Semiconductor Optical Amplifier (SOA)-Fiber Ring Laser for Sensor Application

A bi-directional fiber ring laser with a semiconductor optical amplifier has been developed in which a frequency difference between the counter-propagating oscillations is controlled by an introduced birefringent medium. With the material which causes the retardation change by a physical phenomenon to be measured, the laser in this study is applicable to a novel fiber sensor of which the sensing signal is obtained in a frequency domain.