关键词: 厚样品/
三维叠层衍射成像/
迭代算法/
多波长
English Abstract
Experimental study on three-dimensional ptychography for thick sample
Pan An1 3,Zhang Xiao-Fei2 3,
Wang Bin2 3,
Zhao Qing1 3,
Shi Yi-Shi3 4
1.Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an 710119, China;
2.Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China;
3.University of Chinese Academy of Sciences, Beijing 100049, China;
4.Academy of Opto-electronics, Chinese Academy of Sciences, Beijing 100094, China
Fund Project:Project supported by the National Natural Science Foundation of China (Grand Nos. 61575197, 61307018), the Starting Foundation for Excellent Doctoral Dissertation of Chinese Academy of Sciences, the President Foundation of University of Chinese Academy of Sciences, the Fusion Foundation of Research and Education of Chinese Academy of Sciences, China, the K. C. Wong Education Foundation, China, and the Young Eagles Program of Academy of Opto-Electronics, Chinese Academy of Sciences.Received Date:10 July 2015
Accepted Date:30 September 2015
Published Online:05 January 2016
Abstract:Ptychography is a new kind of lens-less imaging technology. What restricts the technique is the assumption of a multiplicative interaction between the illuminating coherent beam and the specimen, i.e., and the ptychography cannot be applied to samples no thicker than a few tens of micrometers in the case of visible-light imaging at micron-scale resolution. In the present work, we split a sample into axial sections, thereby realize three-dimensional ptychographic imaging of thick samples at the millimeter level in a series of computer simulations and optical experiments. Our simulation results reveal that by using single wavelength we cannot achieve good-quality images of thick samples. Thus it is necessary to introduce more wavelengths for illumination. With increasing the number of wavelengths, the imaging quality of three-dimensional thick samples can be enhanced continually. Then we make further study on the relationship between the imaging quality and the magnitude of wavelength in optical experiments by using two groups of samples with different thickness values. The results demonstrate that our experimental results are highly consistent with simulations. For our concrete configuration in this paper, the best results of imaging and separation may be obtained for the case of tri-wavelength. At the same time we make a reasonable explanation for the phenomenon of fold-over in the experiment. Our results are important and meaningful for the practical utilizing of three-dimensional ptychography of thick samples.
Keywords: thick samples/
three-dimensional ptychography/
iterative engine/
multi-wavelength
