All-silica nonsolarizing optical fibers for UV medical applications

Abstract

Optical fibers and fiber bundles have been developed for UV applications in general but have specific benefits for UV applications within medicine such as excimer angioplasty and UV perforation of the heart wall in heart bypass operations. Optical fibers have been tested for transmission changes at 193 nm, 214 nm, 253 nm and 365 nm. Whereas standard synthetic silica optical fibers developed color centers within 10,000 pulses of 193 nm energy, the new CeramOptec fibers were observed to experience only minimal changes in attenuation after 100,000 pulses. Similarly under constant irradiation by a high power deuterium lamp only minor changes in the attenuation at both 214 nm and 253 nm were observed for the 'non-solarizing' UV fibers after 121 hours, whereas standard UV fibers lost up to 50% after only 24 hours of exposure. Fiber bundles have been produced which can stand up to the elevated temperatures experienced at the source end when strong UV sources are needed for specific applications. Test results and information on the testing as well as some information on the fibers tested is given below.