On the assumption that there was a small solid sphere in the focusing area, the scattering field of concave sphere ultrasonic transducer was analyzed. 以凹球面超声换能器为研究对象，假设聚焦区存在一刚性球形微粒，对此时的散射场进行分析。
From the Fourier space K corresponding to the scattering field of the object, an imaging evaluation mechanism based on the spatial spectral coverage is proposed. 摘要从物体散射场对应的傅里叶空间出发，提出基于空间谱域分布的成像系统定性评价体系。
