轴外点光源复振幅分布函数的讨论

在处理点光源球面波复振幅传播、交换等问题时,为了简化数学运算。通常应用菲涅耳近似,以二次曲面代替球面,但是,当离轴角较大时,菲涅耳近似的误差较大,明显地与实验现象不符。本文从点光源理想球面波复振幅分布函数出发,采用一种准菲涅耳近似,导出了轴外点光源复。振幅分布函数较为准确的简单表示式,该式同样能简化运算,而且还能满意地解释一些实验现象。

DISCUSSION OF OFF-AXIS POINT SOURCE COMPLEX AMPLITUDE FUNCTION

when the propagation and transformation of complex amplitude function(CAF)of point light source is dealed with,the Fresnel approximation is usually used withquadratic instead of spherical wavefront in order to simplify the mathematic operationWhen the off-axis angle of point source is large,this approximation is far apart from theexperiment phenomina,and the errors are evident. From the spherical CAF of ideal pointsource,a simple accurate CAF expression of off-axis point source is derived which cansatisfactorily explain the experimental phenomena in this article.