The thickness of a liquid crystal layer of a reflection type or semi-transparent type liquid crystal display device and the driving voltage are determined in such a manner that the reflectance of the liquid crystal layer to the blue light component has a maximum value; the values of reflectance to the red, green and blue light components are close to one another in the range lower than the driving voltage; the reflection type or semi-transparent type liquid crystal display device produces a full color image in the driving voltage range where the values of reflectance are close to one another so that the color irregularity and tint irregularity are suppressed.