Hagemann, Johannes

[["dc.bibliographiccitation.firstpage","13973"],["dc.bibliographiccitation.issue","13"],["dc.bibliographiccitation.journal","Optics Express"],["dc.bibliographiccitation.lastpage","13989"],["dc.bibliographiccitation.volume","25"],["dc.contributor.author","Hagemann, Johannes"],["dc.contributor.author","Salditt, Tim"],["dc.date.accessioned","2017-10-24T13:00:40Z"],["dc.date.accessioned","2021-10-11T11:35:06Z"],["dc.date.available","2017-10-24T13:00:40Z"],["dc.date.available","2021-10-11T11:35:06Z"],["dc.date.issued","2017"],["dc.description.abstract","We propose a reconstruction scheme for hard x-ray inline holography, a variant of propagation imaging, which is compatible with imaging conditions of partial (spatial) coherence. This is a relevant extension of current full-field phase contrast imaging, which requires full coherence. By the ability to reconstruct the coherent modes of the illumination (probe), as demonstrated here, the requirements of coherence filtering could be relaxed in many experimentally relevant settings. The proposed scheme is built on the mixed-state approach introduced in [Nature494, 68 (2013)], combined with multi-plane detection of extended wavefields [Opt. Commun.199, 65 (2001), Opt. Express22, 16571 (2014)]. Notably, the diversity necessary for the reconstruction is generated by acquiring measurements at different defocus positions of the detector. We show that we can recover the coherent mode structure and occupancy numbers of the partial coherent probe. Practically relevant quantities as the transversal coherence length can be computed from the reconstruction in a straightforward way."],["dc.description.sponsorship","Open-Access-Publikationsfonds 2017"],["dc.identifier.doi","10.1364/OE.25.013973"],["dc.identifier.gro","3142470"],["dc.identifier.pmid","28788984"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/14797"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/90727"],["dc.language","eng"],["dc.language.iso","en"],["dc.notes.intern","Migrated from goescholar"],["dc.notes.status","final"],["dc.relation.issn","1094-4087"],["dc.relation.orgunit","Fakultät für Physik"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.rights","Goescholar"],["dc.rights.access","openAccess"],["dc.rights.uri","https://goedoc.uni-goettingen.de/licenses"],["dc.subject","X-ray imaging; Coherence; Phase retrieval"],["dc.subject.ddc","530"],["dc.subject.gro","x-ray optics"],["dc.subject.gro","x-ray imaging"],["dc.title","Reconstructing mode mixtures in the optical near-field"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","20953"],["dc.bibliographiccitation.issue","18"],["dc.bibliographiccitation.journal","Optics Express"],["dc.bibliographiccitation.lastpage","20968"],["dc.bibliographiccitation.volume","25"],["dc.contributor.author","Hagemann, Johannes"],["dc.contributor.author","Salditt, Tim"],["dc.date.accessioned","2017-11-09T09:39:25Z"],["dc.date.accessioned","2021-10-11T11:31:16Z"],["dc.date.available","2017-11-09T09:39:25Z"],["dc.date.available","2021-10-11T11:31:16Z"],["dc.date.issued","2017"],["dc.description.abstract","We present a phase reconstruction scheme for X-ray near-field holographic imaging based on a separability constraint for probe and object. In order to achieve this, we have devised an algorithm which requires only two measurements - with and without an object in the beam. This scheme is advantageous if the standard flat-field correction fails and a full ptychographic dataset can not be acquired, since either object or probe are dynamic. The scheme is validated by numerical simulations and by a proof-of-concept experiment using highly focused undulator radiation of the beamline ID16a of the European Synchrotron Radiation Facility (ESRF)."],["dc.description.sponsorship","Open-Access-Publikationsfonds 2017"],["dc.identifier.doi","10.1364/OE.25.020953"],["dc.identifier.gro","3142466"],["dc.identifier.pmid","29041506"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/14828"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/90601"],["dc.language","eng"],["dc.language.iso","en"],["dc.notes.intern","Migrated from goescholar"],["dc.notes.status","final"],["dc.relation.issn","1094-4087"],["dc.relation.orgunit","Fakultät für Physik"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.rights","Goescholar"],["dc.rights.access","openAccess"],["dc.rights.uri","https://goedoc.uni-goettingen.de/licenses"],["dc.subject","near-field holography"],["dc.subject.ddc","530"],["dc.subject.gro","x-ray imaging"],["dc.title","Divide and update: towards single-shot object and probe retrieval for near-field holography"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]