Distributed Optical Fibre Sensing Technology

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Distributed optical fibre sensing uses an optical fibre as a transducer to continuously detect or measure a variable of interest along the entire length of the fibre. Crucially, the sensing system also provides the distribution of the values of the variable with their locations along the fibre. Common variables that are sensed include temperature, strain and acoustic waves or vibrations and the systems are often referred to by their respective acronyms as DTS (distributed temperature sensing), DSS (distributed strain sensing), DAS (distributed acoustic wave sensing) and DVS (distributed vibration sensing). 

When environmental changes occur near to the sensing fibre, the characteristics of the light propagating in that part of the fibre, such as the intensity, phase, frequency or polarisation of the light, can be changed and these changes can be detected in the interrogator. Once detected, these changes can then be converted to changes in the variable being sensed.