利用单缝衍射装置探究照片中“星芒”的成因  

Study the Causes of the Diffraction Spikes in Some Photos with a Single Slit Fraunhofer Diffraction Device

作　　者：杨静 冯传蕾 闫小乐 张涛 YANG Jing;FENG Chuanlei;YAN Xiaole;ZHANG Tao(Department of applied physics,Xi'an University of Sciences and Technology,Shaanxi Xi'an 710054;Shaanxi Railway Institute,Shaanxi Weinan 714099)

机构地区：[1]西安科技大学理学院应用物理系,陕西西安710054 [2]陕西铁路工程职业技术学院,陕西渭南714099

出　　处：《大学物理实验》2019年第2期5-10,共6页Physical Experiment of College

基　　金：国家自然科学基金(11605133);陕西省科技厅项目(2018JQ1047);陕西省高校在线开放课程建设与研究项目(16MY21);2017年陕西省高等教育MOOC中心在线课程转化教改研究项目(17MZ16);西安科技大学教育教学改革与研究项目(JG16009)

摘　　要：利用单缝衍射装置探究照片中的星芒背后的光学原理。激光束分别在不同方向的单缝和不同的正多边形小孔衍射屏上发生衍射。光通过两个互相垂直的单缝得到"十"字形衍射图案,是光传播的独立性和叠加原理的体现。星芒可视为光通过不同方向的单缝时分别发生衍射形成的衍射图案的叠加。光在正三角形、正方形、正五边形和正六边形小孔的衍射屏上发生衍射,衍射图案与摄影师们用具有不同叶片的光圈的相机拍摄的星芒一致,更直接地证明星芒是光通过多边形的相机光圈时发生夫琅禾费衍射的结果。此实验有望在大学物理教学中开展。The optical principles behind the diffraction spikes in some photos are studied.The laser beam is diffracted on the single slits in different directions and the diffraction screens with different.A cross-like diffraction pattern was observed when light passed through two vertically placed single slit,which is the embodiment of the independence and superposition principle of light propagation.The diffraction spikes can be regarded as the superposition of diffraction patterns formed by diffraction on single slit in different directions.When light is diffracted on the screen with a regular triangle hole,a square hole,a regular pentagonal hole and a regular hexagon hole respectively,the diffraction pattern is consistent with that of the diffraction spikes in pictures taken by the camera with apertures of different blade count.It is proved more directly that diffraction spikes in pictures are caused by light diffracting(Fraunhofer diffraction) around edges of polygon camera apertures.This experiment is expected to be carried out in college physics teaching.

关 键 词：星芒 夫琅禾费衍射 单缝 正多边形小孔 

分 类 号：O436.1[机械工程—光学工程]