Super-resolution SAXS based on PSF engineering and sub-pixel detector translations

Abstract: Small-angle X-ray scattering (SAXS) technique enables convenient nanoscopic characterization for various systems and conditions. Nonetheless, lab-based SAXS systems intrinsically suffer from insufficient x-ray flux and limited angular resolution. Here, we develop a two-step reconstruction methodology to enhance the angular resolution for given experimental conditions. Using minute hardware additions, we show that translating the x-ray detector in subpixel steps and modifying the incoming beam shape results in a set of 2D scattering images which is sufficient for super-resolution SAXS reconstruction. The technique is verified experimentally to show above 25\% increase in resolution. Such advantages have a direct impact on the ability to resolve faster and finer nanoscopic structures and can be implemented in most existing SAXS apparatuses.