TITLE:
Semiconductor Optical Amplifier (SOA)-Fiber Ring Laser and Its Application to Stress Sensing
AUTHORS:
Yoshitaka Takahashi, Shinji Sekiya, Tatsuro Suemune
KEYWORDS:
Fiber Laser, Fiber Sensor, Ring Laser, Semiconductor Optical Amplifier, Optical Sensor
JOURNAL NAME:
Optics and Photonics Journal,
Vol.1 No.4,
December
7,
2011
ABSTRACT: We have developed a novel optical fiber ring laser using a semiconductor optical amplifier (SOA) as the gain medium, and taking advantage of polarization anisotropy of its gain. The frequency difference of the bi-directional laser is controlled by birefringence which is introduced in the ring laser cavity. The beat frequency generated by combining two counter-propagating oscillations is proportional to the birefringence, the fiber ring laser of the present study is, therefore, applicable to the fiber sensor. The sensing signal is obtained in a frequency domain with the material which causes the retardation change by a physical phenomenon to be measured. For the application to stress sensing, the present laser was investigated with a photoelastic material.