A multifunctional optical film for enhancing light extraction from a self-emissive light source having a light output surface, comprising: a flexible substrate (114, 122, 189, 260, 261) comprising a substantially optically transmissive material; a structured layer (110, 126, 190) of extraction elements (255, 257) having a first index of refraction on the flexible substrate (114, 122, 189, 260, 261), wherein the extraction elements (255, 257) are not contained within a volume distribution, wherein a substantial portion of the extraction elements (255, 257) are in optical communication with a light emitting region of the self-emissive light source when the optical film is located against the self-emissive light source, and wherein the extraction elements (255, 257) having the first index of refraction comprise first nanoparticles of a first size and second nanoparticles of a second size different from the first size, wherein the first size of the first nanoparticles is a diameter in the range of 60 nm to 10 microns, and the second size of the second nanoparticles is a diameter in the range of 3 nm to 50 nm; and a backfill layer (108, 128, 192, 254, 256) comprising a material having a second index of refraction different from the first index of refraction, wherein the backfill layer (108, 128, 192, 254, 256) forms a planarizing layer over the extraction elements (255, 257) to present an essentially smooth surface to come into contact with the self-emissive light source, wherein a mismatch between the first index of refraction and the second index of refraction is greater than, or equal to 0.3, wherein the structured layer (110, 126, 190) and backfill layer (108, 128, 192, 254, 256) are arranged to be in sufficient proximity to the light output surface in order to at least partially effect extraction of light from that surface when the optical film is located against the self-emissive light source. a flexible substrate (114, 122, 189, 260, 261) comprising a substantially optically transmissive material; a structured layer (110, 126, 190) of extraction elements (255, 257) having a first index of refraction on the flexible substrate (114, 122, 189, 260, 261), wherein the extraction elements (255, 257) are not contained within a volume distribution, wherein a substantial portion of the extraction elements (255, 257) are in optical communication with a light emitting region of the self-emissive light source when the optical film is located against the self-emissive light source, and wherein the extraction elements (255, 257) having the first index of refraction comprise first nanoparticles of a first size and second nanoparticles of a second size different from the first size, wherein the first size of the first nanoparticles is a diameter in the range of 60 nm to 10 microns, and the second size of the second nanoparticles is a diameter in the range of 3 nm to 50 nm; and a backfill layer (108, 128, 192, 254, 256) comprising a material having a second index of refraction different from the first index of refraction, wherein the backfill layer (108, 128, 192, 254, 256) forms a planarizing layer over the extraction elements (255, 257) to present an essentially smooth surface to come into contact with the self-emissive light source, wherein a mismatch between the first index of refraction and the second index of refraction is greater than, or equal to 0.3, wherein the structured layer (110, 126, 190) and backfill layer (108, 128, 192, 254, 256) are arranged to be in sufficient proximity to the light output surface in order to at least partially effect extraction of light from that surface when the optical film is located against the self-emissive light source.