To preventing a deterioration in NMR signals due to a slice-leaned state, in executing a pulse sequence by the spin echo method, the inclination angle G2 of the slice gradient at the time of applying a 180 RF pulse P is made smaller than the inclination angle G1 of the slice gradient at the time of applying a 90 RF pulse R. Each turn of the first separator is disposed between each outer surface of the turns of the negative electrode and each inner surface of the turns of the positive electrode. Then, the method converts each grayscale value of the image to a Z height value, thereby generating a digital file of X, Y, and Z values.