For EDFA and Raman pumping application, a fiber pigtail that integrates a 9xx/14xxnm FBG and a fiber lens is commonly used in the pump laser.

The fiber lens is used to couple light from the laser diode, and with good matching between the divergence of laser chip and fiber lens, coupling efficiency as high as 90% could be achieved. The FBG is used to form an external feedback structure, which will stablize the output laser around the center wavelength of the FBG, and meanwhile narrow the laser output spectrum. Besides, due to the low thermal dependence of FBG, the thermal stability of the laser output is also greatly improved. Therefore, high pumping efficiency as well as good pumping stability of the pump laser could be achieved.

Raysung is one of the only manufacturers in the world who have the cpability to manufacture both FBG and lensed fiber. By delivering the turn-key solution, Raysung help the customer to greatly reduce the cost.