A biocompatible fiber tip will be developed from fluorophosphate (FP) glass for use with the 2.9-um Er:YAG laser. When coupled to a longer trunk fiber, this tip allows precise and char-free cutting and ablation inside the eye and at other sites in the body. During Phase I, the fiber transmission was improved from 60% to 70% at 2.9 microns over a 4 inch length. Power handling was also improved to over 6 Watts, and methods of strengthening the fiber were investigated. The fiber tip was used with an Er:YAG laser to ablate both soft and hard tissue samples. During Phase II, the transmission, strength, and power handling of the FP fiber tip will continue to be improved by reducing OH impurities, glass composition studies, and chemical etching of the preform. In addition, methods of scaling up production, such as the double-crucible technique, will be developed. Various tip geometries will be fabricated and the interaction with both soft and hard tissue samples will be studied.
