a surface emitting light emitting device with a semiconducting substrate , a semiconducting mirror stack positioned on the substrate surface , a spacer layer positioned on the mirror stack , an active region positioned on the spacer layer , a second spacer layer positioned on the active region , a second semiconducting mirror stack positioned on the second spacer layer , and a top contact layer positioned in contact with the second semiconducting mirror stack . the active region includes multiple quantum wells each having a different transition wavelength and positioned on the spacer layer with the quantum well possessing the longest transition wavelength located closest to the spacer layer and additional quantum wells of the multiple quantum wells positioned in order of decreasing transition wavelength so that the sum of the emission from all of the quantum wells results in a broad and uniform output emission spectrum .