HARD-COATED FIBER

A data sheet from Fiberguide Industries Inc. describes the company’s Anhydroguide AFSH silica-core and -clad fiber, which has a hard polymer coating that allows a high core-to-clad ratio and a 0.22 numerical aperture for efficient light coupling. It notes that the pure fused silica used in the core is made by reacting silicon tetrachloride with oxygen, using a plasma arc rather than an oxyhydrogen flame. This ensures that the residual hydroxyl concentration (OH) will be low in the core material, resulting in suitable infrared transmission. The sheet lists fiber features, specifications and applications and provides diagrams of a fiber cross section and a graph of typical spectral attenuation.