A light emitting device includes a transparent substrate having first and
second surfaces, a semiconductor layer provided on the first surface, a
first light emission layer provided on the semiconductor layer and
emitting first ultraviolet light including a wavelength corresponding to
an energy larger than a forbidden bandwidth of a semiconductor of the
semiconductor layer, a second light emission layer provided between the
first light emission layer and the semiconductor layer, absorbing the
first ultraviolet light emitted from the first light emission layer, and
emitting second ultraviolet light including a wavelength corresponding to
an energy smaller than the forbidden bandwidth of the semiconductor of
the semiconductor layer, and first and second electrodes provided to
apply electric power to the first light emission layer.