Simulation Modeling in Digital Radiography with Allowance for Spatial Outlines of Test Objects

Calculation Model of X-Ray Computed Tomography with Density Assessment Function

“…XOY 1.3. Generalized Model of Projection Formation in X-ray Computed Tomography Models of digital radiographic imaging can be used as the basis for the model of projection formation in computed tomography [24][25][26]. An expression for how digital signals (DS) from detectors are connected with the estimate of the projection has the form…”

“…(3) here is the digital signal from the detector with switched off X-ray source (dark signals), and is the digital signal from the detector without a test object. For an X-ray source with energy spectrum , where is the maximum radiation energy, and a radiation-sensitive element (RSE) of thickness operating in integrated recording mode, the analog signals (AS) that correspond to the digital signal are estimated using a formula similar to the expression from [25], (4) where is the factor of conversion of the absorbed radiation energy into the analog signal; is the number of photons hitting the front surface of the radiation-sensitive element without a test object during projection formation;…”

“…It follows from the analysis of expressions ( 3)-( 6) that the performance of the modeling algorithm depends on the complexity of calculating the energy dependence . In [25], the efficiency of replacing the integrals in ( 4) and ( 5) by parametric interpolation dependences, for example, on the mass thickness, was noted. The indicated approach can be easily implemented for a test object for which Let us dwell on test objects of the kind.…”

“…A sinogram is called ideal if the informative parameter is the density ρ. To form a sinogram, we will use an approach similar to the additive algorithm for modeling radiographic images [25].…”

“…The specificity of the test object affects exclusively the process of forming sinograms. The approach in [25] can be used to modify the block for describing the test object sections. This approach is based on expression (11) using information about the shapes, sizes, and materials of fragments of the test object section.…”