Fiber Fabry-Perot (FFP) filters have been widely used in optical fiber communications, and insertion loss (IL) is one of its important characteristics. Based on theoretically analysis, factors related to IL were discussed. In order to investigate the IL of different structures, simulations are carried out with finite-difference time-domain (FDTD) algorithm. Comparisons are made between the optimized structure and full-size-mirror FFP filter, and fiber-inserted FFP filter as well. Simulation results demonstrated that the finite- size-mirror structure can confine the mode size of the open resonator, hence reduce the IL of FFP filter.
 Y. Wei, K. Hu, B. Sun and T. Wang, “All-Fiber Widely Wavelength-Tunable Thu-lium-Doped Fiber Ring Laser Incorporating a Fabry-Perot Filter,” Laser Physics, Vol. 22, No. 4, 2012, pp. 770-773. http://dx.doi.org/10.1134/S1054660X12040263
 D. Petrantonakis, G. T. Kanellos, P. Zakynthinos, D. Apostolopoulos, N. Pleros and H. Avramopoulos, “40- Gb/s 3R Burst Mode Regenerator Using Four Integrated MZI Switches,” IEEE Photonics Technology Letters, Vol. 19, No. 5, 2007, pp. 288-290. http://dx.doi.org/10.1109/LPT.2006.890051
 Y. Ji, S. Zheng, Z. Li, X. Jin, X. Zhang and H. Chi, “Tunable Fiber Fabry-Perot for Pm-Im Conversion and Efficiency Improvement Inradio-Over-Fiber Links,” Microwave and Optical Technology Letters, Vol. 52, No. 9, 2010, pp. 2090-2095. http://dx.doi.org/10.1002/mop.25389
 D. Marcuse and J. Stone, “Fiber-Coupled Short Fabry-Perot Resonators,” Journal of Lightwave Technology, Vol. 7, No. 5, 1989, pp. 869-876. http://dx.doi.org/10.1109/50.19128
 Y. Bao, K. Hsu, T. Q. Li, C. M. Miller and J. W. Miller, “Cascaded Fixed and Tunable Multiple-Fiber Fabry-Perot Filters and Fixed and Tunable Ferrule Alignment Fixtures for Fiber Fabry-Perot filters,” US Patent 6241397, 2001.
 Y. Jiang and C. Tang, “High-Finesse Micro Lens Optical Fiber Fabry-Perot Filters,” Microwave and Optical Technology Letters, Vol. 50, No. 9, 2008, pp. 2386-2389. http://dx.doi.org/10.1002/mop.23679
 J. Stone and D. Marcuse, “Ultrahigh Finesse Fiber Fabry- Perot Interferometers,” Journal of Lightwave Technology, Vol. 4, No. 4, 1986, pp. 382-385. http://dx.doi.org/10.1109/JLT.1986.1074739
 D. Marcuse,” Loss Analysis of Single-Mode Fiber Splices,” Bell System Technical Journal, Vol. 56, No. 5, 1977, pp. 703-718. http://dx.doi.org/10.1002/j.1538-7305.1977.tb00534.x
 H. Kogelnik and T. Li, “Laser Beams and Resonators,” Proceedings of IEEE, Vol. 54, No. 10, 1966, pp. 1312- 1329. http://dx.doi.org/10.1109/PROC.1966.5119