A display panel for a flat panel display includes an array of LCD devices and an array of LED devices that are configured to radiate light in a light path that impinges on the array of LCD devices, to provide backlighting on the array of LCD devices. A solid colloidal dispersion of particles of a first material having a first index of refraction dispersed in a second material having a second index of refraction, such as a solid foam structure, is provided in the light path to reduce spatial non-uniformity of the backlighting.