Display unit, display module, and electronic device

1. A display unit comprising:

a light-receiving device comprising:

a first pixel electrode;

an active layer over the first pixel electrode; and

a common electrode over the active layer;

a light-emitting device comprising:

a second pixel electrode;

a light-emitting layer over the second pixel electrode;

an electron-transport layer over the light-emitting layer; and

the common electrode over the electron-transport layer;

a light-blocking layer over the common electrode;

a resin layer over the light-blocking layer; and

a substrate over the resin layer,

wherein a first part of the light-blocking layer and a part of the resin layer overlap each other,

wherein a second part of the light-blocking layer and the resin layer do not overlap each other,

wherein a shortest distance between the common electrode and the first part of the light-blocking layer is smaller than a shortest distance between the common electrode and the second part of the light-blocking layer,

wherein the electron-transport layer comprises a first region and a second region,

wherein each of the first region and the second region comprises an electron-transport material and a first substance,

wherein the first region has a different concentration of the first substance from the second region, and

wherein the first substance is one of a metal, a metallic salt, a metal oxide and an organometallic complex.

2. The display unit according to claim 1 ,

wherein the first region is positioned between the light-emitting layer and the second region, and

wherein the first region has a higher concentration of the first substance than the second region.

3. The display unit according to claim 1 ,

wherein the electron-transport material has a highest occupied molecular orbital level higher than or equal to −6.0 eV, and

wherein the electron-transport material has an electron mobility higher than or equal to 1×10 −7 cm 2 /Vs and lower than or equal to 5×10 −5 cm 2 /Vs when a square root of electric field strength is 600 (V/cm) 1/2 .

4. The display unit according to claim 1 ,

wherein the light-emitting device further comprises a hole-injection layer,

wherein the hole-injection layer is in contact with one of the second pixel electrode and the common electrode,

wherein the one of the second pixel electrode and the common electrode is an anode,

wherein the hole-injection layer comprises a first compound and a second compound,

wherein the first compound has a property of accepting electrons from the second compound, and

wherein the second compound has a highest occupied molecular orbital level higher than or equal to −5.7 eV and lower than or equal to −5.4 eV.

5. The display unit according to claim 1 , wherein the light-receiving device further comprises the electron-transport layer over the active layer.

6. The display unit according to claim 1 ,

wherein the light-receiving device and the light-emitting device further comprise a common layer,

wherein the common layer is positioned over the first pixel electrode and the second pixel electrode,

wherein a first portion of the common layer and the active layer overlap each other, and

wherein a second portion of the common layer and the light-emitting layer overlap each other.

7. The display unit according to claim 1 , wherein the light-emitting device emits blue light.

8. The display unit according to claim 1 , wherein the light-emitting device is a fluorescent device.

9. The display unit according to claim 1 , wherein the resin layer has an island shape.

10. A display module comprising:

the display unit according to claim 1 ; and

one of a connector and an integrated circuit.

11. An electronic device comprising:

the display module according to claim 10 ; and

at least one of an antenna, a battery, a housing, a camera, a speaker, a microphone and an operation button.