A light unit including: a light source; and an optical member that transmits and converts light emitted from the light source, wherein the optical member includes: a light guide; a low refractive index layer that is disposed on the light guide and has a lower refractive index than that of the light guide; a first capping layer that is disposed on the low refractive index layer; and a wavelength conversion layer that is disposed on the first capping layer and includes quantum dots, and the light guide includes a transparent metal oxide.