To provide an element structure capable of improving luminance that has been taken out without affecting the characteristics of a selfluminous element.
A light-emitting element includes: a luminous layer 102 for emitting light; and a refraction factor composite structure layer 103 arranged on the optical path of light emitted from the luminous layer 102. The refraction factor composite structure layer 103 includes a structure having characteristics [1] to [4] as follows. [1] The internal structure has at least two types of phase having different refraction factors. [2] At least one of the two or more types of phase is formed by a structure unit of size not smaller than 1 nm and not greater than 1/4 of the wavelength of the visible wavelength light area. [3] The average refraction factor is higher than 1 and lower than the refraction factor of the layer other than the layer including the gas phase among a plurality of layers existing between a phosphor and the refraction factor composite structure layer 103. [4] The internal structure in the thickness direction has a plurality of interfaces in contact with the two or more types of phases in a near-field area to which light can come, from viewpoint of energy, from an interface with the other layer in contact with the refraction ration composite structure layer 103.
Yuji Takeuchi
Yoneda Keikei