[1] [1] Patrick H.J., Chang C.C., Vohra S.T.. Long period fibre gratings for structural bend sensing[J]. Electron. Lett., 1998, 34(18):1773～1775

[2] [2] Wang Yiping, Rao Yunjiang, Zeng Xiangkai et al.. Bending characteristics analysis of long-period fiber gratings using coupled-mode theory[J]. Acta Photonica Sinica, 2002, 31(10): 1205～1208

[3] [3] Ueyn L.Block , Dangui Vinayak, Digonnet J.F. Michel et al.. Origin of apparent resonance mode splitting in bent long-period fiber gratings[J]. J. Lightwave Technol., 2006, 24(2): 1027～1034

[4] [4] Ivanov Alexei, Albert Jacques. Bent tilted fiber Bragg gratings for temperature-independent vibration sensing in vehicles[J]. SPIE, 2007, 6758: 675803-1～8

[5] [5] Zhou Jinlong, Dong Xiaopeng, Shi Zhidong. Theoretical and experimental investigation of the bending sensitivity of the D shaped fiber Bragg gratings[J]. Acta Photonica Sinica, 2006, 35(11): 1734～1737

[6] [6] He Zonghu, Zhu Yinian, Du Henry. Effect of macro-bending on resonant wavelength and intensity of long-period gratings in photonic crystal fiber[J]. Opt. Express, 2007, 15(4):1804～1810

[7] [7] Wang Yiping, Rao Yunjiang. A novel long period fiber grating sensor measuring curvature and determining bend-direction simultaneously[J]. IEEE Sensors Journal, 2005, 5(5):839～843

[8] [8] Martinez A.,Lai Y. , Dubov M. et al.. Vector bending sensors based on fibre Bragg gratings inscribed by infrared femtosecond laser[J]. Electro. lett., 2005, 41(8): 472～474

[9] [9] Erdogan Turan. Fiber grating spectra[J]. J. Lightwave Technol., 1997, 15(8):1277～1294

[10] [10] Qian Jingren. Coupled Mode Theory[M]. Textbook for graduate students in University of Science and Technology of China

[11] [11] Marcuse Dietrich. Field deformation and loss caused by curvature of optical fibers[J]. J. Opt. Soc. Am., 1976, 66(4): 311～320

[12] [12] Vassalo Charles. Optical Waveguide Concepts[M]. Elsevier Science Publishers. 1991

[13] [13] Lui Wayne, Xu Chenglin, Hirono Takuo et al.. Full-vectorial wave propagation in semiconductor optical bending waveguides and equivalent straight waveguide approximations[J]. J. Lightwave Technol., 1998, 16(5): 910～914

[14] [14] Feng Ningning, Zhou Guirong, Xu Chenglin et al.. Computation of full-vector modes for bending waveguide using cylindrical perfectly matched layers[J]. J. Lightwave Technol., 2002, 20(11):1976～1980

[15] [15] Ulrich R., Rashleigh S.C., Eickhoff W.. Bending-induced birefringence in single-mode fibers[J]. Opt. Lett., 1980, 5(6):273～275

[16] [16] Fallahkhair Arman B., Li Kai S, Murphy Thomas E. Vector finite difference mode solver for anisotropic dielectric waveguides[J]. J. Lightwave Technol., 2008, 26(11):1423～1431

[17] [17] Bertholds A., Dandliker R.. Determination of the individual strain-optic coefficients in single-mode optical fibres[J]. J. Lightwave Technol., 1988, 6(1):17～20