In an active matrix electroluminescent display device a storage capacitor (24) is provided in each pixel for storing a voltage to be used for addressing a drive transistor (22) which controls the illumination of the electroluminescent display element (20). A discharge photosensitive element (34) is provided for discharging the charge storage capacitor in dependence on the display element's light output. A further photosensitive element (40) is provided so as to cancel photocurrents produced in the discharge photosensitive element (34) as a result of light input to the discharge photosensitive element other than from the pixel's display element (20), the further photosensitive element being shielded (44) from light emitted by the display element while being exposed to light from other directions. Irregularities in the display output due to the effects of the unwanted light inputs to the discharge photosensitive elements are then avoided.