Study On Fiber Laser Combining Technology

Fiber laser is widely applied in scientific research, military matters, medicine, industry and other fields based on fine Laser beam, high efficiency, stable system, good heat dissipation, small volume and light weight. However, the increase of laser power and appearance of a series of physical mechanisms, such as nonlinear effects of doped fiber, thermal lens effects and so on, the output power of single fiber laser can’t be increased infinitely. So, fiber laser combining technique becomes a very effective way to raise the fiber laser power. In this paper, a theoretical analysis and experimental study on coherent combination and incoherent combination are discussed. A theoretical model of Transmission Volume Bragg Grating is built based on Kogelnik coupled wave theory, the optimized parameters of Transmission Volume Bragg Grating by numerical simulation are obtained. The simulation research on combination efficiency of incoherent two-way fiber laser is presented. The results showed that under the circumstance of the narrow spectral width and small divergence angel of light beam, the diffraction efficiency in theory is up to more than95percent. By setting up and optimizing a two-way all fiber laser coherent combining system,2.278Watts combining power and93.8percent combing efficiency are obtained finally.