为减小分布反馈式（DFB）光纤激光器在水声探测时的扰动，设计了一种双膜片式封装结构的光纤激光水听器。该结构通过膜片增大声压作用面积，并转化为激光器的轴向应变以实现增敏。利用有限元软件ANSYS对该结构进行了仿真分析，加工制作了双膜片式结构封装的DFB光纤激光水听器原型样品，并对其进行了水声实验研究。实验测得，研制的双膜片端面增敏结构的DFB光纤激光水听器在2.5~10 kHz的平均声压灵敏度为-136.9 dB，波动幅度不高于±0.5 dB，水听器的工作频带向高频得到了有效拓宽，使其能很好地满足舷侧阵的工程化应用要求。

To reduce the fluctuation of a distributed feedback (DFB) fiber laser used in underwater sound detection, a fiber laser hydrophone of encapsulated structure with two diaphragms is designed. This structure increases the activated area of the acoustic pressure through the diaphragms, which is transformed to the axial strain in the fiber laser to realize the enhancement of the pressure sensitivity. After the structure is analyzed by ANSYS, the prototypes of the new kind of hydrophone based on the structure are fabricated and tested. Experimental results show that acoustic pressure sensitivity of the DFB fiber laser hydrophone reaches to -136.9 dB with the fluctuation less than ±0.5 dB in the frequency range of 2.5~10 kHz, which shows that the working frequency of the hydrophone is expanded to high frequency and it can well meet the requirements for the engineering application of flank array.