The Nanoworld of Contact Lenses Seen through Quantum Beams : Visualizing Surfaces

Abstract

We have involved in analyzing the surface chemical state of contact lenses by analysis techniques using quantum beams, such as synchrotron radiation and neutron sources. In this process, we have realized the importance of clarifying the analysis depth of each of these analysis techniques and the effectiveness of making use of the difference in the analysis depth among these techniques in the surface analysis of contact lenses. In this article, we report about our research on the analysis depth of the hard X-ray photoelectron spectroscopy (HAXPES) for the contact lens materials, and about the analysis of contact lens surfaces by X-ray absorption fine structure (XAFS) spectroscopy using surface-sensitive conversion electron yield (CEY) and bulk-sensitive partial fluorescence yield (PFY) modes, which have been performed at several experimental facilities.