Patent ID: 11956882
Assignee: RADOM CORPORATION
Field: Chemical engineering (Chemistry)
Classification: CPC H | IPC H

Claim 21:
22. A plasma torch comprising:
a radiofrequency energy source;
a dielectric ring providing a central opening extending along an axis;
a tuned cavity surrounding the dielectric ring having a resonant radio frequency matching a circumferential resonant frequency of the dielectric ring, the tuned cavity having opposed bases along the axis;
a first gas port for introducing plasma feeder gas along the axis through an entrance in a first base of the tuned cavity to pass through the central opening and out an exit in a second base of the tuned cavity; and
at least one electrically conductive choke sleeve covering at least one of an entrance and exit in the tuned cavity and extending at least one centimeter from the tuned cavity along the axis or at least 4 times the inverse of the attenuation constant of the waveguide below cutoff formed by the inner surface of the sleeve.