In order to satisfy users with different requirements, 3D display technology still keep developing and extending, but the important issues about viewing fatigue and discomfort still can't be solved. This paper will introduce the cause of fatigue induced by viewing 3D images and the relationship between fatigue and physiological structures. In addition, the index of physiological measurement about fatigue will be explained, too. In this paper, we'll in display manufactory's respect to talk about how to improve the 3D display.