Abstract: Solar resistant fused silica optical fiber is made by heating the starter rod, drawing the fiber, and preferably immediately diffusing hydrogen into the fiber, then promptly covering the hydrogen diffused fiber with hermetic coating to trap the hydrogen within the fiber. The presence of hydrogen in the fiber neutralizes UV radiation induced defects and because the hydrogen can only migrate through the fiber ends, the life of the solar resistant fiber for transmission wavelengths is increased by several years over conventional solar resistant fiber.

Abstract: A fiber optic, cylindrical, light diffuser for medical use includes an unclad distal fiber end where the exposed core end has a conical shape. The core end is enclosed by a sleeve which contacts the clad portion of the fiber only and defines a closed chamber with the distal end of the fiber. The chamber is filled with light diffusing material. The diffuser exhibits highly uniform output light distribution and is capable of carrying relatively high power densities safely.