A Novel and Simple X-Ray Dark Field Imaging

A novel and simple X ray optics 'Owl' capable of dark field imaging due to refraction contrast is under development. That comprises a Bragg case asymmetric monochromator 'M' and an analyzer 'A' in a double crystal arrangement. 'A' has thickness of N x L, where N means integer and L the extinction distance in the Laue case or has a thickness that should provide reasonable transmittant X-ray intensity in the Bragg case. The analyzer can only select the refracted light from object towards the forward diffraction direction, while completely suppresses the intensity toward the diffraction direction at the just Bragg position. Their angular width of diffraction was 0.3 μrad at X-ray energy of 35keV. The spatial resolution available is at the order of 5μm or better. This method has a large potential of application to material science, biology and clinical medicine. Pictures shown as demonstration of dark field imaging is a ceramics with hexagonal outer size of 5 mm, containing 91 holes with diameter of 300μm and human auditory ossicles excised