A display element comprising a single layer of porous material, a discrete drop of liquid and means for connecting a voltage supply to the layer, the layer comprising a plurality of conductive particles covered with a lyophobic and electrically insulating covering, whereby on application of a voltage between the liquid and the layer the drop of liquid moves into the layer, the drop moving back out the layer upon removal of the voltage, the movement of the liquid effecting an optical change when viewed from above the porous layer. |