| 摘要 |
A translucent screen 1, the rear side 2 of which is illuminated by a lamp 4 or a projection device (not shown), has, on its front side, transparent or translucent regions 5 arranged alternately with lightproof and non-reflecting regions 6. The rear side 2 is formed with concentric lens-function surfaces 7 which focus beams from the lamp 4 towards the transparent or translucent regions 5 in such a manner that the majority of the light from the lamp 4 on the rear side 2 is transmitted through the screen 1. Any "wild" light beams, which strike the front side 3 of the screen, are either blocked by the lightproof regions 6, possibly after internal reflection against the lens-function surfaces 7, or "lost" in the region between the screen 1 and the lamp 4. In this way, reflections which can interfere with observation of the screen are avoided or considerably reduced. <IMAGE>
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