Hardy C Butler

US Patent:

6753516, Jun 22, 2004

Filed:

Dec 7, 2000

Appl. No.:

09/730804

Inventors:

Hardy Butler - Durham NC
Ben Adu - Frederick MD
J. Michael Drozd - Raleigh NC
William T. Joines - Durham NC
Esther Drozd - Lexington NC

Assignee:

Industrial Microwave Systems, L.L.C. - Morrisville NC

International Classification:

H05B 670

US Classification:

219745, 219693, 219695

Abstract:

A device for heating a material utilizes a rectangular waveguide with an elongated opening for passing a planar material through the rectangular waveguide. A source creates an electric field between a top surface and a bottom surface of the rectangular waveguide. The electric field is controlled to compensate for attenuation of the electric field. The electric field can be controlled by, for example, using a dielectric slab along the top surface of the rectangular waveguide or a tapered dielectric slab along the top surface of the rectangular waveguide. The electric field can also be controlled by, for example, making the waveguide appear electrically wider at one end. The waveguide can be made to appear electrically wider at one end by, for example, inserting one or more tapered fins. The tapered fins can be adjusted or removed to account for the lossiness of the planar material.