useful beam


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beam

 [bēm]
a unidirectional, or approximately unidirectional, emission of electromagnetic radiation or particles.
useful beam in radiology, that part of the primary radiation that is permitted to emerge from the tubehead assembly of an x-ray machine, as limited by the aperture or port and accessory collimating devices.
beam splitter a device that reflects light from the output phosphor of an image intensifier to a photographic recording. Called also image distributor.

useful beam

(in radiology) that part of the primary radiation that is permitted to emerge from the tube head assembly of an x-ray machine, as limited by the aperture or port and accessory collimating devices.