[1] [1] A. M. Vengsarkar, P. J. Lemaire, J. B. Judkins. Long-period fiber gratings as band-rejection filters［J］. J. Lightwave Technol., 1996, 14(1): 58～65

[2] [2] J. H. Chong, P. Shum, H. Haryono, A. Yohana et al.. Measurements of refractive index sensitivity using long-period grating refractometer［J］. Opt. Commun., 2004, 229: 65～69

[3] [3] Gu Zhengtian, Deng Chuanlu. Application and development of coated fiber grating［J］. Chinese J. Lasers, 2009, 36(6): 1317～1326

[4] [4] C. C. C. Lam, R. Mandamparambil, T. Sun et al.. Optical fiber refractive index sensor for chloride ion monitoring［J］. IEEE Sensors Journal, 2009, 9(5-6): 525～532

[5] [5] B. M. Lacquet, P. L. Swart, G. Ameerb. Long-period grating with sol-gel coating for CO2 detection［C］. SPIE, 2004, 5502: 287～290

[6] [6] M. Konstantaki, S. Pissadakis, S. Pispas et al.. Optical fiber long-period grating humidity sensor with poly (ethylene oxide)/cobalt chloride coating［J］. Appl. Opt., 2006, 45(19): 4567～4571

[7] [7] J. M. Corres, I. D. Villar, I. R. Matias et al.. Fiber-optic pH-sensors in long-period fiber gratings using electrostatic self-assembly［J］. Opt. Lett., 2007, 32(1): 29～31

[8] [8] X. W. Shu, X. M. Zhu, S. Jiang et al.. High sensitivity of dual resonant peaks of long-period fibre grating to surrounding refractive index changes［J］. Electron. Lett., 35(18): 1580～1581

[9] [9] X. W. Shu, D. X. Huang. Highly sensitive chemical sensor based on the measurement of the separation of dual resonant peaks in a 100-μm-period fiber grating［J］. Opt. Commun., 1999, 171: 65～69

[10] [10] Gu Zhengtian, Xu Yanping, Deng Chuanlu et al.. Dual peak resonance and transmission spectrum in coated long-period fiber grating［J］. Acta Optica Sinica, 2008, 28(2): 219～225

[11] [11] K. Kalli, H. L. Dobb, D. J. Webb et al.. Development of an electrically tuneable Bragg grating filter in polymer optical fibre operating at 1.55 μm ［J］. Meas. Sci. Technol., 2007, 18: 3155～3164

[12] [12] G. Nemova, R. Kashyap. Fiber-Bragg-grating-assisted surface plasmon-polariton sensor［J］. Opt. Lett., 2006, 31(14): 2118～2120

[13] [13] Y. J. He, Y. L. Lo, J. F. Huang. Optical-fiber surface-plasmon-resonance sensor employing long-period fiber gratings in multiplexing ［J］. J. Opt. Soc. Am. B, 2006, 23(5): 801～811

[14] [14] T. Erdogan. Cladding-mode resonances in short- and long-period fiber grating filters［J］. J. Opt. Soc. Am. A, 1997, 14(8): 1760～1773

[15] [15] D. Gloge. Weakly guiding fibers［J］. Appl. Opt., 1971, 10(10): 2252～2258

[16] [16] C. Tsao. Optical Fibre Waveguide Analysis［M］. New York: Oxford Press, 1992