Patent ID: 8705902

Claim:
An optical fibre sensor assembly comprising: a source of a plurality of different frequency substantially monochromatic signals; a modulator connected to the output of the source to produce a train of pulses of the monochromatic signals, and to output said train of pulses to an optic fibre; a plurality of in-fibre Bragg gratings, said in-fibre Bragg gratings arranged along said optic fibre; a plurality of sensor arrays, each array comprising a plurality of sensor elements, wherein the sensor elements in each array are optically addressed using said in-fibre Bragg gratings such that the signals produced by the array are of a respective monochromatic signal and each of said sensor arrays includes optical delays such that each sensor element in the array produces a different time delayed signal at its output with each signal being modulated by the respective sensor element, the modulation being the time taken by the signal to pass through the sensor element and be reflected by a reflective end of the sensor element; and an interrogation system, having a plurality of inputs connected such that each input receives the output signal from a respective sensor array, the interrogation system and associated sensor arrays being arranged such that the data from each sensor element can be resolved.