By introducing a refractor on the TV camera lens, the image of the measuring point is displaced on the image plane with the corresponding displacements related to the distances between the TV camera and the measuring point. The magnitude of displacement on the image plane is inversely proportional to the distance between the TV camera and measuring point. When the refractor is rotated physically at high speed during the exposure of the TV camera, annular streaks of measuring points appear on an image since the rotational shift is added to the image. Since the size of the annular streak is inversely proportional to the distance of the measuring point from the camera, the three-dimensional information can be calculated by analyzing annular streaks. In this paper, the surface measurement such as swinging water is introduced for one of the applications of our system.
