两偏振模之间的色度色散差会对干涉信号产生很大影响wenxian.pdf

1244 JOURNAL OF LIGHTWAVE TECHNOLOGY, VOL. 23, NO. 3, MARCH 2005 Interference Between Two Orthogonally Polarized Modes Traversing a Highly Birefringent Air-Silica Microstructure Fiber Nori Shibata, Member, OSA, Akimichi Nakazono, and Yoshinori Inoue Abstract—Highly birefringent fibers can be used as polariza- Internal rotation is measured in fiber-optic gyros as the phase tion-maintaining fiber in interferometer fiber optic gyros and in difference between two beams traveling in opposite directions pressure sensors. Interference between two orthogonally polarized around a fiber-optic sensing loop, and a broadband light source modes traversing a highly birefringent air-silica microstructure fiber is investigated theoretically and experimentally. The theory such as a super luminescent diode (SLD) is normally used includes the effect of the dispersive nature of the modal birefrin- [18]. Considering a fiber-optic gyro employing an SLD and gence of highly birefringent fiber. Measurements are conducted a PM fiber, interference between the two counterpropagating using super luminescent diodes operating at the center wave- beams may be influenced by the dispersive nature [21], [22] lengths of 846 and 973 nm with spectral half-widths of 7.4 and 8.1 of the modal birefringence even when the PM fiber is part nm, respectively, and a 9-m highly birefringent fiber. Experiments yield interference fringe visibility values of 0.4–0.5, even when of the interferometer fiber-optic gyro [15]. The influence the effective optical path difference between the two modes is arises when the two beams polarized along fast and slow axes zero. The theory well