Kashima N, Uchida N
Appl Opt. 1977 May 1;16(5):1320-2. doi: 10.1364/AO.16.001320.
Experiments have been performed to evaluate the increase in loss due to an outer layer around the cladding in a multimode step-index fiber composed of core and cladding. Liquid has been used to simulate the outer layer. Measured excess loss for each mode group is in agreement with our previously developed electromagnetic theory. Total excess loss for all guided modes existing in the fiber has also been measured by varying the mode power distribution, the refractive index of the outer layer, the cladding thickness, and the wavelength. Results are found to be in good agreement with the theory, and it is concluded that the theory is correct.
已进行实验来评估在由纤芯和包层组成的多模阶跃折射率光纤中，由于包层周围的外层导致的损耗增加。已使用液体来模拟外层。每个模式组的测量额外损耗与我们先前开发的电磁理论一致。还通过改变模式功率分布、外层折射率、包层厚度和波长，测量了光纤中存在的所有导模的总额外损耗。结果发现与理论非常吻合，并且得出结论该理论是正确的。
