Pressure and measurement by means of an optical fiber

摘要

An optical fiber (FD) that can be used for measuring pressure is arranged as follows. The optical fiber (FD) comprises a core (CO) and a cladding (CL) surrounding and contacting the core (CO). A stress-applying arrangement (SE1, SE2), which is embedded in the cladding (CL), applies constant anisotropic stress on the core (CO). This causes the core (CO) to exhibit a deformation. A pressure conversion arrangement (HO1, H02), which is also embedded in the cladding (CL), converts isotropic external pressure applied to the optical fiber (FD) into pressure-dependent anisotropic stress applied to the core (CO). The pressure conversion arrangement (HO1, H02) is disposed with respect to the stress-applying arrangement (SE1, SE2) so that the pressure-dependent anisotropic stress enhances the deformation of the core (CO) caused by the constant anisotropic stress.

主权项

1. An optical fiber (FD) comprising:
a core (CO); a cladding (CL) surrounding and contacting the core, a pressure conversion arrangement (HO) embedded in the cladding for converting isotropic external pressure applied to the optical fiber into pressure-dependent anisotropic stress applied to the core, the pressure conversion arrangement being disposed with respect to a stress-applying arrangement so that the pressure-dependent anisotropic stress enhances the deformation of the core caused by the constant anisotropic stress a hollow stress-applying arrangement (SE) embedded in the cladding for applying constant anisotropic stress on the core wherein the pressure conversion arrangement (HO) is comprised within the hollow stress-applying arrangement (SE); andwherein:
the stress-applying arrangement comprises a pair of rod-like stress-inducing elements (SE1, SE2) disposed longitudinally and symmetrically with respect to the core (CO); or the pressure conversion arrangement comprises a pair of rod-like holes (HO1, HO2) disposed longitudinally and symmetrically with respect to the core.