摘要
本文以4f光学相干成像系统为基础,研究了倾斜光照明物体的情况下,物体频谱的移动规律以及对最终成像的影响。首先,分析了典型物体的频谱,揭示了物体信息与其频谱分布之间的映射关系。其次,基于该衍射受限的成像系统,研究了在倾斜光照明物体的情况下,频谱整体的移动导致系统通频带的频谱成分发生了改变,从而引起成像结果变化的规律。模拟结果表明在单次倾斜光照明物体时,相干成像的结果比较复杂,一般是无法真正提高成像分辨率的;只有获取不同角度倾斜光照明情况下的像面复振幅分布或其频谱,通过融合形成一个包含更多高频成分的频谱,方能实现提高成像分辨率。本文把傅里叶光学中基本的概念和科研前沿相结合,帮助学生加深理解教学中的知识点,并着重体会知识点是如何运用于科研创新的过程。
Based on the 4f optical coherent imaging system,the displacement phenomenon of the Fourier spectrum of the object and the influence to the final imaging results are studied in case that the inclined plane wave illuminates on the object.Firstly,the Fourier spectrum of the typical objects is analyzed,revealing the relationship between the information of the object and its spectrum distribution.Secondly,based on the diffraction limited imaging system,the shift of the whole spectrum is studied with the inclined plane wave illuminated on the object,which leads to the change of spectrum component of the system and the change of the imaging result.The simulation results illustrate that the imaging situation is complex when the object is illuminated by just single-shot inclined illumination,which normally cannot really improve the imaging resolution.In order to improve the imaging resolution,the complex amplitude or the Fourier spectrum at the imaging plane with various incident angles are needed,and further fusing them to a new Fourier spectrum containing high-frequency components.The imaging result with fine information can be achieved after inverse Fourier transform dealing with the new Fourier spectrum.In this paper,the basic concepts of Fourier Optics and the frontier of scientific research are combined to help students deepen their understanding of the knowledge points in teaching,and more important to think over how to apply the knowledge in the process of scientific research and innovation.
作者
赵洁
王大勇
王云新
戎路
ZHAO Jie;WANG Dayong;WANG Yunxin;RONG Lu(College of Physics and Optoelectronics, Faculty of Science, Beijing University of Technology, Beijing 100124)
出处
《物理与工程》
2022年第1期143-149,154,共8页
Physics and Engineering
基金
北京工业大学研究性教学示范课程(光学)项目、国家自然科学基金(批准号:62075001、61675010)
北京市教委科技重点项目(批准号:KZ202010005008)资助。
关键词
傅里叶变换
光学相干成像
傅里叶频谱
移频超分辨成像
倾斜光照明
Fourier transform
optical coherent imaging
Fourier spectrum
super-resolution imaging based on Fourier spectrum shifting
inclined optical wave illumination
