安徽理工大学学报（自然科学版）
安徽理工大學學報（自然科學版）
안휘리공대학학보（자연과학판）
JOURNAL OF ANHUI UNIVERSITY OF SCIENCE AND TECHNOLOGY(NATURAL SCIENCE)
2014年
4期
6-9
,共4页
夫琅禾费衍射%快速傅里叶变换%图像分辨率
伕瑯禾費衍射%快速傅裏葉變換%圖像分辨率
부랑화비연사%쾌속부리협변환%도상분변솔
Fraunhofer diffraction%fast Fourier transformation ( FFT)%image resolution
通过对衍射屏透光函数进行二维傅里叶变换和离散型快速傅里叶变换，分别得到矩孔夫琅禾费衍射的光强分布的解析表达式和数值结果。然后借助Matlab软件强大的作图功能实现了两种情况下光强分布的可视化仿真，具体分析了衍射图像随矩形孔径大小的变化情况。最后通过将数值解和解析解直接比较，指出提高数值解图像分辨率保证结果有效可靠的关键性因素是对输入信号进行适当的补零。
通過對衍射屏透光函數進行二維傅裏葉變換和離散型快速傅裏葉變換，分彆得到矩孔伕瑯禾費衍射的光彊分佈的解析錶達式和數值結果。然後藉助Matlab軟件彊大的作圖功能實現瞭兩種情況下光彊分佈的可視化倣真，具體分析瞭衍射圖像隨矩形孔徑大小的變化情況。最後通過將數值解和解析解直接比較，指齣提高數值解圖像分辨率保證結果有效可靠的關鍵性因素是對輸入信號進行適噹的補零。
통과대연사병투광함수진행이유부리협변환화리산형쾌속부리협변환，분별득도구공부랑화비연사적광강분포적해석표체식화수치결과。연후차조Matlab연건강대적작도공능실현료량충정황하광강분포적가시화방진，구체분석료연사도상수구형공경대소적변화정황。최후통과장수치해화해석해직접비교，지출제고수치해도상분변솔보증결과유효가고적관건성인소시대수입신호진행괄당적보령。
The analytical expressions and numerical results of the rectangular Fraunhofer diffraction optical inten-sity distributions were obtained by using two dimentional Fourier transformation and discrete fast Fourier transfor -mation(FFT) respectively.Based on the powful drawing function of Matlab software , the visual simulation of the optical intensity in the above cases was realized .The change of the diffraction fringes was studied by adjusting the size of the rectangular aperture as well as the wave length of the incident plane wave .Finally, It was found out that zero padding around the aperture is necessary in order to improve the image resolution and guarantee the reliability of the numerical results .
