大学物理 ›› 2021, Vol. 40 ›› Issue (8): 45-.doi: 10.16854 / j.cnki.1000-0712.200492

• 物理实验 • 上一篇    下一篇

数值法研究光的圆孔衍射实验现象

曹冬梅,曾祥梅   

  1. 1. 延安大学 物电学院,陕西 延安 716000; 2. 西安邮电大学 电子工程学院,陕西 西安 710121
  • 收稿日期:2020-11-04 修回日期:2020-12-14 出版日期:2021-08-20 发布日期:2021-08-30
  • 作者简介:曹冬梅( 1974—) ,女,陕西榆林佳县人,延安大学物电学院副教授,硕士,主要从事光学方面的教学与研究工作.
  • 基金资助:
    陕西省教育厅项目( 18JK0723) 资助

Study on the experimental phenomenon of light diffraction by a circular aperture with numerical method

CAO Dong-mei¹,ZENG Xiang-mei²   

  1. 1. School of Physics and Electronic Information,Yan’an Univeristiy,Yan’an,Shaanxi 716000,China; 2. School of Electronic Engineering,Xi'an University of Posts and Telecommunications,Xi'an,Shaanxi   710121,China
  • Received:2020-11-04 Revised:2020-12-14 Online:2021-08-20 Published:2021-08-30

摘要: 在平行平面波近似的情况下,数值法求解菲涅耳-基尔霍夫衍射积分公式,得到平行平面光波通过圆孔衍射后的光强分布图.

通过对纵向及横向光强分布图的数值分析,验证了轴上点光强由菲涅耳数决定,菲涅耳数大于 1 时为菲涅耳衍射区,菲涅耳数小于 1 时为夫琅禾费衍射区. 在近场,光强分布为明暗相间的环形条纹;在远场,光束演化成束腰位置在圆孔处的高斯光束,仿真结果与理论和实验结果基本一致. 本仿真结果将光衍射的抽象理论直观化、可视化.

关键词: 数值法, 圆孔衍射, 菲涅耳数, 高斯光束

Abstract: In the case of parallel plane wave approximation,the Fresnel-Kirchhoff diffraction

integral formula is solved numerically,and the light intensity distribution diagram of the

diffraction through the circular aperture is obtained. Through the numerical analysis of the

longitudinal and transverse light intensity distribution diagrams,it is

concluded that the intensity of the light on the axis is determined by the Fresnel number. When the

Fresnel number is greater than 1,it is the Fresnel diffraction zone,and when the Fresnel number is less than 1,it

is the Fraunhofer diffraction zone. In the near field,the intensity of the light distribution is a

ring-shaped stripe of bright and dark; in the far field,the beam evolves into a Gaussian beam with

a waist at the circular hole. The simulation results are

basically consistent with the theoretical and experimental results. The light diffraction theory is

visualized intuitively with the simulation results.

Key words: numerical method, circular aperture diffraction, Fresnel number, Gaussian beam