A digital line-camera for energy resolved X-ray photon counting

We describe a digital line-camera that can be used for computed tomography (CT) with energy resolved x-ray photon counting (XPC) capability. The camera is based on pixellated cadmium telluride (CdTe) radiation sensors and application specific integrated circuits (ASICs). Each camera pixel simultaneously counts x-rays in multiple energy bins providing the capability for ¿color¿ x-ray imaging and energy weighted x-ray CT. The camera can be used in pre-clinical x-ray microCT, where energy resolved photon counting is capable of improving contrast in the image and reducing radiation dose to the subject. We began testing the camera using 120-kVp polychromatic x-rays illuminating a phantom consisting of different test materials. Projection data of x-ray intensity transmitted through the phantom at different views were acquired and reconstructed to obtain tomographic images. This article describes the functionality and performance of the camera, and presents preliminary results from x-ray microCT with phantoms.