NAA of copper contamination in the fabrication of a fluoride optical fiberpreform

Abstract

NAA was used to determine trace amounts of copper in the raw materials used for fabricating a fluoride optical fiber and its preform. Copper contamination remaining in the preform after fabrication was monitored during the whole preform fabrication process. Copper contamination from the experimental instruments was found to originate from a gold coated brass mold. It was also found that a high contamination of copper in the preform occurred within a thickness of 300μm from its surface.