Which Material Parameters Are Required For Hollow Fibers Transmitting High-Power IR.- Radiation?

Hollow fibers are regarded as potential waveguides for radiation from C0 2 -Lasers. We report on conditions for hollow fibers capable of delivering high-power radiation 100 W). We consider fibers with an air-filled core and a massive uncoated cladding. Technical requirements concerning the transmittance, numerical aperture, bending radius, and thermal effects lead to conditions for the refractive and absorption indices of the cladding material. Until now no oxide glass is known that is suitable for hollow fibers transmitting high-power radiation in the mid-infrared region. Further investigations were done with the parameters of crystalline, metallic and semiconducting materials. However, these materials do not fulfil the requirements of high-power hollow fibers either.