Initially, the internship will consist of modeling a faithful model of the detector using the GEANT4 library. GEANT4 is a library developed by CERN, capable of simulating the interactions of particles (photon, electron, neutron, etc.) with matter. We will be particularly interested in the production of photons in the visible spectrum by scintillation or by the Cerenkov effect, following the interaction of an X-ray photon. Secondly, the student will be interested in the development of new detectors, complementary to those already existing, including Cerenkov detectors. The optical transport of photons in the visible spectrum created by interaction of X-ray photons with matter will be the subject of an in-depth study.