1. A phase difference enhanced imaging method comprising: a first step of creating a phase difference image using a first complex image including a magnitude image and a phase image obtained from a magnetic resonance signal and a second complex image obtained by filtering the first complex image; a second step of creating an enhanced image through selecting a phase corresponding to an objective tissue in the phase difference image taking account of change in distribution of phase difference due to the filtering, and selecting an exponential function as an enhancement function for enhancing the selected phase, and enhancing the selected phase by the exponential function; and a third step of creating a phase difference enhanced image by masking a predetermined image with the enhanced image.