A diode array includes a substrate and a plurality of light emitting diodes disposed on the substrate and arranged in an array. Each of the light emitting diodes includes a stack of functional layers includes a first semiconductor layer, a second semiconductor layer, and a light emitting layer located between the first semiconductor layer and the second semiconductor layer. At least one of the light emitting diodes includes a first current limiting region covering at least a portion of the first semiconductor layer, the light emitting layer or the second semiconductor layer; a first electrode electrically connected to the first semiconductor layer; and a second electrode electrically connected to the second semiconductor layer, wherein the first electrode and the second electrode are disposed at the same side of the first semiconductor layer.