Portable emitter
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A portable emitter was a type of technology developed in the 24th century.
They were briefcase shaped devices that were capable of sustaining a hologram within two meters of it allowing them to work in areas without any form of holographic emitter so long as the portable emitter remained near them. This holographic generator also allowed for the creation of multiple holograms in an area as well as the capability of inputting new information within it which allowed for the alteration of the projection's appearance. (VOY novel: The Farther Shore)
