Optical fiber sensor technology is a new technology which is formed with the rapid development of optical communication. In optical communication system, optical fiber is the medium for long distance transmission of optical signal. When the light wave propagation in optical fiber, characteristics of light phase, frequency, amplitude and polarization characteristic parameters, due to the role of temperature, pressure, magnetic field, electric field, external factors and change, so can the fiber as sensor element, the detection result in the size of the light signal changes of various physical quantities, this is the optical fiber sensor.

The external factors caused by the change of optical fiber phase to detect the physical device, said phase modulation fiber optic sensor and other amplitude modulation sensor type, polarization modulation type, light type, such as a variety of optical fiber sensor.

Compared with other sensors, the characteristics of optical fiber sensor is:

(1) anti electromagnetic interference resistance, good electrical insulation properties, corrosion resistance, Ann quanke rely on, so it can be used in strong electromagnetic interference, inflammable, explosive, corrosive environment.

(2) high sensitivity, light weight, small volume, light path variable, with the broad applications of landscape and profound physical content.