A supplier of glass tubing and optical fibers for the medical industry has developed a new line of high-purity glass optical fibers with physical and chemical properties designed to improve on the performance of existing glass fibers in medical device applications. These environmentally friendly optical fibers are distinguished by their good transmission of white light, long lifetime, and lead-, arsenic-, and antimony-free formulation. Because of the fibers’ low color shift, illuminated objects retain their natural color even if the fibers are used in long light guides. A generous numerical aperture enables such light guides to capture more light from the beginning, and low attenuation in the visible range results in higher light output at the end of the guide. The fibers’ durability in the face of autoclaving or cleaning for reuse is attributable to their good chemical stability and low solarization. Optimized light transmission near the ultraviolet range makes the fibers suitable for fluorescence-based applications in medical diagnostics.