| 摘要 |
Disclosed are a light emitting device, a light emitting device package, and a lighting system. The light emitting device includes a light emitting structure including a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer on, a light transmissive substrate having a refractive index lower than a refractive index of a compound semiconductor layer, and a mirror structure layer having a structure in which a first mirror layer having a first refractive index and a second mirror layer having a second refractive index different from the first refractive index are alternately stacked on each other. The first mirror layer has a thickness of W·lambda/(4·n1·m), and the second mirror layer has a thickness of W·lambda/(4·n2·m) in which the W represents a weight constant in a range of about 1.05 to about 1.25. |
