Many LED light sources have a problem to create uniform diffused light, resulting in brightness concentrations – so-called "hot spots" – on backlit surfaces. Light-diffusing (LD) masterbatches from Tosaf Color Service effectively prevent this undesirable phenomenon. In extensive laboratory trials, the micro-fillers it contains were optimized with regard to material, refractive index, transparency, geometry and dimensions. As a result, only very small amounts of masterbatch – namely 1-2 % – are needed to effectively scatter the light in originally transparent material, predominantly polymethylmethacrylate (PMMA) and polycarbonate (PC). At the same time, the light transmission and mechanical properties of the base material are largely retained. In addition to color-neutral grades, combinations with specific colorings and other functional properties such as UV stabilizers are available.