Extruded polycrystalline KRS-5 fiber exhibits a large amount of residual strain. This strain, which results from the large forces applied in the extrusion process, is a major contribution to the total attenuation. To study the effect of strain on fiber loss, we have measured the total attenuation coefficient ατ and the attenuation coefficient due to scattering, αs, as a function of stress applied along the fiber axis. The applied stress σ induces a change in the refractive index, which in turn leads to bulk scattering and excess fiber loss. We have found that ατ ~ σ2, which is in accord with an extension of a recent theory by Harrington and Sparks.
© 1983 Optical Society of America
James A. Harrington and Arlie G. Standlee, "Attenuation at 10.6 µm in loaded and unloaded polycrystalline KRS-5 fibers," Appl. Opt. 22, 3073-3078 (1983)