OPTICAL FIBER BUNDLE AND METHOD FOR MANUFACTURE THEREOF

摘要

An optical fiber bundle which comprises a gas-tightly sealed case having both ends being optically transparent and, tied and held therein together with hydrogen or heavy hydrogen, a plurality of optical fibers each having a core comprising a silica glass as a primary component and a clad comprising a silica glass containing fluorine added thereto, wherein the case has a volume 10 times or less that of the glass of the optical fiber; and a method for manufacturing the optical fiber bundle, which comprises a step of holding optical fibers in an atmosphere of hydrogen or heavy hydrogen, to thereby impregnate the fibers with hydrogen or heavy hydrogen, a step of placing the optical fibers as an optical fiber bundle into the case before the release of hydrogen or heavy hydrogen from the optical fibers, and a step of sealing the case gas-tightly, to hold the hydrogen or heavy hydrogen released from the optical fiber within the case. The optical fiber bundle is improved in the resistance to ultraviolet rays in the wavelength region of 150 nm to 250 nm, is free from the danger of explosion during the manufacture thereof and can be manufactured with ease at a low cost.