Quasi-distributed refractometer using tilted Bragg gratings and time domain reflectometry.
Tilted fiber Bragg gratings (TFBGs) have been demonstrated to be accurate refractometers as they couple light from the fiber core to the cladding. Because they require spectral measurements on several tens of nanometers, demodulation techniques reported so far are not suited for quasi-distributed refractive index sensing using TFBGs cascaded along a single optical fiber. We demonstrate here that a commercial Optical Time Domain Reflectometer (OTDR) can be used to multiplex identical TFBGs refractometers written in the same optical fiber. Our solution is simple, relatively fast, cost-effective and is particularly interesting for the monitoring of long structures.
Caucheteur
Christophe
C
Electromagnetism and Telecom Unit, Faculté Polytechnique de Mons, Mons, Belgium. christophe.caucheteur@fpms.ac.be
Wuilpart
Marc
M
Chen
Chengkun
C
Mégret
Patrice
P
Albert
Jacques
J