The present invention relates to a light emitting device comprising several groups of stripe shaped organic light emitting diodes (15, 16, 17) arranged side by side on an optically transparent carrier substrate (4). The organic light emitting diodes (15, 16, 17) comprise a first layer sequence (2) forming a first microcavity. At least one of the organic light emitting diodes (15, 16, 17) of each group comprises a second layer sequence (3) forming a second microcavity between the second electrode layer (5) and the carrier substrate (4). The second microcavity is adapted in thickness of at least one of its layers to increase light out put of the corresponding organic light emitting diode (15, 16, 17). A scatter or diffuser element (14) is arranged in an emission direction of the organic light emitting diodes (15, 16, 17) in front of the carrier substrate (4), to mix the light of said different colors of each group leaving the carrier substrate. The present device allows the emission of white light with a high efficacy.