Light-emitting element for efficiently emitting light in different colors

A light-emitting element, comprising:

• a cathode;
• an anode;
• a light-emitting layer formed between the cathode and the anode, and including a plurality of light-emitting regions, respectively, emitting light of different wavelengths;
• and
• an electron-transport layer formed between the cathode and the light-emitting layer, and including a plurality of regions, each of the plurality of regions corresponding to one of the plurality of light-emitting regions,
• the electron-transport layer including a Zn1-XMgXO film (where 0≤X<1), and, of the plurality of regions included in the electron-transport layer, a region, corresponding to the one of the plurality of light-emitting regions that emits light of a shorter wavelength, being higher in a composition ratio X of Mg.

A light-emitting element, comprising:

• a cathode;
• an anode;
• a light-emitting layer formed between the cathode and the anode, and including a plurality of light-emitting region, respectively, emitting light of different wavelengths;
• and
• an electron-transport layer formed between the cathode and the light-emitting layer, and including a plurality of region, each of the plurality of regions corresponding to one of the plurality of light-emitting regions,
• the electron-transport layer including a Zn1-XMgXO film (where 0≤X<1), and, of the plurality of regions included in the electron-transport layer, a region, corresponding to the one of the plurality of light-emitting regions that emits light of a shorter wavelength, being less in a thickness of the Zn1-XMgXO film, wherein
• the light-emitting layer includes a red light emitting region emitting red light, a green light emitting region emitting green light, and a blue light emitting region emitting blue light, and
• of the plurality of regions included in the electron-transport layer, a region, corresponding to the red light emitting region, contains Mg having a composition ratio X of 0 or higher and lower than 0.05, a region, corresponding to the green light emitting region, contains Mg having the composition ratio X of 0.05 or higher and lower than 0.15, and a region, corresponding to the blue light emitting region, contains Mg having the composition ratio X of 0.15 or higher and lower than 0.25.

A light-emitting element, comprising:

• a cathode;
• an anode;
• a light-emitting layer formed between the cathode and the anode, and including a plurality of light-emitting regions, respectively, emitting light of different wavelengths;
• and
• an electron-transport layer formed between the cathode and the light-emitting layer, and including a plurality of regions, each of the plurality of regions corresponding to one of the plurality of light-emitting regions,
• the electron-transport layer including a Zn1-XMgXO film (where 0≤X<1), and, of the plurality of regions included in the electron-transport layer, a region, corresponding to one of the plurality of light-emitting regions that emits light of a shorter wavelength, being less in a thickness of the Zn1-XMgXO film, wherein
• the light-emitting layer includes a red light emitting region emitting red light, a green light emitting region emitting green light, and a blue light emitting region emitting blue light, and
• of the plurality of regions included in the electron-transport layer, a region, corresponding to the red light emitting region, includes the Zn1-XMgXO film having the thickness of 45 nm or more and less than 55 nm, the region a region, corresponding to the green light emitting region-region, includes the Zn1-xMgxO film having the thickness of 35 nm or more and less than 45 nm, and a region, corresponding to the blue light emitting region, includes the Zn1-XMgXO film having the thickness of 25 nm or more and less than 35 nm.