Patent ID: 7994527

Claim:
An optoelectronic device, comprising: (a) a light emitting diode (LED) comprised of an n-type layer having an n-type electrode, an active region, a p-type layer, and n-type ZnO bonded to the p-type layer, wherein the n-type ZnO comprises a first shaped optical element that is shaped as an n-type ZnO cone for extracting light emitted by the active region, a base of the n-type ZnO cone is bonded to the p-type layer, an angle between the base and sidewalls of the n-type ZnO cone is a critical angle, and a p-type electrode is placed on top of the n-type ZnO cone; and (b) a second shaped optical element inverted relative to the n-type ZnO cone and forming an interface with the sidewalls of the n-type ZnO cone, wherein the second shaped optical element's cross-section is a trapezoid, the interface extracts light emitted by the active region into the second shaped optical element because the second shaped optical element on one side of the interface has a refractive index lower than a refractive index of the n-type ZnO cone on the other side of the interface, the critical angle is determined from the refractive index of the second shaped optical element divided by the refractive index of the n-type ZnO cone, and most light entering the n-type ZnO cone from the active region impinges on the interface within the critical angle for refraction into the second shaped optical element, so that the trapezoid and the n-type ZnO cone provide at least a 500% increase in output power.