Patent ID: 8362459
Filing Date: 2013-01-29
Classification: F21K,G02B,H01L

Abstract:
1. A light emitting device comprising: a substrate; a light-emitting structure layer on the substrate, the light-emitting structure layer including a first conductive type semiconductor layer, a second conductive type semiconductor layer, and an active layer between the first and second conductive type semiconductor layers; and a light-transmitting electrode layer on the second conductive type semiconductor layer, wherein the second conductive type semiconductor layer has a thickness satisfying Equation (1): where Φ1 is a phase change that is generated when light of a vertical direction passes through the second conductive type semiconductor layer, Φ2 is a phase change that is generated when the light is reflected by the light-transmitting electrode layer, and N is a natural number, wherein Φ1 is expressed as Equation (2): where n 2 is a refractive index of the second conductive type semiconductor layer, λ is a wavelength of light emitted from the active layer, and d is the thickness of the second conductive type semiconductor layer, wherein the active layer has a thickness equal to or less than λ/n wherein all layers between the active layer and the substrate are formed in a nitride-based semiconductor.