1. A color adjustment apparatus which receives an input luminance signal and an input chromaticity signal comprising: chromaticity value setting means for setting a preselected reference chromaticity value; area setting means for setting an area on a chromaticity plane that includes said preselected reference chromaticity value; weighting coefficient setting means for setting a weighting coefficient that is zero outside said area as set by said area setting means and gradually increases to one as a distance between said preselected reference chromaticity value and said input chromaticity signal becomes small; and first calculation means for internally dividing said input chromaticity signal and said preselected reference chromaticity value based on said weighting coefficient and for producing a color-adjusted chromaticity signal.