Research On The Design And Application Of Single Longitudinal Mode Erbium-doped Fiber

Fiber laser as a representative of the third generation laser,possess small size,light weight,high power,low noise and excellent characteristics.However,with the development of science,many fields such as long distance distributed temperature/strain sensing,optical communication,frequency locking have a high requirement on fiber laser.The single longitudinal mode fiber laser gets the attention of researchers gradually because of its ultra-narrow bandwidth laser output and high output of power.The article designs a new type of single longitudinal mode erbium-doped fiber lasers using the combination of double cavity and saturable absorber to select laser longitudinal mode.First,Simulation software Optisystem is used to simulate the laser On the basis of analyzing the structure and the principle of the fiber laser.Secondly,the single longitudinal mode erbium doped fiber laser system is built,and Parameters such as output power,threshold was measured.Finally,a fiber laser is proposed and designed based on the sensing characteristics of the fiber laser.This paper mainly done the following aspects of research work: The basic working principle of erbium-doped fiber laser are analyzed,then a new type of structure of fiber laser is designed on this basis;The new structure of laser system is built on the simulation software,the effects of ring cavities and saturable absorber on laser output power,threshold and others parameters are studied;the parameters of the laser from the length of the saturable absorber and coupling ratio are optimized;Various types of data from the simulation are used to set up the fiber laser experiment platform.In the experiment,we implemented the laser output,parameters such as laser power,threshold was measured and compared with the numerical simulation analysis;An innovative point that the new structure of fiber laser has been applied to transformer winding temperature monitoring is put forward based on the sensing properties of the fiber laser high sensitivity,and verify the feasibility of the innovation points from the principle of transformer winding temperature monitoring,the fiber laser sensor features.Finally,the temperature monitoring system based on fiber laser has been designed.