An image display comprises: a display device having an image output surface at which an image is displayed as a spaced array of pixel elements; an image guide ( 20 ) coupled to the image output surface of the display device and comprising a plurality of light transmission guides ( 80 ) each having an input end and an output end, the input ends of the light transmission guides being arranged relative to one another so that groups of one or more light transmission guides receive light from respective groups of one or more pixel elements; in which, for a cluster comprising at least a subset of the light transmission guides ( 80 ): at the outer periphery of the cluster, the input ends of the light transmission guides are constrained against expansion by a frame formed of a material having thermal expansion properties which are substantially similar to the thermal expansion properties of the image output surface.
