The invention relates to a system (100) for generating and collimating an X-ray beam (104), comprising an X-ray tube insert for generating the X-ray beam, the X-ray tube inert being a vacuum tube a tube housing (102) for containing the X-ray tube insert (101), the tube housing being made of X-ray absorbing material a collimator (103) for collimating the X-ray beam (104) wherein the collimator (103) is arranged in between the X-ray tube insert (101) and the tube housing (102). The invention also relates to a corresponding apparatus for scanning an object of interest with an X-ray beam (104) comprising the system.