从损耗角度分析了影响非线性光纤器件性能的因素。讨论了插入损耗、回波损耗和固有损耗随入射光功率的变化规律。当在高功率情况下，受激布里渊散射(SBS)会导致非线性光纤的插入损耗随注入光功率线性增加，其斜率与SBS转换效率有关。比较了高非线性光纤缠绕在不同半径线盘时损耗的变化，以及它对SBS阈值和四波混频转换效率的影响。研究表明，高非线性光纤采用直径为7 cm的线盘缠绕时基本上不会影响非线性光纤器件的性能，这为设计沿光纤轴向提供磁场的螺绕环装置提供了重要参考，对下一步开展非线性磁光光纤特性的研究也有指导意义。

The key factors of nonlinear fiber devices are analyzed from the loss aspect. The dependences of insertion loss, reflection loss and intrinsic loss on the input optical power are studied. In the case of high input optical power, the insertion loss is proportional to the input optical power due to the stimulated Brillouin scattering (SBS), and the slope is related to the SBS efficiency. The changes of loss are measured in fiber spools with different diameters. The SBS threshold and the efficiency of four-wave mixing (FWM) in the fiber spool with small diameter are also investigated experimentally. The results indicate that the nonlinear performance of optical devices with a 7cm-diameter fiber spool is basically the same as that of the fiber spool with the conventional diameter, which helps to design the toroidal coil with the magnetic field along the fibers and analyze the characters of the nonlinear magneto-optic fiber.