Its principle is discussed, taking the divergent optical beam emitted from the fiber into consideration, which causes a loss factor for the effective reflectance.
考虑到光纤出射光束的发散，在有效反射率中引入了损耗因子，讨论了它的基本工作原理。
2
An interaction factor is introduced to deal with the multiple reflectance between the atmosphere and the underlying surface.