Perovskite computed tomography imager and three-dimensional reconstruction

Indirect scintillator computed tomography (CT) imaging suffers from reduced image contrast and high-dose X-ray exposure due to inevitable light losses and multiple energy conversion steps. Here we report a direct lead-halide perovskite CT imager through low-cost spray-coating processes. Detector arrays with 980 mu m absorber thickness and <10 nm surface roughness yield uniform X-ray response with detection quantum efficiency of 80% and noise-equivalent dose of 153 pGy(air). The perovskite CT imager affords the three-dimensional reconstruction of a tooth under a low effective dose of 5.5 mu Sv, about two orders of magnitude smaller than dental cone-beam CT, and low-contrast detectability by resolving a 5 Hounsfield unit difference within a 5 mm region of interest.