为了正确快速地进行超声三维图像重建，讨论了有限衍射波束三维脉冲回波成像新方法，即使用有限衍射阵列声束一次发射成像，不仅成像区域声束不会发生扩散，而且可得到高信噪比、高帧率的超声三维图像。针对成像后由获取的数据归一化形成的空间散乱数据场，提出了一种新的插值三维重建算法，该算法从散乱数据场中自动提取边界，首先构造出一个辅助曲面，然后通过一种特殊的Hermite插值，在数据点的矩形作用域集合内，对辅助曲面进行变形，进而得到最终的插值曲面。实验结果表明，由于该算法无须三角剖分，因而计算速度快，且光顺效果好。

In this paper, 3D pulse-echo imaging with limited diffraction array beams is presented. Because only one transmission is required to construct 3D images, and the entire transducer aperture is used and both the transmission and reception beams do not diverge over a large depth of interest. The images obtained with limited diffraction array beams have a higher SNR and high frame rate compared to images obtained with conventional focused beams. Data acquired is transformed into spatial scattered data by normalizing. A new algorithm of surface construction is proposed. An assistant surface is constructed on the base of boundary that being automatically extracted from the scattered data. In the aggregate of rectangle fields of data, the assistant surface is modified to get the final surface by a piecewise bicubic Hermite interpolation. In the experiment, computer simulation of the imaging method with limited diffraction array beams has been carried out. A plane wave is used. At the same time, a single surface is reconstructed with the new reconstruction method described in this paper. However, to confirm validity a sphere and a face data acquired by laser are used to reconstruct. Results show that the algorithm has run short time, good fairness, without triangulation.