X-Ray Near-Field Ptychography for Optically Thick Specimens

High-resolution x-ray imaging in applications ranging from biomedical engineering to paleontology can benefit from inline holography: reconstructing a complex-valued image from x-rays diffracted by a sample. This approach is problematic in strongly absorbing and refracting samples, and when strong illumination inhomogeneities are present. The authors demonstrate, by simultaneously tracking both the complex-valued illumination and transmission functions (so-called ptychographic phase retrieval), that accurate quantitative images of even a highly absorbing uranium-molybdenum sample can be obtained.