The solid volumetric true−3D display requires light source with high brightness, high energy utilization rate and high frequency color field. So high−power red, green and blue LEDs with collimators were used as the projection light source. Firstly, the required quantity of LEDs was determined according to the required output luminance, the efficiency of the projector and the red, green and blue LEDs' parameters. Secondly, with the consideration of the LEDs' dimensions, light−emitting mode and output luminous flux, collimator was designed and simulation model was established. Simulation and practical measurement results both show that light source based on high−power LED meet the requirements of the solid volumetric true−3D display.

A solid-state volumetric true 3D display developed by Hefei University of Technology consists of two main components: a high-speed video projector and a stack of liquid crystal shutters. The shutters are based on polymer stabilized cholesteric texture material, presenting different states that can be switched by different voltage. The high-speed video projector includes LED-based light source and tree-chip digital micro-mirror devices modulating RGB lights. A sequence of slices of three-dimensional images are projected into the liquid crystal shutters locating at the proper depth, forming a true 3D image depending on the human vision persistence. The prototype is developed. The measurement results show that the screen brightness can reach 149 nit and no flickers can be perceived.