Single-shot 2D detector point-spread function analysis employing a circular aperture and a back-projection approach

Knowledge of a detection system's point-spread function (PSF) allows improving image resolution by deconvolving this PSF. The slanted-edge or Siemens-star approaches are commonly used to retrieve the PSF. The latter retrieves the PSF with a poor angular resolution and requires an intricate, sometimes expensive test pattern. The former provides the line-spread function only. Rotating this edge, the PSF could be retrieved in a tedious and time-consuming procedure. Other alternatives are line-pair resolution test charts or point-like light sources, e.g., tiny pinholes or fluorescent beads, which suffer from long acquisition times either due to the need for pattern rotation or very low flux. Here, a single-shot method is presented to retrieve the complete two-dimensional PSF by employing a circular aperture and a back-projection approach similar to computed tomography, which overcomes the issues mentioned above. Additionally, the accuracy of the PSF determination is improved by integrating a sub-pixel-resolution approach. Furthermore, simulations are employed to analyze the method's susceptibility to noise and to assess its intrinsic accuracy. Lastly, an X-ray detector assembly is characterized with this method to showcase the detailed insights into the system's aberrations that can be obtained. Since this technique is not restricted to the X-ray regime, it can be applied to characterize detector systems in other regions of the electromagnetic spectrum. This enables the method's widespread use in the imaging community. (c) 2025 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement     «

Knowledge of a detection system's point-spread function (PSF) allows improving image resolution by deconvolving this PSF. The slanted-edge or Siemens-star approaches are commonly used to retrieve the PSF. The latter retrieves the PSF with a poor angular resolution and requires an intricate, sometimes expensive test pattern. The former provides the line-spread function only. Rotating this edge, the PSF could be retrieved in a tedious and time-consuming procedure. Other alternatives are line-pair...     »