Transparent poster with direct and indirect lighting - has semi-reflective element between light source and transparent poster

摘要

The arrangement is intended for illuminating a transparent poster or sign board (1) from behind and comprises a light source (3) and an optional reflector (2). An auxiliary optical element (4), arranged between the light source and the transparent poster etc. is semi-reflective. Thus it throws part of the light back and passes as much as possible of the remainder. The arrangement is such that the light density distribution over the entire surface of the transparent poster has maximum uniformity. The optical element may be arranged directly on a fluorescent lamp or on the rear surface of the transparent poster.