Collimation technology research based on French Test Object

The flash X-ray radiography of the French Test Object (FTO) was studied and a 3-grade collimating system was designed to reduce the generation of scattered background. Except for the traditional 2-grade collimating system, we adopted a third collimator to further control the scattered background. Monte-Carlo simulations suggest that the 3-grade collimating system can effectively control the influence of scattering. The direct-exposure scattered-exposure ratio along each border between different materials can be greatly improved in the accepting plane.