为在基于电磁式位置传感器的三维超声成像系统中 ,准确而快速地寻找到电磁式定位系统中接收器与图像平面间的空间关系 ,设计了一种利用三棱锥 /四棱锥模型的几何特性来计算定标参数的方案。这种新方法不仅减小了超声束在远场发散对定标精度的影响 ,而且提高了定标效率。物理实验证明系统在稳定性、三维重建精度和准确度方面具有良好的性能 In order to find the spatial relationship between the receiver and the image plane in the electromagnetic positioning system accurately and quickly in the three-dimensional ultrasonic imaging system based on the electromagnetic position sensor, a geometric feature using the model of the pyramid / pyramid was designed Calculation of calibration parameters of the program. This new method not only reduces the influence of ultrasonic beam divergence in the far field on the calibration accuracy, but also improves the calibration efficiency. Physical experiments show that the system has good performance in stability, three-dimensional reconstruction accuracy and accuracy