中文摘要：

为了促进具有体积小、功耗低、成像速度快等优点的透镜声呐在水下成像中的应用,选取了PMMA（polymethyl methacrylate）和PMP（polymethyl pentene）2种材料,利用混合模型设计并加工了单透镜系统和双透镜系统,对2个透镜系统分别进行了波束形成和目标成像试验研究.试验测得的焦点位置和波束图与仿真结果基本一致,从而验证了混合模型模拟透镜声场的有效性和准确性.得到了十字形和圆环2种目标的成像图,通过综合比较各种试验结果可知：PMMA是一种有效的透镜加工材料,透镜组合在缩短焦距方面具有优势,但同时增大了对声波的吸收,因此透镜组的设计要综合考虑这2方面的因素.

英文摘要：

The advantages of lens-based sonar include small volume,low power consumption and high-speed imaging.In order to promote the application of sonar in underwater imaging,two kinds of lens systems were designed,simulated,and then fabricated for this paper.One was composed of a single lens made from polymethyl methacrylate（PMMA）,and the other was composed of two lenses made from polymethyl pentene（PMP）.Beam-forming and object imaging experiments for the lens systems were conducted in water tanks.The focal positions and beam patterns measured in the experiments matched those in simulations.This proved the legitimacy of the hybrid geometric/wave acoustic model developed by the authors.In addition,images of objects with crossed or circular shapes were also tested.Based on the experimental results,PMMA was clearly the most effective material for a single lens.At the same time,multiple lens systems were found to have the advantage of a shorter focal length.This was counterbalanced by increased acoustic attenuation.Hence,multiple lenses system design must compromise on these two factors.