X-ray radiation detectors of “scintillator-photodiode” type for security and nondestructive testing

The dual-energy computer tomography compared with its traditional single-energy variant ensures substantially higher contrast sensitivity. The evaluation of the signal ratio from low-energy and high-energy detectors has been carried out using a simplified model of the dual-energy detector array and accounting for the X-ray tube spectrum. We proposed to use of a dual-energy receiving-detecting circuit with a detector pair ZnSe/CsI or ZnSe/CdWO that allows efficient distinction between muscular and bone tissues, which supports our earlier theoretical assumptions that this method could be successfully used for separate detection of materials differing in their effective atomic number Zeff and local density (e.g., calcium contents in bone densitometry), so as can be turn to account for new generation instruments. A possibility of dual energy tomography use for osteoporosis diagnostics was considered. Direct image reconstruction of biological objects has been carried out, demonstrating details of bones with different density. The density of the bone depends on the calcium content, which is not more than 20 % for the narrow part and about 18,5 % in the broad part. This results obtained were in good agreement with the results of the independent chemical analysis.