Abstract: A one-way see-through illumination system is constructed from a light guide panel, a front-illuminable image film, and a light injector. The light injector injects light into the light guide panel at a suitable angle for total internal reflection of the injected light at the surfaces of the light guide panel. The image film includes a half-toned front-illuminable image pattern that extracts light from the light guide panel. When active, light from the light guide panel front illuminates the image pattern for viewing by a front-side view, while a back-side viewer can see through the image pattern.

Abstract: An illuminable marking device includes a light guide panel overlaid with an illuminable pressure-sensitive film. Light is injected into the light guide panel at an angle of incidence sufficient to establish total internal reflection of the light between the surfaces of the light guide panel. When pressure is applied at selected points on the illuminable pressure-sensitive film, contact points on the film then interface with the light guide panel. The total internal reflection of light at that contact point is frustrated, allowing light to be extracted from the light guide panel and transmitted into the illuminable pressure-sensitive film. The viewer then sees illumination at the selected points. The illuminable marking device can be toy where children can create illuminated markings and drawings.