Spectral Imaging

DECTRIS Hybrid Photon Counting (HPC) X-ray detectors provide direct detection of X-rays with optimized CdTe and CZT solid-state sensors using CMOS readout ASICs. The pixel detectors operate in single-photon counting mode and provide outstanding data quality. They feature high dynamic range, zero dark signal and zero readout noise, thus achieving optimal signal-to-noise ratios at high frame rates. Large-area detectors with flexible geometries can be built using the modular system concept.

Energy-resolving photon-counting HPC detectors can discriminate several different energy levels in the incoming X-ray beam. This is called spectral X-ray imaging and is illustrated in the figure below. In addition to the noise-free detection, spectral X-ray imaging will further reduce the required dose. Detectors featuring energy discrimination will enable new, highly versatile imaging possibilities with significantly less complex instrumentation compared to current state-of-the-art technologies, such as dual energy, kVp switching and dual-layer technology, resolving only two different energy bands of the polychromatic spectrum. Our newest technology offers four counters per pixel enabling the simultaneous acquisition of four energy bands.

Spectral X-ray imaging is especially promising for tasks involving the use of contrast agents, for example iodine and gadolinium, which have K-edges in the energy range relevant for CT and fluoroscopy. Dividing the polychromatic spectrum into different energy bins, allows for an optimal energy weighting, resulting in an increased SNR at the same given dose. Tissue differentiation and specificity can be enhanced using appropriately tailored energy bins.