In the case of a four-eye type stereoscopic viewing system, four videos (dots) "video {circle around (1)}, video {circle around (2)}, video {circle around (3)}, and video {circle around (4)}" composing each of minimum units of video group are repeatedly arranged in a horizontal direction of a screen, and the minimum units of video group are arranged so as to be shifted by one dot in the horizontal direction per row. Edges for defining the width of an aperture are obliquely formed in correspondence with the shift in the horizontal direction of the minimum units of video group, and the aperture is formed so as to extend across the respective minimum units of video group on the rows, the edges being straight.