Characteristics of electric field from a coupled mode inside an optical fiber under perturbation by three-dimensional (3D) printed long-period fiber grating (LPFG) device have been observed in this work by the experiment and simulation. The various periodic index differences referring to the weights of perturbation by 3D printed LPFG device are applied on the single-mode fiber. The experimental results show that the resonant wavelength shift is a linear function of the grating period with the maximum coefficient of determination R² of 0.9995. Some of resonant wavelengths are chosen to run simulations to investigate the electric field distribution. The scattering direction of the electric field states the magnitude of leaking optical power when the light transmits through the grating region applied to the single-mode fiber. Both the experimental and simulation results demonstrate that our proposed scheme can usefully be applied to selective tunable filters, intruder sensors, etc.

中文翻译：

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3D打印长周期光纤光栅设备摄动的耦合模式特性

在这项工作中，通过实验和仿真观察到了在三维（3D）打印长周期光纤光栅（LPFG）设备的扰动下，来自光纤内部耦合模式的电场特性。涉及3D打印LPFG装置摄动权重的各种周期性折射率差异都施加在单模光纤上。实验结果表明，共振波长偏移是光栅周期的线性函数，最大确定系数为R ^2。为0.9995。选择一些谐振波长来进行仿真以研究电场分布。电场的散射方向表示当光透射通过施加到单模光纤的光栅区域时泄漏的光功率的大小。实验和仿真结果均表明，我们提出的方案可以有效地应用于选择性可调滤波器，入侵传感器等。