser emission which was simultaneously detected,allowing us to obtain high quality images with high angular resolution(~1.5").Cloud cores with (1-20)solar masses can be identified in our map,and the smallest one could be a formation site of a brown dwarf.The results of phase correction experiments on 28 March 2002 using differential radiometers operating at 191GHz on two NMA antennas are also presented.Difference in sky temperature measured by the radiometers and visibilities phase of quasars with NMA antennas shows tight correlations.The phase fluctuation in raw visibility data is reduced by ~60% after subtracting the time variation of the phase estimated from the output of the radiometers.