Patent ID: 7642714

Claim:
An electroluminescent device comprising a substrate and, adjacent to said substrate, a laminated body composed of an anode electrode directly on said substrate, an electroluminescent layer directly on said anode electrode, a cathode electrode directly on said electroluminescent layer, and 2n+1 transparent dielectric layers directly on said cathode electrode so that the 2n+1 transparent dielectric layers are located on an opposite side of said substrate, where n is an integer value greater than or equal to 3, which transparent dielectric layers alternately have a high refractive index with a refractive index greater than 1.7 and a low refractive index with a refractive index less than or equal to 1.7, and the transparent dielectric layer bordering on the cathode electrode has a high refractive index of n>1.7, whereby reflection of light emitted by the electroluminescent layer at the cathode electrode is reduced by the transparent dielectric layer and transmission of light through the cathode electrode is increased; wherein the 2n+1 transparent dielectric layers comprise seven layers including four layers having the high refractive index and three layers having the low refractive index to generate light having three transmission peaks that lie in wavelength ranges of red, green and blue colors, and wherein the four layers have an increasing layer thickness starting from a first layer bordering on the cathode electrode.