Method for stripping cladding light in the High power fiber laser

The output performance of large mode area (LMA) all-fiber laser are affected by the stripping ability of cladding light, which is consisting of the residual pump light and cladding mode signal light. The common method of stripping cladding light is to recoat the DCF (double clad fiber) with a high index gel, but it strips the cladding light quickly within the first few millimeters and makes the local temperature too high. In order to strip the power of cladding light uniformly over the length of the fiber, a method corroding the inner cladding layer to special shape is proposed. The Monte Carlo algorithm is used to simulate the performance of this method. The results show that it has the attenuation ability of 26 dB and can strip the cladding light uniformly without making local temperature too high.