To display (~ a movie) and to hide (~ his view).

A tool with an extra semiconductor control layer which permits storing of images for controllable periods of at least an hour: The desired image is projected onto the electroluminescent display screen with ultraviolet light, and it is completely erased with infrared radiation.

1. An instrument which signals the exit of a missile from a predetermined trajectory or the path of a flying object.
2. An electronic device that indicates the departure of a missile from a predetermined trajectory or the path followed by an object moving through space.

The term sky screen refers to equipment that provides a posiive indication to the military range-safety officer whenever a missile deviates from its planned trajectory or its movement through space.

One sky screen monitors the flight bearing and the other sky screen monitors vertical programming.

An x-ray-intensifying screen made of rare-earth elements; such as, yttrium and gadolinium.

These screens make it possible for lower radiation doses to be used while producing acceptable film densities.