The x-ray diagnostic appts. has an x-ray source and a digital detector composed of a pixel matrix. A scatter beam screen is disposed between the radiation source and the detector for suppressing the stray beams scattered from the object under investigation. The periodicity of the screen is proportional to the reciprocal of the aperture of the pixels in the detector matrix . The spatial frequency of the screen is equal to the reciprocal of the aperture of the detector pixels. The frequency is double the Nyquist frequency of the pixels. The screen is fixed to the detector. The pixel aperture is e.g. 150 microns.
