An organic light emitting device is provided. The device has a plurality of regions, each region having an organic emissive layer adapted to emit a different spectrum of light. The regions in combination emit light suitable for illumination purposes. The area of each region may be selected such that the device is more efficient that an otherwise equivalent device having regions of equal size. The regions may have an aspect ratio of at least about four. All parts of any given region may be driven at the same current.