Abstract: A light emitting device may include a light emitting layer such as an organic semiconductor material, one or more feedback structures, and a coupling structure. The one or more feedback structures may cause light emitted by the light emitting layer to be fed back through it along an axis in the plane of the device, thereby promoting the stimulated emission of light in the light emitting layer. The coupling structure couples some fraction of the feedback light out of the device. The coupled light may be emitted along an axis substantially normal to the plane of the device or at predetermined angles. The coupling and feedback structures may have a corrugated structure, a continuous variation of refractive index along an axis in the device plane, a period refractive index, or any combination thereof. The coupling and feedback structures may be separate, share common portion or combined together.