A study on new approaches in coherent x-ray microscopy of biological specimens [Elektronische Ressource] / Klaus Giewekemeyer

Vol. 5he use of coherent x rays for microscopic imaging has seen a rapid and on- Göttingen Series inTgoing development within the past decade, driven by an increasing availabi- X-ray Physics lity of highly brilliant and coherent sources worldwide. Accordingly, novel me-thods have been developed, which replace the microscope‘s objective lens by a numerical reconstruction scheme. The aim of the present work is to study how very recent experimental and algorithmic developments in the field can be imple-mented towards a highly sensitive and fully quantitative microscopy method for imaging of biological cells. To this end, different experimental approaches are studied, based on coherent far-field as well as near-field diffraction. At first, an application of the novel ptychographic imaging method to single biological cells Klaus Giewekemeyeris presented. In particular, it is demonstrated how weakly scattering biological specimens can be imaged with fully quantitative density contrast. Alongside, a A study on new approaches in coherent sueccessful extension of the method towards soft x-ray energies is described.In the second part of the work it is shown how x-ray waveguides can be used x-ray microscopy of biological specimensas a point source for propagation-based microscopy of single cells in the hard x-ray regime.