Underwater integral photography

A novel integral photography (IP) system in which the amount of popping out is more than three times larger than usual is demonstrated in this study. If autostereoscopic display is introduced into virtual reality, IP is an ideal candidate because not only the horizontal but also the vertical parallax can be obtained. However, the amount of popping out obtained by IP is generally far less than that obtained by head-mounted display because the ray density decreases when the viewer is distant from the fly's eye lens. Although a solution is to extend the focal length of the fly's eye lens, this lens is difficult to manufacture. We address this problem by simply immersing the fly's eye lens into water to extend the effective focal length.