| 摘要 |
PURPOSE:To eliminate the deterioration and strength deterioration of optical fibers and to improve the transmission characteristic thereof welding the optical fibers to each other via low melting glass layers formed on the outside periphery of the clads of the respective optical fibers. CONSTITUTION:The cores 6a, 6b of the optical fibers 5a, 5b consist of germanium-doped quartz and the clads 7a, 7b consist of pure quartz. The low melting glass layers 8a, 8b consisting of the boron-doped quartz having the m.p. lower than the m.p. of the clads 7a, 7b are formed on the outside periphery of the clads. The optical fibers 5a, 5b are circumscribed with each other and the low melting glass layers 8a, 8b are welded in the circumscribed parts to bundle the fibers. A coating layer 9 consisting of a silicone resin is formed on the outside periphery. The respective low melting glass layers can be welded at the temp. below the temp. at which the clads, etc. are deformed in the stage of welding the optical fibers and therefore the cores and clads are kept internally strain-free and the out of roundless of the cores and clads is maintained. The deterioration in the transmission characteristic and strength is thus averted. |
