Study of the Induced Birefringence in the Single-mode Optic Fiber
单模光纤在通常情况下可以认为是不存在双折射现象的。但当光纤受到弯曲、侧压及扭转时 ,由于光弹效应使得光纤分别产生了线性双折射和圆振双折射。该文对单模光纤由于各种作用产生的诱导双折射进行了论述 ,推导了不同情况下双折射的计算公式 ,并分析了其中的差别。同时 ,还初步分析了实际系统中对各种双折射效应的应用。In a general way, it is considered that the single-mode optic fiber has no birefringence. But once the single-mode optic fiber is bent, clamped or twisted, the externally applied stresses can lead to induced birefringences through the photoelastic effect. This paper discusses the induced birefringences, one kind of which is linear birefringence, induced by bending or lamping the fiber, while another is circular birefringence, induced by twisting the fiber. Based on the photoelastic effect, the formulas in different conditions are presented. Furthermore, the applications of those formulas in real system are mentioned.