Research On Speckle Suppression In Laser Micro-Projector

Recently, with the development of laser projection displays, speckle phenomenon has received much attention. In this paper, speckle patterns size, contrast and the sums of speckle characteristic are studied theoretically. It layes a theoretical foundation for the methods of suppressing speckle.In this thesis, the characteristic of the detectors are studied, and point that speckle patterns detected by CCD is scale-invariant to the eyes, because of the speckle patterns' Fractal features. Then we analyze the speckle configurations' influencing factors, including the screens' configuration, angle of the light source or the detector, and the detector's time of exposure. We conform our attentions to the space characterstic of the speckle patterns, finding out the variation of speckle contrast with spatial value. The other significative work in this paper is to analyze the principle of suppressing speckle with a moving diffuser, basing on the eigen function theory of partially coherent optical systems. This method can easily provide a theoretical basic for the diffuser production program and the illumination mode.At last, advantages and disadvantages of the suppression techniques are expounded. And choose compounding the moving diffuser and speckle suppression techniques as the practical programs. Then the further work also prospected.