双半透镜干涉场的研究  

Investigation on the interference fields by bihalf-lens

作　　者：钟锡华[1] 张海君[1] 刘有菊[1,2] 

机构地区：[1]北京大学物理学院,北京100871 [2]保山师范高等专科学校物理系,云南保山678000

出　　处：《大学物理》2009年第7期5-9,共5页College Physics

摘　　要：基于波前分析和基尔霍夫衍射积分式,导出了在会聚球面波照射下圆孔或半圆孔菲涅耳衍射场沿轴的复振幅分布,特别关注其相位分布,给出了像点两侧对称点之间的相位差公式,结果表明过像点的相位变化是连续的.进而将这些结果应用于双半透镜装置,即梅斯林干涉实验,分别两种情况(即焦距相等而物距不等和物距相等而焦距不等)给出了分别由单个半透镜产生的两个衍射场之间的相位差公式和相应的干涉强度公式.结果表明,这两个衍射场沿轴的有效相位差未必是0,亦未必是π,还可能出现锯齿型的反复变化.本研究为正确地分析双半透镜产生的两个衍射场之间的干涉场提供了一个可靠的理论途径.Based on the method of wavefront analyses and the Kirchhoff diffraction integral expression, we derive the complex amplitude distribution along axis of Fresnel diffraction fields by a circular aperture or a half-circular aperture, which is illuminated by a convergence spherical wave. The phase distribution is especially focused and the phase difference formula between both symmetrical points beside the image point is given. The result shows that the phase change pass through the image point is continuous. Then the present result is applied to the bihalf-lens i. e. , the Meslin interference experiment. The phase difference formula as well as the intensity distribution between two diffraction fields respectively by a single half-lens are shown under two different situations, one is the focal lengths equal while the object distances not equal, another is the object distances equal while the focal lengths not equal. The results lead to a conclusion： the effective phase difference along axis between both two diffraction fields may be not equal to zero or π, it is also possibility to arise a change of this phase difference as a sawtooth form. This study provides a reliable theoretical way to exactly analyze the interference field from two diffraction fields by bihalf-lens.

关 键 词：菲涅耳衍射 菲涅耳-基尔霍夫衍射积分式 波前相因子分析 双半透镜干涉 

分 类 号：O436.1[机械工程—光学工程]