Diffractive shear interferometry for extreme ultraviolet high-resolution lensless imaging

We demonstrate a novel imaging approach and associated reconstruction algorithm for far-field coherent di ractive imaging, based on the measurement of a pair of laterally sheared di raction patterns. The di erential phase profile retrieved from such a measurement leads to improved reconstruction accuracy, increased robustness against noise, and faster convergence compared to traditional coherent di ractive imaging methods. We measure laterally sheared di raction patterns using Fourier-transform spectroscopy with two phase-locked pulse pairs from a high-harmonic source. Using this approach, we demonstrate spectrally resolved imaging at extreme ultraviolet wavelengths between 28 and 35 nm.