
The light emitting surface of an image display light box is formed of multi-layer optical film having a reflectance greater than 95% and preferably about 99% or greater. This more efficiently utilizes light rays emitted by the light box's internal light source, since the multi-layer optical film reflects the light rays many times before the rays are absorbed and lost. Consequently, the light emitting surface can have a light transmissivity characteristic which is macroscopically invariant as a f...











