Inverse-square wavelength dependence of attenuation in infrared polycrystalline fibers.
The total-attenuation coefficient alpha(T) in polycrystalline thallium bromoiodide fibers varies as lambda(-2), in sharp contrast to the Rayleigh lambda(-4) dependence in silica fibers. We developed a model showing that this lambda(-2) ttenuation results from the combination of bulk scattering from large-scale, optically thin imperfections and surface scattering and absorption. The model also explains our scattering sphere result that the attenuation coefficient that is due to scattering, alpha(s), at 10.6 microm increases linearly with fiber length, in contrast to the situation in glass fibers in which alpha(s) is constant along the fiber.
Harrington
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JA
Sparks
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