All-Round Accommodator: Realistic Three-dimensional Aerial Projection Using Pepper's Ghost and Focal Length Change

This paper proposes a three-dimensional aerial projection device, All-Round Accommodator, with rich reality using Peppers Ghost and variable focal length lens. In order to achieve improvement of rich reality of aerial projection, our proposed device incorporates two factors of motion parallax and accommodation. The former achieves all-round view by using the property that the pepper's ghost can be observed from many directions. We can perceive three-dimensional effect when projection is moving. The latter is achieved by combining a volumetric display and a variable-focal lens. An advantage of accommodation is to realize three-dimensional reality even when projection is not moving, i.e., still. In order to prove our system is feasible, a prototype zero for demonstration has been designed, implemented and experimented if we can feel three-dimensional effect from aerial projection. Experimental results have shown our principle performed properly.