Spatial frequency heterodyne imaging in the soft x-ray water window

Abstract

An x-ray imaging modality called Spatial Frequency Heterodyne Imaging (SFHI) is applied in the soft x-ray water window. SFHI permits the computational decomposition of the images acquired with a single-shot exposure into an x-ray absorption image and into two image pairs formed exclusively by x-rays scattered and refracted normally to the orientation of the grid wires. In the experiments, a laser-driven plasma soft x-ray source is used in an imaging setup consisting of a linear arrangement of source, object, a metal grid, and an image detector. Theoretical simulations and experimental results are found to be in a good agreement. SFHI is demonstrated to deliver more detailed sample information than conventional x-ray absorption imaging.