A polymeric composition, comprising: from 90.0 wt.-% to 99.9 wt.-%, based on the weight of the polymeric composition, of a polymeric matrix material which is substantially transparent and has a refractive index n Dm of from 1.35 to 1.65; from 0.05 wt.-% to 5.0 wt.-%, preferably from 0.5 wt.-% to 5.0 wt.-%, more preferably from 1.0 wt.-% to 4.0 wt.-%, based on the weight of the polymeric composition, of a plurality of first scattering particles being polybutylacrylate-based scattering particles which are uniformly dispersed in the polymeric matrix material, wherein the first scattering particles are substantially spherical crosslinked polymeric particles having an average particle size d 1 of from 5.0 μm to 20.0 μm and having a refractive index n D1, wherein the refractive index n D1 is lower than the refractive index n Dm and the absolute difference between the refractive index n D1 and the refractive index n Dm is not lower than 0.04; from 0.05 wt.-% to 5.0 wt.-%, based on the weight of the polymeric composition, of a plurality of second scattering particles chemically different from the first scattering particles which are uniformly dispersed in the polymeric matrix material, wherein the second scattering particles are substantially spherical crosslinked polymeric particles having an average particle size d 2 of from 1.0 μm to 50.0 μm and having a refractive index n D2, wherein the absolute difference between the refractive index n D2 and the refractive index n Dm is from 0.005 to 0.1, wherein the refractive indexes n Dm, n D1, and n D2 are measured at the Na D-line at 589 nm at 23 °C, and the average particle size of the first scattering particles and of the second scattering particles is a volume averaged d 50 value and is measured in accordance with the standard for laser diffraction measurements ISO 13320-1. from 90.0 wt.-% to 99.9 wt.-%, based on the weight of the polymeric composition, of a polymeric matrix material which is substantially transparent and has a refractive index n Dm of from 1.35 to 1.65; from 0.05 wt.-% to 5.0 wt.-%, preferably from 0.5 wt.-% to 5.0 wt.-%, more preferably from 1.0 wt.-% to 4.0 wt.-%, based on the weight of the polymeric composition, of a plurality of first scattering particles being polybutylacrylate-based scattering particles which are uniformly dispersed in the polymeric matrix material, wherein the first scattering particles are substantially spherical crosslinked polymeric particles having an average particle size d 1 of from 5.0 μm to 20.0 μm and having a refractive index n D1, wherein the refractive index n D1 is lower than the refractive index n Dm and the absolute difference between the refractive index n D1 and the refractive index n Dm is not lower than 0.04; from 0.05 wt.-% to 5.0 wt.-%, based on the weight of the polymeric composition, of a plurality of second scattering particles chemically different from the first scattering particles which are uniformly dispersed in the polymeric matrix material, wherein the second scattering particles are substantially spherical crosslinked polymeric particles having an average particle size d 2 of from 1.0 μm to 50.0 μm and having a refractive index n D2, wherein the absolute difference between the refractive index n D2 and the refractive index n Dm is from 0.005 to 0.1, wherein the refractive indexes n Dm, n D1, and n D2 are measured at the Na D-line at 589 nm at 23 °C, and the average particle size of the first scattering particles and of the second scattering particles is a volume averaged d 50 value and is measured in accordance with the standard for laser diffraction measurements ISO 13320-1.