An approach to overcome the resolution-efficiency trade-off in X-ray scintillator imaging

摘要: To address the well-known "resolution–photon efficiency" trade-off, we developed a lens-coupled X-ray tube-based indirect imaging system that incorporated a thick scintillator plate and lens with a large numerical aperture. This configuration provided sufficient photon flux while maintaining a theoretically high spatial resolution, thereby reducing the core challenge of resolving the defocusing issue induced by a thick scintillator and approaching the theoretical resolution limit. Two key techniques were developed: (1) generalized point spread function (PSF) restoration, which extended the single PSF recovery method to geometrically magnified X-ray imaging systems, demonstrating its suitability for large-NA configurations; and (2) truncated PSF correction, which eliminated the imaging artifacts caused by severe fabrication defects in ultrathin scintillators through PSF truncation, followed by resolution restoration using experimentally measured PSFs. The experimental results showed that in the high-frequency range, the power spectral density was improved by up to 8.45 times for an image on a thick scintillator. High image quality and photon efficiency were achieved simultaneously, demonstrating the feasibility of this integrated strategy. These results provide a critical pathway for overcoming the long-standing resolution efficiency dilemma in indirect X-ray imaging using an X-ray tube source or synchrotron radiation facility.