Abstract: Provided is a light emitting device including a first electrode, a hole transport region on the first electrode, a first light emitting layer on the hole transport region and emitting light of a first wavelength, a second light emitting layer on the hole transport region and emitting light of a second wavelength different from the first wavelength, an electron transport region on the first light emitting layer and the second light emitting layer, and a second electrode on the electron transport region. The second light emitting layer includes a first sub-light emitting layer including a first host having a first hole transporting host and a first electron transporting host and a dopant emitting light of the second wavelength, and a second sub-light emitting layer including a second host and a second hole transporting host, but not including the dopant. The light emitting device provides improved light emitting efficiency.

Abstract: A power supply apparatus is for supplying power to an electric vehicle by a magnetic induction mechanism. The apparatus includes a power supply structure including a multiple number of power supply rail modules connected in a forward road direction, each power supply rail module including at least one power supply line passage elongated in the forward road direction, a power supply core of a lattice structure provided below the power supply line passage, and a concrete structure incorporating the power supply line passage and the power supply core; at least one power supply line accommodated in the power supply line passage in the forward road direction and surrounded by an insulating pipe; and at least one common line provided in the forward road direction and surrounded by an insulating pipe, for supplying power to the power supply apparatus.