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

Area of Science:

• Optical imaging
• Detector characterization
• Image processing

Background:

• Accurate point-spread function (PSF) determination is crucial for improving image resolution via deconvolution.
• Existing PSF retrieval methods like slanted-edge or Siemens-star have limitations, including poor angular resolution, intricate patterns, or time-consuming procedures.
• Alternative methods using line-pair charts or point sources suffer from long acquisition times due to low flux or pattern rotation.

Purpose of the Study:

• To present a novel single-shot method for retrieving the complete two-dimensional point-spread function (PSF) of a detection system.
• To overcome the limitations of existing PSF retrieval techniques, such as poor angular resolution and lengthy acquisition times.
• To demonstrate the method's applicability and accuracy in characterizing detector systems, including X-ray detectors.

Main Methods:

• A single-shot technique employing a circular aperture and a back-projection approach, analogous to computed tomography.
• Integration of a sub-pixel-resolution approach to enhance the accuracy of PSF determination.
• Utilizing simulations to analyze the method's noise susceptibility and intrinsic accuracy.

Main Results:

• The developed method successfully retrieves the complete two-dimensional PSF in a single shot.
• The technique overcomes the angular resolution limitations and time-consuming nature of traditional methods.
• Simulations confirmed the method's accuracy and robustness against noise.
• Characterization of an X-ray detector assembly revealed detailed system aberrations.

Conclusions:

• The presented single-shot method offers an efficient and accurate way to determine the complete 2D PSF.
• This technique significantly improves upon existing methods for PSF retrieval in imaging systems.
• The method's versatility allows its application to detector systems across the electromagnetic spectrum, broadening its utility in the imaging community.