对反射型非本征F-P干涉型(Extrinsic Fabry-Perot Interferometer,EFPI)光纤传感器的损耗特性进行了分析,表明当腔长小于100 μm时,随着腔的变长光能量耦合损耗迅速增加;在考虑腔损耗的情况下,分析了如何合理选择两反射面的反射率以使输出光强的对比度达到*大;通过分析在制作F-P腔的过程中影响腔长变化的原因,总结出了一个可以准确控制和调整腔长的方法;依以上规则制作了F-P光纤传感器,并进行了实验验证｡ Analysis of Loss and Development of Fabry-Perot Optical Fiber Sensor GUO Zhen-wu,LI Wei-xiang,GUO Zhuan-yun,SUN Gui-ling,WANG Wen-bo (College of Information Technical Science , Nankai University,Tianjin 300071,China) Abstract:There is intensity loss when the light pass through the cavity of Extrinsic Fabry-Perot Interferometer.This paper studied the characteristic of intensity loss,and then presented the relationship between loss coefficient and the length of the cavity.The loss becomes larger rapidly with the cavity length becoming longer.When the output-signal-contrast reaches it's maximum,the relationship between the two end faces reflection index has been given.A method to control and adjust the length of the cavity is implemented. Key words:optical fiber sensor;fabryperot interferometer;intensity loss;length of cavity