Phase retrieval by combined Bragg and fresnel X-ray diffraction imaging

Contrast due to Fresnel diffraction is observed on Bragg diffraction images, obtained with a spatially coherent x-ray beam, of ferroelectric domains inside a periodically poled lithium niobate crystal. It originates mainly from the phase shift between the structure factors of the adjacent domains. This allows the direct determination of the relative phase of the pairs of structure factors involved. [S0031-9007(98)07399-2].