An X-ray detector array comprising: a scintillator pack comprising: an array of scintillator pixels, wherein the scintillator pixels each have a top surface, a bottom surface and side surfaces and wherein the scintillator pixels are arranged such that side surfaces of neighboring scintillator pixels face each other; and an X-ray absorbing layer comprising an electrically insulating matrix material, wherein particles of an electrically insulating highly X-ray absorbing material are integrated into the matrix material, wherein the particles include elements having an atomic number greater than 50, wherein the X-ray absorbing layer is arranged at the bottom surface of scintillator pixels, and an array of scintillation radiation detectors, each of the scintillation radiation detectors being arranged adjacent to an associated scintillator pixel of the scintillator pack for detecting scintillation radiation generated in the scintillator pixel, and an electronic circuit electrically connected to the array of scintillation radiation detectors, characterised in that the X-ray absorbing layer of the scintillator pack is arranged between the array of scintillator pixels of the scintillator pack and the electronic circuit; and wherein a scintillation radiation detecting surface of each one of the scintillation radiation detectors is arranged along a side surface of an associated scintillator pixel, wherein the X-ray absorbing layer covers at least 80% of the bottom surface of each of the scintillator pixels. a scintillator pack comprising: an array of scintillator pixels, wherein the scintillator pixels each have a top surface, a bottom surface and side surfaces and wherein the scintillator pixels are arranged such that side surfaces of neighboring scintillator pixels face each other; and an X-ray absorbing layer comprising an electrically insulating matrix material, an array of scintillator pixels, wherein the scintillator pixels each have a top surface, a bottom surface and side surfaces and wherein the scintillator pixels are arranged such that side surfaces of neighboring scintillator pixels face each other; and an X-ray absorbing layer comprising an electrically insulating matrix material, wherein particles of an electrically insulating highly X-ray absorbing material are integrated into the matrix material, wherein the particles include elements having an atomic number greater than 50, wherein the X-ray absorbing layer is arranged at the bottom surface of scintillator pixels, and an array of scintillation radiation detectors, each of the scintillation radiation detectors being arranged adjacent to an associated scintillator pixel of the scintillator pack for detecting scintillation radiation generated in the scintillator pixel, and an electronic circuit electrically connected to the array of scintillation radiation detectors, characterised in that the X-ray absorbing layer of the scintillator pack is arranged between the array of scintillator pixels of the scintillator pack and the electronic circuit; and wherein a scintillation radiation detecting surface of each one of the scintillation radiation detectors is arranged along a side surface of an associated scintillator pixel, wherein the X-ray absorbing layer covers at least 80% of the bottom surface of each of the scintillator pixels.