Method of Temporal Average with Moving Diffuser for Suppressing Speckle

The theory of temporal average with a moving diffuser for suppressing speckle is realized by the experiment used a rigid PVC sheet and a treated K9 glass controlled by an external motor. By controlling the mechanical vibration of moving diffuser, a good speckle contrast can be achieved without loss of detailed information. The images about the speckle suppression and detailed information can be directly collected by a CCD and processed the digital images by MATLAB. By calculating the velocity of the moving diffusers, speckle contrast can be obtained. The results show that the speckle contrast after the dispose of the rigid PVC sheet and the treated K9 glass can be respectively reduced from 44.09% and 72.44% to 16.88% and 27.20% separately and the method is feasible and effective.

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