Photography. any device for exposing an image on film, a sensitized plate, etc., by tracing light along a series of many closely spaced parallel lines.
(in aerial photography) a device for estimating the ratio of aircraft speed to aircraft altitude.
a photoelectric device for scanning a picture to determine automatically the density of the hue or value in each area for transmission by wire or radio or for preparation of color process printing plates.
a computer-aided electronic system using photoelectric cells to separate copy, as color illustrations, into its primary colors, correct color copy, and produce a set of color separations ready for proofing or printing.
Radio. a radio receiver, used especially by police, firefighters, and the press, that continuously tunes to preselected frequencies, broadcasting any signal that it detects.
Medicine/Medical, Biology. a device for examining a body, organ, tissue, or other biologically active material.