Title :
A quasi-optical mode converter with a bifocal mirror
Author :
Iatrou, Christos T.
Author_Institution :
Thomson Tubes Electron., Velizy-Villacoublay, France
fDate :
3/1/1995 12:00:00 AM
Abstract :
This paper presents the design procedure of a quasi-optical mode converter to transform any kind of TEmn mode into a Gaussian wave beam and experimental results obtained in the particular case of the TE64 mode at 110 GHz. The quasi-optical system consists of a helical-cut launcher and a bifocal mirror, which is designed, using the techniques of geometric optics, to focus the radiation of the launcher into a Gaussian focal spot. Such a system was fabricated and tested for the transformation of the TE64 mode. The experimental results showed that about 80% of the power incident in the focal plane is focused into a small Gaussian-like spot of less than 20 mm diameter, while 97% of the power is contained into the main TE64 lobe
Keywords :
geometrical optics; helical waveguides; millimetre wave couplers; waveguide couplers; 110 GHz; Gaussian focal spot; Gaussian wave beam; TEmn mode; Vlasov-type coupler; bifocal mirror; geometric optics; helical-cut launcher; quasi-optical mode converter; Electron tubes; Geometrical optics; Gyrotrons; Heating; Mirrors; Optical design; Optical waveguides; Tellurium; Waveguide components; Whispering gallery modes;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on