Holographic prototype enables mid air displays

According to Edinburgh based Holoxica, the idea is to expose a series of holograms on a single sheet that is rear illuminated by a laser projector. While similar multi-exposure holograms have been demonstrated before, showing different views of the scene as the viewer moves from side to side, Holoxia's views are all visible from a stationary viewing position. And, adds the company, the views can be turned on and off with electronic control, creating a series of 'flip card' images that appear to float in front of the A4 sized screen. The company has been working for three years, in collaboration with the University of Edinburgh and Heriot Watt University, to develop the technology from prototype into a commercialised product. "The 'mid air suspension' holographic screen currently embeds up to nine images, but this number can be scaled up," said Javid Khan, managing director of Holoxica. "Indeed, we can scale up toward 25 images, where it is possible to get a second of full 3D video or make other kinds of animated characters. Although colour is limited at the moment, the plan is to extend this in the future to give full colour images by combining red, green and blue light sources." Full electronic holography based on using laser illuminated spatial light modulators is highly compute intensive and limited on size, but Khan believes he has addressed this by taking an approach that is 'somewhere between volumetric and holographic techniques'. The process has been simplified by exposing multiple holograms in a diffractive sheet and using fairly simple laser illumination. "However, the trade off is that the holographic display is limited to simple volumetric shapes such as alphanumeric segments, icons or short animation sequences," noted Khan.

Holoxica holographic 3D display prototype from Holoxica on Vimeo.