Abstract: Embodiments of the invention provide a gallium nitride-based light emitting diode including a transparent electrode, which includes a metal layer and a metal oxide layer. The light emitting diode includes a substrate, an n-type gallium nitride-based semiconductor layer disposed on the substrate, a p-type gallium nitride-based semiconductor layer disposed on the n-type gallium nitride-based semiconductor layer, an active layer interposed between the n-type gallium nitride-based semiconductor layer and the p-type gallium nitride-based semiconductor layer, and a transparent electrode disposed on the p-type gallium nitride-based semiconductor layer. Here, the transparent electrode has a multilayer structure including a first metal layer and a metal oxide layer sequentially stacked one above another, and impedance of the metal oxide layer matches impedance of an external environment at an interface between the metal oxide layer and the external environment.

Abstract: An AC LED lighting apparatus using a voltage edge detector is provided. The AC LED lighting apparatus includes: a rectification unit configured to rectify an AC voltage to output a DC rectified voltage; an LED unit including a first light emitting group and a second light emitting group each including at least one LED; and an LED driving control unit configured to control a serial/parallel connection relationship between the first light emitting group and the second light emitting group by comparing a voltage level of the rectified voltage input from the rectification unit with a reference voltage. The LED driving control unit sets the reference voltage by detecting a slope of the rectified voltage and simultaneously detecting the voltage level of the rectified voltage and the detected slope of the rectified voltage.

Abstract: An optical semiconductor based illuminating apparatus includes a first unit which is disposed on an upper side of a housing and includes protrusions formed on a lower outer side of an optical member surrounding a semiconductor optical device and having an inclined surface inclined upwards from a lower edge of an optical member; and a second unit which accommodates and holds the first unit, so that it can reduce defect rate, improve assembly efficiency, and has excellent durability.