RayGraphy: Aerial Volumetric Graphics Rendered Using Lasers in Fog

We present RayGraphy display technology that renders volumetric graphics by superimposing the trajectories of lights in indoor space filled with fog. Since the traditional FogScreen approach requires the shaping of a thin layer of fog, it can only show two-dimensional images in a narrow range that is close to the fog-emitting nozzle. Although a method that renders volumetric graphics with plasma generated using high-power laser was also proposed, its operation in a public space is considered quite dangerous. The proposed system mainly comprises dozens of laser projectors circularly arranged in a fog-filled space, and renders volumetric graphics in a fog by superimposing weak laser beams from the projectors. Compared to the conventional methods, this system employing weak laser beams and the non-shaped innocuous fog is more scalable and safer. We aim to construct a new spatial augmented reality platform where computer-generated images can be drawn directly in the real world. We implement a prototype that consists of 32 laser projectors and a fog machine. Moreover, we evaluate and discuss the system performance and characteristics in experiments.