New developments in analytical calculation of first order scattering for 3D complex objects

The principle of the analytical calculation of first order scattering used in our simulation code named VXI (Virtual X-ray Imaging) is based on a double ray-tracing [1]. The first step consists in realizing a ray-tracing from the X-ray source point to each point of the object (an elementary volume in practice) including attenuation effect in the primary beam. This calculation gives the number of photons and their direction arriving on each voxel. A voxel acts as a secondary source which properties accord to the physics of X-ray scattering (Compton and Rayleigh) [2]. The second step of the ray-tracing is then done from each voxel of the object in the direction of each pixel of the detector, taking into account the attenuation along the scattering path (fig. 1)