Projection of multiple directional images on a volume structure with refractive surfaces.

We present a new refraction-based approach to embed multiple images into a single volume structure rendered on a glass solid (3D crystal). Each of the images can only be revealed when looked at from the certain viewpoint. While configurations of viewing directions in conventional methods are limited, our method can compensate for refractive effects at glass surfaces regardless of the viewing directions and enable the viewing directions to be set more flexibly, even allowing for 180