Figure 1. a, b.

Detector design. Panel (a) shows working principles of the conventional and dual layer detectors. While in conventional CT imaging the detector registers photons of a polyenergetic x-ray spectrum irrespective of their energy (left), the dual layer detector in SDCT registers low and high energy photons separately (right). In the upper row, photons of lower energies are registered while the bottom row layer detects high energetic photons. This stacked detector design requires a side locked read out of photodiodes, whereas these components are placed horizontally in conventional detectors. Not true to scale. Panel (b) shows examples of available image reconstructions.