Study on Ti content in Low thermal expansion silica glass based on IR reflectance spectra

Abstract

Ultra-Low thermal expansion (ULE) silica glass with essentially zero coefficient of thermal expansion is one of the most promising achievements in glass technology in a few decades. The property of the low thermal expansion coefficient makes it a suitable candidate for optical systems to be used in critical environments like space or vacuum. In this paper, by the help of ICP-OES and Infrared reflectance spectra, we measured titanium content of different samples and its corresponding reflection spectrum. We compared the linear fitting relation of Ti content with reflectivity and of Ti content with integration area of Gaussian fitting peak with a weighted average wave centre in 923cm-1. Results show that the latter one has a better correlation coefficient. By the tests of the IR reflectance spectrum of samples, we can deduce the Ti content using the linear fitting result.