A High Efficiency Launcher and Mirror System for Use in a 110 GHZ TE22,6 Mode Gyrotron
Authors: Perkins, Michael; Cao, Rong; Neilson, Jeffrey; Vernon, Ronald
Source: International Journal of Infrared and Millimeter Waves, Volume 28, Number 3, March 2007 , pp. 207-218(12)
Abstract:A four-mirror internal quasi-optical mode converter designed for a CPI gyrotron is discussed. Many improved methods were used in designing the mode converter. The launcher was designed and analyzed using the TOL and Surf3d codes developed by CCR. Mirrors 1 and 2 were designed using analytic surfaces to shape the general wavefront curvature of the beam radiated from the launcher. Mirrors 3 and 4 were iteratively designed using improved techniques that produced smooth mirror surfaces. Good agreement was found between theory and low-power cold-test measurements. The fraction of power coupled between the target Gaussian beam and the output of mirror 4, inferred from measurements, was 0.990. The stray radiation from the internal quasi-optical mode converter, inferred from measurements, was only 1.9% of the total power radiated from the launcher. This resulted in a high overall system efficiency of 97.0%, which is greater than previous designs.
Document Type: Research article
Publication date: 2007-03-01