title: A computational framework for ptychographic reconstructions.
abstract: Ptychography is now a well-established X-ray microscopy tool for synchrotron end-stations equipped with a scanning stage and a pixelated detector. Ptychographic phasing algorithms use information from coherent diffraction to deliver quantitative images of the specimen at a resolution higher than the scanning resolution. These algorithms have traditionally been implemented in software on a per-instrument basis in various degrees of user-friendliness and sophistication. Here, we present Ptypy, a ptychography software written with the intention to serve as a framework across the diverse sets of available instruments and usage cases. A distinctive feature of the software is its formalism, which provides a convenient abstraction of the physical model, thus allowing for concise algorithmic implementations and portability across set-up geometries. We give an overview of the supported usage cases, explain the abstraction layer and design principles, and provide a step-by-step guide describing how an algorithm may be realized in a concise and readable manner. The software capabilities are illustrated with reconstructions from visible light and X-ray data.
authors.affiliation: Department of Physics & Institute of Medical Engineering, Technical University of Munich, 85747 Garching, Germany; Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley 94720, CA, USA.
authors.forename: B
authors.identifier: 0000-0002-6009-6281
authors.initials: B
authors.lastname: Enders
authors.affiliation: School of Physics and Astronomy , University of Southampton, Southampton SO17 1BJ , , UK.
authors.forename: P
authors.initials: P
authors.lastname: Thibault
keywords: Python; X-ray; diffraction; microscopy; phase retrieval; ptychography