Patent ID: 6259208
Filing Date: 2001-07-10
Classification: H01J

Abstract:
A magnetron having a microwave frequency range of operation, comprising:an anode block;a resonant cavity defined within the anode block;apparatus for optically tuning a magnetron operating frequency within said range of operation, comprising a probe structure extending into said resonant cavity, said probe structure comprising a leaky dielectric light guide structure to which a photoconductive coating structure has been applied, a light source for directing light into the probe structure, apparatus for modulating the intensity of the light directed into the probe, wherein light propagating through the dielectric light guide structure leaks into the photoconductive coating structure, and is absorbed by the coating structure through creation of electron-hole pairs, causing the coating structure to reflect incident microwave radiation, the degree of reflection dependent on the incident light intensity, wherein the resonant frequency of the resonant cavity and the frequency of operation of the magnetron is tunable by modulating the intensity of the light directed into the probe structure and thereby changing in reflectivity of the coating structure, wherein said leaky dielectric light structure comprises a plurality of optical fibers, each fiber comprising a dielectric fiber with no cladding formed on the exterior surface of the dielectric fiber along a probe length portion, and said photoconductive coating structure comprises a photoconductive coating applied to the outer surface of each said dielectric fiber along said probe length portion.