Spatial Resolution Analysis of Laboratory-Based X-ray Imaging System : Evaluation using pinhole and edge method

This study evaluates the spatial resolution of a laboratory-based Xray imaging system using two established methods: edge analysis and pinhole imaging. The edge method involves extraction the Edge Spread Function (ESF), computing the Line Spread Function (LSF), and deriving the Modulation Transfer Function (MTF) to assess detector-limited performance. The pinhole method used a small aperture to approximate a point source, from which the Point Spread Function (PSF) is obtained and modelled using a twodimensional Gaussian fit.The results from the edge method showed high consistency, with a MTF50 of approximately 0,755 lp/mm and a Full Width at Half Maximum (FWHM) of around 0,54 mm. These values are in good agreement with the detector manufacturer’s specifications. The pinhole method yielded significantly broader PSF, with a much lower MTF50 of approximately 0,0003 lp/mm, reflecting the full system blur including geometric and source contributions. The study concludes that both methods offer complementary perspectives: the edge method accurately measures the detectors resolution, while the pinhole method provides insight into the total system performance. The results contribute to quality assurance practices and support future system optimization.