关键词: 单模光纤, 双折射, 波片

Abstract: Ordinary single-mode fiber optic polarization controllers are described, by using the stress linear birefringence induced by bending the fiber. The principle and design of fiber wave plates completely equivalent to fractional wave plates of classical optics is presented. Halfwave and quarterwave plates are made by coiling the optic fiber in loops . For 0.6328 fan laser light, optimal halfwave plate is obtained by coiling the fiber with diameter of 125μm in two turns of 2.2 cm radius, and optimal quarterwave plate is in one turn of 2.2 cm radius. Halfwave plate and quarterwave plate can be combined to control polarization of light to any states inside single-mode fiber by adjusting the angles of two such fiber coils. Because the devices have advantage of simplicity and compact and can be used in line, they are very useful in interferential fiber-optic sensors as a polarization controller to realize an all fiber system.

Key words: single-mode fibre, birefringence, wave plate