X-ray coherent diffraction imaging with an objective lens: Towards three-dimensional mapping of thick polycrystals

We demonstrate an x-ray coherent imaging method that combines high spatial resolution with the ability to map grains within thick polycrystalline specimens. An x-ray objective serves to isolate an embedded grain. Iterative oversampling routines and Fourier synthesis are used to reconstruct the shape and strain field from the far-field intensity pattern. In a demonstration experiment a ∼500-nm Pt grain embedded in a polycrystalline Pt matrix is mapped in three dimensions without compromising the spatial resolution. No information on the pupil function of the lens is required and lens aberrations are not critical.