In order to make a multi-media display system on which character images displayed with optimum display conditions for good readability or for less-fatigue and natural images displayed with good picture quality, the following experiments were carried out. The character contrasts were measured for the images of bright characters with dark background and for mixed images of natural picture and character images on the bases of[readability]or[fatigues]. On the criterion of[readability]for character images, the optimum character contrast was 83, and the range of acceptable limit of character contrast was from 45 to 100(max). And on that of[fatigue], the former is 53, and the range of acceptable limit of character contrast was from 30 to 80. The character contrasts measured for the mixed images on the criterion of[readability]and[fatigue]were almost equal to those obtained for character images.