Look, no glasses

Three-dimensional display systems generally require the user to wear special glasses. The author describes a research programme-aimed at providing a high-quality spectacle-free look into the third dimension. It is based on the Twin-LCD display concept developed by the Imaging Technology Department at Sharp Laboratories of Europe. The author describes how the Twin-LCD system works. It is based on two thin-film transistor (TFT) LCDs whose images are superimposed by a half-mirrored beam-combiner. The input optical arrangement creates two laterally displaced images at the nominal observer position. If an observer places an eye in a window, then an image from one of the LCDs can be seen. Each LCD panel displays one of the stereo pair images and so the observer sees the 3D image without the need for any special glasses.