A device comprising: a first electrode; a second electrode; a first organic photoactive region disposed between the first electrode and the second electrode; and a second organic photoactive region disposed between the first electrode and the second electrode; wherein the first organic photoactive region and the second organic photoactive region have different absorption characteristics; wherein the device includes a reflective layer, and the first organic photoactive region and the second organic photoactive region are disposed on the same side of the reflective layer, wherein the first organic photoactive region is disposed closer to the reflective layer than the second organic photoactive region, wherein the second organic photoactive region is a stronger absorber at longer wavelengths than the first organic photoactive region, wherein each photoactive region (230, 250) further comprises: an organic acceptor material; and an organic donor material in direct contact with the organic acceptor material, and wherein each organic photoactive region (230, 250) includes the same organic acceptor material and organic donor material, and wherein the ratio of the organic acceptor material to the organic donor material in the first organic photoactive region is different from the ratio of the organic acceptor material to the organic donor material in the second organic photoactive region; characterized in that each photoactive region (230, 250) - comprises a first organic layer (232,252) comprising a mixture of the organic acceptor material and the organic donor material, and a second organic layer (231,251) in direct contact with the first organic layer (232,252), wherein the second organic layer (231,251) comprises an unmixed layer of the organic acceptor material of the first organic layer 232,252), or - - consists of a first organic layer (232, 252) comprising a mixture of the organic acceptor material and the organic donor material; the device further comprising a first exciton blocking layer disposed adjacent to and in direct physical contact with the first organic layer of the first organic photoactive region, and a second exciton blocking layer disposed adjacent to and in direct physical contact with the first organic layer of the second organic photoactive region. a first electrode; a second electrode; a first organic photoactive region disposed between the first electrode and the second electrode; and a second organic photoactive region disposed between the first electrode and the second electrode; wherein the first organic photoactive region and the second organic photoactive region have different absorption characteristics; wherein the device includes a reflective layer, and the first organic photoactive region and the second organic photoactive region are disposed on the same side of the reflective layer, wherein the first organic photoactive region is disposed closer to the reflective layer than the second organic photoactive region, wherein the second organic photoactive region is a stronger absorber at longer wavelengths than the first organic photoactive region, wherein each photoactive region (230, 250) further comprises: an organic acceptor material; and an organic donor material in direct contact with the organic acceptor material, and wherein each organic photoactive region (230, 250) includes the same organic acceptor material and organic donor material, and wherein the ratio of the organic acceptor material to the organic donor material in the first organic photoactive region is different from the ratio of the organic acceptor material to the organic donor material in the second organic photoactive region; characterized in that each photoactive region (230, 250) - comprises a first organic layer (232,252) comprising a mixture of the organic acceptor material and the organic donor material, and a second organic layer (231,251) in direct contact with the first organic layer (232,252), wherein the second organic layer (231,251) comprises an unmixed layer of the organic acceptor material of the first organic layer 232,252), or - - consists of a first organic layer (232, 252) comprising a mixture of the organic acceptor material and the organic donor material; an organic acceptor material; and an organic donor material in direct contact with the organic acceptor material, and wherein each organic photoactive region (230, 250) includes the same organic acceptor material and organic donor material, and wherein the ratio of the organic acceptor material to the organic donor material in the first organic photoactive region is different from the ratio of the organic acceptor material to the organic donor material in the second organic photoactive region; the device further comprising a first exciton blocking layer disposed adjacent to and in direct physical contact with the first organic layer of the first organic photoactive region, and a second exciton blocking layer disposed adjacent to and in direct physical contact with the first organic layer of the second organic photoactive region.