A display element comprises a reservoir and a channel connected to the reservoir. The channel extends across an area including a visible area of the display element, and the reservoir is substantially outside the visible area. The display element further comprises at least one electrode and a luminescent fluid in the reservoir and movable, by means of signals applied to the at least one electrode, between a first position and a second position. In the first position, the luminescent fluid is substantially contained in the reservoir outside the visible area and in the second position, the luminescent fluid extends along the channel to occupy the visible area. The luminescent fluid absorbs light in a first color waveband and converts the absorbed light to light in a second color waveband different from the first color waveband.