球面波的相奇异分布区域特征

Characteristics of the Phase Anomaly Zones of Spherical Waves

从波动方程出发 ,在基尔霍夫边界条件下 ,根据积分的物理意义 ,简明地研究了发散和汇聚球面波的相奇异区域分布。结果表明 ,除了汇聚的球面波焦点区域存在相奇异现象外 ,焦点以外的区域及对发散的球面波同样存在相奇异现象。发散球面波的相奇异区位于入射空间 ,在相奇异区域的不同部分相奇异规律不同 ,源点是相奇异区里的一个特殊点。汇聚的球面波的相奇异区域存在于像空间 ,结构简单 ,焦点是相奇异区域里的一个特殊点。

The phase anomaly zones are investigated on the basis of the integral theorem of Helmholtz and Kirchhoff in terms of the Kirchhoff′s boundary conditions and the physical meaning of the integral for the diverging and converging spherical waves. For the diverging spherical wave, the phase anomaly zone exists in the source space, the phase variations is different in the different parts of the zone, and the point source is a special point of the zone. On the other hand, the phase anomaly zone is in the image space, the phase variation is consistent in all the zones, and the focus is a special point of the phase anomaly zone for the converging spherical wave.