| 摘要 |
PURPOSE:To prevent the increment of optical absorption due to irradiation of radiation, by heating optical fibers. CONSTITUTION:Optical fibers 13 where clads 12 consisting of materials having a low refractive index are coated on outside circumferenctial faces of cores 11 consisting of glass materials having a high transmittivity are stored in a sheath 14 together with a conductive heating body 16. The conductive heating body 16 consists of materials having a high electric resistance, and a heat resisting insulating coating 17 is stuck to the outside circumference of the heating body 16. A cushion material 15 consisting of materials having a high heat conductivity is packed in gaps between optical fibers 13 and the conductive heating body 16. A current is flowed to the conductive heating body 16 to heat, and this heat is transmitted to optical fibers 13 through the cushion material 15 to heat them. |
