OPTICAL FIBER LEAD-IN TERMINAL

摘要

PURPOSE:To facilitate leading the light into a vessel by providing a hole in a flange which is used to attach an optical fiber coated with a metallic film to the pressure vessel or the vacuum vessel and inserting the optical fiber through this hole and keeping airtightness between the optical fiber and the flange with a low-melting point metal. CONSTITUTION:An optical fiber 3 is coated with an Al metallic film of about 10mum thickness. In case that an optical fiber 3 is led into a vacuum vessel 1, a Pb alloy is melted by high frequency heating or the like and is packed in the gap between the hole and the optical fiber for the purpose of adhering the optical fiber 3 in the hole having 1mm diameter piercing a copper flange 2 and the flange to each other, thereby fixing the optical fiber and the flange. This flange 2 is attached to the vacuum vessel 1 to keep sufficiently the degree of vacuum in the vessel 1 at 10<-6>Torr.