Patent ID: 7659520

Claim:
A detector for identifying substances at stand-off distances, by bombardment with radiant energy and subsequent analysis of energy returned responsively to bombardment by the substances being identified, comprising an emitter of radiant energy, comprising an orbitron disposed to emit radiant energy in the terahertz and microwave wavelength ranges, comprising a central conductor and a microwave cavity surrounding the central conductor, and an excitation system disposed to impose voltages on the central conductor, and to generate electric fields acting on the central conductor, thereby causing electrons to orbit around the central conductor and to be emitted at very high frequencies therefrom, and a reversing arrangement disposed to selectively reverse polarity imposed on the central conductor, thereby selectively emitting fast neutrons from the emitter of radiant energy; and an antenna disposed to receive radiant energy which is emitted from a substance responsively to being bombarded with radiant energy.