An organic-inorganic hybrid material benefits from processing advantages of organics and high refractive indices of inorganics. We focus on a titanium oxide hydrate system combined with common bulk polymers. In particular, we target thin-film structures of a few microns in thickness. Traditional Beer-Lambert approaches for measuring optical losses can only provide an upper limit estimate. This sensitivity is highly limited when considering the low-losses required for mid-range optical applications, on the order of 0.1 cm-1. For intensity based measurements, improving the sensitivity requires an increase in the optical path length. Instead, a new sensitive technique suitable for simple planar thin films is required. A number of systems were modelled to measure optical losses in films of 1 micron thick. The presented techniques utilise evanescent waves and total internal reflection to increase optical path length through the material. It was found that a new way of using prism coupling provides the greatest improvement in sensitivity. In keeping the requirements on the material simple, this method for measuring loss is well suited to any future developments of new materials in thin-film structures.

Date Published: 2 November 2016
PDF: 1 pages
Proc. SPIE 9961, Reflection, Scattering, and Diffraction from Surfaces V, 99610J (2 November 2016); doi: 10.1117/12.2237132

Published in SPIE Proceedings Vol. 9961:
Reflection, Scattering, and Diffraction from Surfaces V
Leonard M. Hanssen, Editor(s)