In an ECB LCD, in which a liquid crystal layer enclosed between a pair of substrates is driven based on R, G, B signals so that transmittance of R, G, B light components at the liquid crystal layer is controlled for color display, the voltage levels of the liquid crystal driving signals for R, G, B light are set such that the optimum transmittance, i.e., the maximum transmittance, can be achieved with respect to the R, G, B light components. With this arrangement, wavelength dependency, if any, of the liquid crystal with respect to the light coming into the light crystal layer can be modified so that color display is achieved with superior color reproducibility.