Confocal Bragg ptychography for bulk specimens: a numerical demonstration.

摘要: We report on a new X-ray imaging method, which generalizes Bragg ptychography to 3D mapping of embedded crystalline volumes within thick specimens. The sample is probed by pencil beam. diffracted beam magnified an objective and passes through slit in the image plane be monitored 2D detector far-field plane. dimensions incoming opening define confocal volume. Scanning with respect this probe volume, iterative oversampling routine used reconstruct shape projected displacement field extended internal volumes. This takes into account pupil function known aberrations lens. demonstrate method numerical study 3.5 µm grain comprising wall edge dislocations. With volume ∼0.12 3 compound refractive lens aperture 0.49×10 −3 as objective, dislocations are fully resolved sensitivity ∼10 pm. spatial resolution 26×27×123 nm (rms), poor along optical axis being limited size. four times larger aperture, becomes 16×8×123 (rms). found not critical.