Surface tension and viscosity measurement of optical glasses using a scanning CO₂ laser

Abstract

We present a novel technique that can rapidly and accurately measure surface tension and viscosity by direct thermal processing of an optical fiber. We demonstrate the applicability of this technique for a variety of glass compositions from silica to soft glass fibers, and these results have been validated against results obtained with other techniques. In addition, this characterisation technique has been used to measure the surface tension and viscosity for previously unmeasured glass compositions. The techniques are ideal for acquiring critical parameters of relevance to the conditions for the controlled fabrication of new glass compositions into microstructured fibers. © 2012 Optical Society of America.