To provide a driving principle of a color display by taking the difference of sensitivities of human eyes against flickers of each color, a TFT liquid crystal display module structure suitable for this method, and a two-board system projection type display device.

Concerning a critical fusion frequency in which a flicker comes not to be felt and to be seen fused, G(green) is the highest, and also the sensitivity of human eyes is the highest, therefore, the number of writing of a G(green) color is made more than those of other primary colors or the display period thereof is taken longer, and instead of a repeating unit, R, G, B, by which a color image is usually driven sequentially a repeating unit, R, G, B, G, is newly set, to thereby set a refresh rate relative to important G as a necessary and sufficient one. Therefore, without degrading a display quality, a refresh frequency as a whole is reduced and the power consumption of a display element is reduced, and a requirement concerning a time response speed is mitigated.