| 摘要 |
PURPOSE:To preclude thermal deformation such as the burning of the jacket of an optical fiber by using a plasma arc and laser luminous flux with low energy density, and repeating spot welding and forming a continuous airtight weld zone. CONSTITUTION:When optical fiber including metallic jacket pipes 2 and 4 where optical fibers 1 and 3 are inserted while gaps are formed with the internal walls of the metallic jacket pipes are connected by a welding method through a metallic connecting pipe 5, the plasma arc and laser luminous flux with low energy density are used and spot welding is repeated as shown by 7 - 16 to form the cintinuous airtight weld zone. In this case, the welding is carried out, spot by spot, in a short time, so the weld zone is cooled speedily in a half time to hold the mean temperature of the weld one invariably low and the optical fibers are held at a distance from the weld zone, so that the value of heat conducted to the optical fiber surfaces is extremely small. Consequently, the thermal damage of the jackets which are not tolerant to heat so much can be evaded. |
