Speckle decrease system for coherent illuminant, decrease method of speckle contrast, and speckle decrease system of illuminating

摘要

(57) Abstract The speckle decrease system divides pulse of coherent light into parusuretsuto of one group. parusuretsuto is segregated timewise, the wave front surpasses the strain spatially. bimusupuritsuta 30 of 1 or more, divides the above-mentioned pulse into the group of parusuretsuto. These parusuretsuto circulate, paralleling to delay line 22,24,26,28. Spatial wave front strain formation vessel 50,52,54,56,58 is provided on the middle of the delay line. Wave front strain formation vessel 50,52,54,56,58 changes the wave front form of parusuretsuto. As parusuretsuto is segregated timewise, speckle pattern of one group which differs mutually by making be warped spatially, is formed. Speckle pattern of these one groups is averaged mutually during addition period of the instrument. With this, speckle contrast is decreased.