Patent ID: 8427651

Claim:
An optical sensor system comprising: an optical waveguide having a hollow core, wherein a first portion of the optical waveguide is configured to receive a first portion of an optical signal and a second portion of the optical waveguide is configured to receive a second portion of the optical signal, wherein the first portion of the optical signal propagates within the hollow core from the first portion of the optical waveguide to the second portion of the optical waveguide and the second portion of the optical signal propagates within the hollow core from the second portion of the optical waveguide to the first portion of the optical waveguide; and an optical coupler configured to combine the first portion of the optical signal and the second portion of the optical signal after the first portion of the optical signal and the second portion of the optical signal have propagated through the optical waveguide between the first portion of the optical waveguide and the second portion of the optical waveguide.