DRIVER FOR SPECKLE REDUCTION DIFFUSING SCREENS
Original Publication Date: 1980-Feb-29
Included in the Prior Art Database: 2004-Apr-02
Xerox Disclosure Journal
To reduce the small scale scintillation or "speckle" of an optically projected image, the projection system includes a pair of closely spaced, counterrotating diffusion screens 11 and 12 for producing controlled diffusion of the projected image. The counterrotation of the screens 11 and 12 not only reduces by a factor of two the angular velocity at which the screens 11 and 12 must be driven to achieve a given amount of diffusion but also tends to cause counterbalancing of any mechanical imbalance the individual rotating screens 11 and 12 may exhibit.