| 摘要 |
PURPOSE:To seal an optical fiber introduction part securely by lowering pressure near a through hole at the opposite side of where molten metal is flowed in when the metal for sealing is flowed in a gap. CONSTITUTION:A mandrel 11 to which optical fibers 12 and 12' are adhered temporarily is run through the through holes 10b of a metallic block while a slight gas is left, and solid-state metal 13a for sealing is put in the recessed part 10c of the metallic block 10 near the mandrel 11 with the riser part 10a of the metallic block 10 up. In this state, the metallic block 10 is covered with a blind plug 16 and an evacuation nipple 17 is fitted to the lower side to produce a vacuum through a vacuum port 19. Then, when a sealed cavity container is evacuated to a specific degree of vacuum, a soldering gun 20 is heated from outside the metallic block 10c where the solid-state sealing metal 13a is placed so that the outer periphery of the blind plug 16 is all covered, thereby fusing the solid-state sealing metal 13a. |
