FLUORIDE GLASS OPTICAL COUPLER AND METHOD OF MANUFACTURE

摘要

A fused coupler is formed from two twisted optic fibres (2,3) of fluoride glass by heating them in the slot (18) of a temperature-controlled heater (15) in a shroud (14) containing an oxygen-free atmosphere. The glass of the fibres may be ZBLAN glass in which case the temperature is 323 DEG C +/- 10 DEG C. In an alternative embodiment the shroud is dispensed with and inert gas (nitrogen) is injected into a hole in the slot (18).