The Speckle Reduction Effect of Small Moving Diffusers in Laser Projection Displays

Abstract

On projection displays using laser light sources, speckles are generated by the high coherency of laser light. We have investigated the effect of a small moving diffuser placed at the conjugate point of a micro-display to reduce speckle, and have studied how the optical magnification ratio, the F-number of the projection lens and the diffusing angle range of diffuser affect the speckle reduction ratio.