Pellet-start process for making transverse anderson localization optical element

A method of making a transverse Anderson localization (TAL) element includes mixing pellets together to make a mixture, the pellets being of two or more distinct materials having respective wave speeds effective to provide Anderson guiding. The mixture is fused to make a preform which has respective pellet-size areas of the distinct materials corresponding to the pellets in the mixture. One or more stretching operations is performed to stretch the preform into the TAL element.