Sakai J, Kimura T
Appl Opt. 1978 Sep 1;17(17):2848-53. doi: 10.1364/AO.17.002848.
A method is presented for calculating offset and tilt losses for fiber splices with axially symmetric arbitrary-index profiles by approximating the profile with a staircase function. This method is applied to a large-core dual-mode fiber with zero intermodal dispersion as well as to single-mode fibers with step- and parabolic-index profiles. When a splice loss of 0.2 dB is permitted, the normalized offset misalignment is found to be D(N) = 0.635 for the dual-mode fiber at normalized frequency v = 4.605 and a power-law exponent alpha = 4.5. The D(N) value compares favorably with the values 0.560 and 0.614 for conventional step- and parabolic-index single-mode fibers, respectively. The dual-mode fiber is superior to the step- and parabolic-index fibers with respect to permissible splice offset tolerances.
本文提出了一种通过用阶梯函数近似光纤轮廓来计算具有轴对称任意折射率分布的光纤熔接的偏移和倾斜损耗的方法。该方法适用于具有零模间色散的大芯双模光纤以及具有阶跃折射率和抛物线折射率分布的单模光纤。当允许熔接损耗为0.2 dB时，对于归一化频率v = 4.605且幂律指数α = 4.5的双模光纤，归一化偏移失准量为D(N)= 0.635。该D(N)值分别与传统阶跃折射率和抛物线折射率单模光纤的0.560和0.614值相比更具优势。在允许的熔接偏移公差方面，双模光纤优于阶跃折射率和抛物线折射率光纤。
