Print Email Facebook Twitter Automatic Differentiation based Multi-Mode Ptychography Title Automatic Differentiation based Multi-Mode Ptychography: A flexible and highly efficient lensless imaging algorithm Author Wang, Yabin (TU Delft Mechanical, Maritime and Materials Engineering; TU Delft Precision and Microsystems Engineering) Contributor Coene, W.M.J.M. (mentor) Westerveld, W.J. (graduation committee) Shao, Y. (graduation committee) Degree granting institution Delft University of Technology Programme Mechanical Engineering | Precision and Microsystems Engineering Date 2022-08-12 Abstract The scientific community recognizes the critical role played by ptychography in nanoscale imaging. Compared with the conventional imaging, which has high requirements on the manufacturing of optical elements, ptychography, as a computational imaging technique, uses a set of measured intensities of the diffraction patterns to reconstruct the image of the object and hence no imaging system is needed. This technique is especially useful in the short wavelength, e.g. EUV, regime, where manufacturing high quality optical elements such as mirrors is extremely expensive. Most of the present ptychographic algorithms require the illumination of the object to be both spatially and temporally coherent so that the diffraction pattern can be interpreted as the intensity of the Fourier transform of the field exiting the object. However, the coherence of the sources that produce the EUV radiation often cannot be guaranteed. Therefore, it is crucial to extend the ptychography method to consider partial coherence effects. This requires the use of a flexible propagator which depends on the wavelength to deal with the temporal partial coherence and a modal representation for the spatially partially coherent field. Also, the ambiguity of the reconstructed modes of the probe will be solved by an orthogonalization approach, which could enhance the reproducibility of the results. These methods will be implemented on an existing ptychography platform based on automatic-differentiation and will be validated using both simulation data and experimental data. Subject computational imagingPtychographyAutomatic Differentiation To reference this document use: http://resolver.tudelft.nl/uuid:20cc4498-2177-4112-b9d7-e9e2600c625e Part of collection Student theses Document type master thesis Rights © 2022 Yabin Wang Files PDF master_thesis_Yabin_Wang_2_.pdf 41.49 MB Close viewer /islandora/object/uuid:20cc4498-2177-4112-b9d7-e9e2600c625e/datastream/OBJ/view