Electroluminescent Element and Lighting Apparatus Comprising the Same

摘要

An electroluminescent element includes a first transparent electrode, a second transparent electrode, a light emitting layer sandwiched between the first transparent electrode and the second transparent electrode, a first transparent member formed on a surface of the first transparent electrode opposite to the light emitting layer, and a second transparent member formed on a surface of the second transparent electrode opposite to the light emitting layer, wherein refractive indices of the first transparent electrode and the second transparent electrode are selected such that as seen from the light emitting layer, a reflectance of an interface between the light emitting layer and the first transparent electrode becomes higher than a reflectance of an interface between the light emitting layer and the second transparent electrode, and wherein a refractive index of the first transparent member is set to be higher than a refractive index of the second transparent member.

主权项

1. An electroluminescent element comprising:
a first transparent electrode; a second transparent electrode; a light emitting layer sandwiched between said first transparent electrode and said second transparent electrode; a first transparent member formed on a surface of said first transparent electrode opposite to said light emitting layer; and a second transparent member formed on a surface of said second transparent electrode opposite to said light emitting layer,
refractive indices of said first transparent electrode and said second transparent electrode being selected such that as seen from said light emitting layer, a reflectance of an interface between said light emitting layer and said first transparent electrode becomes higher than a reflectance of an interface between said light emitting layer and said second transparent electrode,a refractive index of said first transparent member being set to be higher than a refractive index of said second transparent member,each of a thickness of said first transparent electrode and a thickness of said second transparent electrode being not greater than a wavelength of light in said light emitting layer emitted from said light emitting layer,a thickness of said first transparent member being not smaller than a wavelength of light in said first transparent member, anda thickness of said second transparent member being not smaller than a wavelength of light in said second transparent member.