TY - CONF A1 - Schumacher, David A1 - Zscherpel, Uwe A1 - Ewert, Uwe A1 - Ullberg, Ch. A1 - Weber, N. A1 - Pantsar, T. A1 - Perez-Fuster, K. T1 - Properties and application areas of photon counting and energy resolving digital detector arrays N2 - Since a few years the direct detection of X-ray photons into electrical signals is allowed by usage of highly absorbing photo conducting materials (e.g. CdTe) as detection layer of an underlying CMOS semiconductor X-ray detector. NDT energies up to 400 keV are today also possible. The image sharpness and absorption efficiency is improved by the replacement of the unsharp scintillation layer (as used at indirect detectors) with a photo conducting layer of much higher thickness and a high voltage across it. If the read-out speed is high enough (ca. 50 – 100 ns dead time) single X-ray photons can be counted and their energy measured. Read-out noise and dark image correction can be avoided. By definition of energy thresholds selected energy ranges of the X-ray spectrum can be detected or also suppressed. This allows material discrimination by dual-energy technique or the reduction of image contributions from scattered radiation, which results in an enhanced contrast sensitivity. To use these advantages in an effective way, a special calibration procedure has to be developed, which considers also time dependent processes in the detection layer. This contribution presents some of these new properties of direct converting DDAs in comparison to the conventional indirect converting detectors for fiber composites and thick walled steel pipes (up to 35 mm wall thickness). Possible new application areas of NDT will be discussed for material discrimination especially within fiber reinforced composites (e.g. CFRC und GFRC). T2 - Digital Industrial Radiology and Computed Tomography CY - Ghent, Belgium DA - 22.06.2015 KW - Dual-energy KW - Photon counting KW - Multi-energy KW - Radiographic Testing (RT) KW - Direct detection PY - 2015 UR - http://www.ndt.net/events/DIR2015/app/content/Slides/92_Zscherpel.pdf N1 - Geburtsname von Schumacher, David: Walter, D. - Birth name of Schumacher, David: Walter, D. AN - OPUS4-36576 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -