| 摘要 |
The present invention relates to a light emitting device with improved efficiency for optical extraction. The light emitting device includes a light emitting unit and an optical extraction improving unit. The light emitting unit creates and releases the light. The optical extraction improving u nit comprises a first side connected to the light emitting unit and a second side releasing the light externally, and the optical extraction improving unit has a negative refractive index. Moreover, the optical extraction improving unit can define the first side, and it can also define the first material layer which has the refractive index of the first sound as well as the second side. It may also include the second material layer of the refractive index of the second sound which has a different refractive index to the first sound, and the dielectric constant of the first material layer has the same absolute value to the material contacting to the first side, whereas the dielectric constant of the second material layer may be formed to have the same absolute value to the dielectric constant of the material contacting the second side. |
