领结型和椭圆型保偏光纤的应力和模式分析

Analysis on stress and modal field of bow-tie and elliptical cladding polarization-maintaining optical fiber

应用有限元方法对领结型和椭圆型保偏光纤的热应力双折射特性和模式双折射进行了分析,给出了这两种保偏光纤的应力和双折射分布规律。对领结型保偏光纤,研究了纤芯的双折射和模式双折射随着应力区离纤芯距离的变化规律;对椭圆型保偏光纤,研究了纤芯的应力双折射和模式双折射随包层椭圆度的变化规律;分析了光纤应力区结构对纤芯双折射大小和均匀性的影响,并将应力诱导双折射与模式理论计算结果进行了比较。

Using finite element method, thermal stress characteristics and birefringence of stress-induced and modal fields of polarization-maintaining optical fiber (PMF) with bow-tie shape and elliptical cladding shape are analyzed. Stress and birefringence distribution of PMF are gave. Variation laws of fiber-core birefringence and mode birefringence with inner radii of stress regions to bow-tie shape PMF are demonstrated, and variation laws of fiber-core birefringence and mode birefringence with change of elliptical ratio of elliptical cladding PMF arc demonstrated. The effects of the stress domain structure of the fiber on stress birefringence and modal birefringence are investigated and compared .