紫外光纤光栅的包层模造成的损耗限制了光栅在波分复用系统中的使用。文章分析了同时具有下陷内包层和光敏内包层的光敏光纤可以极大地抑制包层模耦合，并采用 ＭＣＶＤ工艺制作出了硼和锗共掺（Ｂ／Ｇｅ）的带光敏的下陷内包层的光纤，经写入紫外光纤光栅证实该光敏光纤确实极大地抑制了包层模耦合。 The loss caused by the cladding mode of the UV fiber grating limits the use of the grating in the WDM system. The article analyzes that the photosensitive optical fiber with both the depressed inner cladding and the photosensitive inner cladding can greatly inhibit the cladding mode coupling, and the MCVD process has been used to fabricate the boron and germanium co-doped (B / Ge) photosensitive subsidence cladding optical fiber , Written into the UV fiber grating confirms that the light-sensitive fiber does greatly inhibit cladding mode coupling.