Patent ID: 7197217

Claim:
A method of making a fiberoptic light guide for use in curing photocurable materials, comprising the steps of: inserting a bundle of closely-packed, elongate optic fibers into a hollow glass cladding having a predetermined lead content; heating and drawing said cladding and optic fibers, after said inserting step, to fuse said bundle of optic fibers together and to seal said bundle of optic fibers within said cladding thereby forming an elongate fused fiberoptic rod; and placing said fused fiberoptic rod in a furnace and heating said rod to a predetermined temperature in an atmosphere of substantially 100% hydrogen gas thereby blackening said cladding by chemical reduction such that an outer peripheral surface of said fused fiberoptic rod formed by said cladding and extending lengthwise about said bundle of optic fibers is blackened along the length of said fused fiberoptic rod.