Symbol carrier illuminating unit for photocomposing machine - uses light source and light rod between source and condenser

摘要

The light rod for the critical uniform illumination of a printing symbol on the symbol carrier is so arranged that it collects a large region of the source light distribution with its input end. The rod is of such a length that it radiates uniformly from its outlet following integration of the light flux. This uniformly illuminated surface is reproduced on the e.g. printing film. A condenser lens set positioned between the inlet of the light rod and the light source directs the light from the source to th rod inlet. The condenser lens set preferably enlarges the image projected onto the film. an additional condenser lens located between the condenser lens system and the symbol carrier ensures that edge radiation is parallel to the main axis.