Protective cladding for a mono-mode directional coupler

摘要

The protective cladding for a mono-mode directional coupler made of at least two incoming and outgoing fiber optic waveguides which are fused to one another along a coupling segment comprises at least two open cladding parts which can be connected to form a tube-shaped cladding. The material of the cladding parts has the same coefficient of expansion as the waveguide material of the mono-mode directional coupler. The protective cladding, being mechanically tightly connected with the incoming and outgoing fiber optic waveguides while leaving open the coupling segment of the mono-mode directional coupler, is closed off in a gas-tight manner such that in the case of temperature changes, there are no mechanical tensions in the coupling segment.