Beamline 5 of the Synchrotron Ultraviolet Radiation Facility is a diagnostics end-station used to determine the transverse size of the stored electron beam. The electron beam is imaged onto a CCD camera and the size is determined by a computerized image acquisition system. Because of problems with the previous beam imaging system on beamline 10, e.g. the size measurements depended on the stored electron beam current, this new system was developed. Now the synchrotron radiation does not expose the exit window directly, because the light is deflected 90° using a plane copper mirror. Copper is used to absorb as much short wavelength radiation as possible in order to limit the power deposited in the vacuum window.