The sense of equilibrium is influenced by various factors of visual stimulation, especially far peripheral vision and a motion parallax. An investigation of these two factors was made in order to apply the findings to construct a rehabilitation method for equilibrium disorders. From the experimental results, it was found that the center of gravity for the subjects was greatly affected by both far peripheral vision and the motion parallax. This finding suggests how visual stimulation should be displayed to control the sense of balance in the case of equilibrium disorders.

In this paper, we first discuss on a framework for a 3D image display system which is the combination of passive sensing and active display technologies. The passive sensing enables to capture real scenes under natural condition. The active display enables to present arbitrary views with proper motion parallax following the observer's motion. The requirements of passive sensing technology for 3D image displays are discussed in comparison with those for robot vision. Then, a new stereo algorithm, called SEA (Stereo by Eye Array), which satisfies the requirements is described in detail. The SEA uses nine images captured by a 33 camera array. It has the following features for depth estimation: 1) Pixel-based correspondence search enables to obtain a dense and high-spatial-resolution depth map. 2) Correspondence ambiguity for linear edges with the orientation parallel to a particular baseline is eliminated by using multiple baselines with different orientations. 3) Occlusion can be easily detected and an occlusion-free depth map with sharp object boundaries is generated. The feasibility of the SEA is demonstrated by experiments by using real image data.