离焦情况下波带片衍射光强的数值计算

基于非傍轴近似下菲涅耳 -基尔霍夫积分公式 ,讨论了波带片在离焦条件下的光斑特性 .通过数值计算 ,分别得到了在小离焦量和大离焦量时光强沿光轴径向的分布曲线、中心光斑的大小以及在特定范围内总能量随离焦量的变化规律 .为实际工作中应用波带片提供了更好的理论依据 .

Calculation of Diffraction Intensity of Zone Plate on Misfocus Condition

In the non- axis approach,the characters of the light spot of zone plate were investigated by us- ing the Frensnel- Kirchhoff integrating formula.Through the numerical simulation,the intensity distribu- tions along axis and along radius were shown in different misfocus conditions.Finally,allowable limit of the largest focusing error and the energy distribution of the light spot was given.The results provide a theoretical foundation for the applying of zone plates.