Adjustment method of display device

An adjustment method of a display device having a light source and an optical modulator modulating light from said light source on the basis of an applied voltage, said adjustment method comprising:

• a first step of changing and setting said applied voltage according to different gradation values and measuring an optical power at each of the gradation values that is modulated by said optical modulator at a position corresponding to at least a first pixel;
• a second step of setting an applied voltage, corresponding to a constant gradation value, every measurement in said first step and measuring a reference optical power modulated by said optical modulator at a reference position corresponding to a second pixel, the reference position being different from the position corresponding to at least a first pixel;
• and
• a third step of correcting the optical power at each of the gradation values, which is measured in said first step, on the basis of said reference optical power measured in said second step.