Described herein is a system and method for tuning light scatter in an optically functional porous layer of an LED. The layer comprises a non-light absorbing material structure having a plurality of sub-micron pores and a polymer matrix. The non-light absorbing material forms either a plurality of micron-sized porous particles dispersed throughout the layer or a mesh slab, wherein a plurality of sub-micron pores is located within each micron-sized porous particle or forms an interconnected network of sub-micron pores within the mesh slab, respectively. A polymer matrix, such as a high refractive index silicone fills the plurality of sub-micron pores creating an interface between the materials. Refractive index differences between the materials allow for light scatter to occur at the interface of the materials. Light scatter can also be decreased as a function of temperature, creating a system for tuning light scatter in both an off state and on state of an LED.