The liquid crystal display device inputs a signal, corrected by a
correction circuit provided with a sigmoid inverse function generator, to
a source driver. A sigmoid function which is an S-shaped function is used
to approximate an input/output characteristic (applied
voltage-transmittance curve) of a liquid crystal panel. The sigmoid
inverse function generator converts an input signal by using an inverse
function of the sigmoid function obtained by performing the
approximation. A .gamma. conversion circuit provided on the correction
circuit and the sigmoid inverse function generator realize the desired
.gamma. characteristic regardless of a characteristic of the liquid
crystal panel. Further, since the inverse function of the sigmoid
function which is an S-shaped function is used, it is possible to provide
a display device which corrects the input/output characteristic of the
display panel by performing the approximation in accordance with not
plural functions but a single function (without dividing the
characteristic into sections).