LASER TRANSMISSION THROUGH A DIELECTRIC-COATED HOLLOW TAPERED METALLIC WAVE-GUIDE

The transmission of a Gaussian beam through a dielectric-coated hollow tapered metallic waveguide is numerically evaluated. It is shown that thr tapered hollow coated circular waveguide has a loa: transmission loss with a large usable spectral window and that an unfocused laser b eam can be launched into the waveguide with low coupling loss. A diele ctric coated hollow tapered waveguide of optical quality is fabricated using a procedure involving core preparation, vacuum coating and acid etching. Efficient light transmission through a non-tapered (uniform bore) and tapered dielectric-coated hollow metallic waveguide is obser ved. (C) 1997 Elsevier Science B.V.