title: Optimal signal-to-noise ratios for soft x-ray lensless imaging.
abstract: We propose and demonstrate a method to gauge and optimize the signal-to-noise ratios (SNRs) in lensless imaging using partially coherent sources. Through spatial filtering we tuned the coherence width of an incoherent soft x-ray undulator source, and we deduce that there exists an optimal spatial filter setting for imaging micrometer-sized objects, while high-resolution imaging is best executed without spatial filtering. Our SNR analysis, given spatial coherence, allows for an estimation of the required exposure time at synchrotron sources and pulse fluence at x-ray laser sources.
authors.affiliation: Department of Applied Physics, Stanford University, Stanford, CA 94305, USA. rrick@stanford.edu
authors.forename: R
authors.initials: R
authors.lastname: Rick
authors.forename: A
authors.initials: A
authors.lastname: Scherz
authors.forename: W F
authors.initials: WF
authors.lastname: Schlotter
authors.forename: D
authors.initials: D
authors.lastname: Zhu
authors.forename: J
authors.initials: J
authors.lastname: Lüning
authors.forename: J
authors.initials: J
authors.lastname: Stöhr