Abstract: The invention relates to a flat-panel display device (1) which is illuminated by a plate-shaped waveguide (7) which is irradiated by a radiation source (15) at one end face (25). The radiation source (15) is arranged in a reflective lighthousing (13), a first part (17) of which is an integral part of a support (3) and a second part (19) is detachable so that the radiation source (15) can be replaced with recesses in the lighthousing, so that the radiation source (15) is space apart from the reflector (29) and at a distance d from the waveguide (7). FIG. 1.