US-12622138-B2 - Display device

US12622138B2US 12622138 B2US12622138 B2US 12622138B2US-12622138-B2

Abstract

A display device includes a pixel circuit on a substrate and including a transistor, a first pixel electrode on the pixel circuit and electrically connected to the pixel circuit, a bank on the first pixel electrode and including first, second, third, and fourth open parts, a first contact electrode on the bank and the first and second open parts and in contact with the first pixel electrode through the first open part, a second pixel electrode overlapping the second and third open parts, the second pixel electrode and the first pixel electrode formed as a same layer, a second contact electrode on the bank and the third and fourth open parts and in contact with the second pixel electrode through the third open part, and a common pixel electrode overlapping the fourth open part, the common pixel electrode and the second pixel electrode formed as a same layer.

Inventors

Dong Hee Shin
Sang Yong NO
Sun Kwun Son

Assignees

SAMSUNG DISPLAY CO., LTD.

Dates

Publication Date: 20260505
Application Date: 20230816
Priority Date: 20221011

Claims (20)

1 . A display device comprising: a pixel circuit disposed on a substrate and including at least one transistor; a first pixel electrode disposed on the pixel circuit and electrically connected to the pixel circuit; a bank disposed on the first pixel electrode and including first, second, third and fourth open parts; a first contact electrode disposed on the bank and the first and second open parts, the first contact electrode being in contact with the first pixel electrode through the first open part; a second pixel electrode overlapping the second and third open parts, the second pixel electrode and the first pixel electrode formed as a same layer; a second contact electrode disposed on the bank and the third and fourth open parts, the second contact electrode being in contact with the second pixel electrode through the third open part; and a common pixel electrode overlapping the fourth open part, the common pixel electrode and the second pixel electrode formed as a same layer.
2 . The display device of claim 1 , further comprising: a first light emitting element comprising: a first electrode corresponding to the first contact electrode, and a second electrode corresponding to the second pixel electrode; and a second light emitting element comprising: a first electrode corresponding to the second contact electrode, and a second electrode corresponding to the common pixel electrode.
3 . The display device of claim 2 , wherein the first light emitting element further comprises: an electron transport layer disposed on the second pixel electrode; a light emitting layer disposed on the electron transport layer; and a hole transport layer disposed between the light emitting layer and the first contact electrode.
4 . The display device of claim 2 , wherein the second light emitting element further comprises: an electron transport layer disposed on the common pixel electrode; a light emitting layer disposed on the electron transport layer; and a hole transport layer disposed between the light emitting layer and the second contact electrode.
5 . The display device of claim 2 , further comprising a separation part disposed on the bank and separating the first and second contact electrodes from each other.
6 . The display device of claim 1 , further comprising: a first voltage line supplying a high potential voltage; a data line supplying a data voltage; and an initialization voltage line supplying an initialization voltage, wherein the pixel circuit comprises: a first transistor electrically connecting the first voltage line and the first pixel electrode to each other based on a voltage of a first node; a second transistor electrically connecting the data line and a gate electrode of the first transistor to each other based on a first gate signal; and a third transistor electrically connecting the initialization voltage line and the first pixel electrode to each other based on a second gate signal different from the first gate signal.
7 . The display device of claim 6 , further comprising: a vertical voltage line supplying a low potential voltage, wherein the common pixel electrode is electrically connected to the vertical voltage line.
8 . A display device comprising: a pixel circuit disposed on a substrate and including at least one transistor; a first pixel electrode disposed on the pixel circuit and electrically connected to the pixel circuit; a bank disposed on the first pixel electrode and including first, second, and third open parts and a power open part; a contact electrode disposed on the bank and the first and second open parts; a second pixel electrode overlapping the second and third open parts and being in contact with the contact electrode through the second open part, the second pixel electrode and the first pixel electrode formed as a same layer; a common cathode electrode disposed on the bank, the third open part, and the power open part; and a common pixel electrode overlapping the power open part and being in contact with the common cathode electrode through the power open part, the common pixel electrode and the second pixel electrode formed as a same layer.
9 . The display device of claim 8 , further comprising: a first light emitting element comprising: a first electrode corresponding to the first pixel electrode, and a second electrode corresponding to the contact electrode; and a second light emitting element comprising: a first electrode corresponding to the second pixel electrode, and a second electrode corresponding to the common cathode electrode.
10 . The display device of claim 9 , wherein the first light emitting element further comprises: a hole transport layer disposed on the first pixel electrode; a light emitting layer disposed on the hole transport layer; and an electron transport layer disposed between the light emitting layer and the contact electrode.
11 . The display device of claim 9 , wherein the second light emitting element further comprises: a hole transport layer disposed on the second pixel electrode; a light emitting layer disposed on the hole transport layer; and an electron transport layer disposed between the light emitting layer and the common cathode electrode.
12 . The display device of claim 9 , further comprising a separation part disposed on the bank and separating the contact electrode and the common cathode electrode from each other.
13 . The display device of claim 8 , further comprising: a vertical voltage line supplying a low potential voltage, wherein the common pixel electrode is electrically connected to the vertical voltage line.
14 . A display device comprising: a pixel circuit disposed on a substrate and including at least one transistor; a driving voltage line disposed on the pixel circuit and supplying a high potential voltage; a bank disposed on the driving voltage line and including first, second, third, and fourth open parts; a first contact electrode disposed on the bank and the first and second open parts, the first contact electrode being in contact with the driving voltage line through the first open part; a first pixel electrode overlapping the second and third open parts, the first pixel electrode and the driving voltage line formed as a same layer; a second contact electrode disposed on the bank and the third and fourth open parts, the second contact electrode being in contact with the first pixel electrode through the third open part; and a second pixel electrode overlapping the fourth open part, the second pixel electrode and the first pixel electrode formed as a same layer.
15 . The display device of claim 14 , further comprising: a first light emitting element comprising: a first electrode corresponding to the first contact electrode, and a second electrode corresponding to the first pixel electrode; and a second light emitting element comprising: a first electrode corresponding to the second contact electrode, and a second electrode corresponding to the second pixel electrode.
16 . The display device of claim 15 , wherein the first light emitting element further comprises: an electron transport layer disposed on the first pixel electrode; a light emitting layer disposed on the electron transport layer; and a hole transport layer disposed between the light emitting layer and the first contact electrode.
17 . The display device of claim 15 , wherein the second light emitting element further comprises: an electron transport layer disposed on the second pixel electrode; a light emitting layer disposed on the electron transport layer; and a hole transport layer disposed between the light emitting layer and the second contact electrode.
18 . The display device of claim 15 , further comprising a separation part disposed on the bank and separating the first and second contact electrodes from each other.
19 . The display device of claim 15 , further comprising: a data line supplying a data voltage; an initialization voltage line supplying an initialization voltage; and a low potential line supplying a low potential voltage; wherein the pixel circuit comprises: a first transistor controlling a driving current based on a voltage of a first node; a second transistor electrically connecting the data line and a gate electrode of the first transistor to each other based on a gate signal; a third transistor electrically connecting the initialization voltage line and a source electrode of the first transistor to each other based on the gate signal; a fourth transistor electrically connecting the driving voltage line and a drain electrode of the first transistor to each other based on the gate signal; a fifth transistor electrically connecting the second electrode of the second light emitting element and the drain electrode of the first transistor to each other based on an emission control signal; and a sixth transistor electrically connecting the source electrode of the first transistor and the low potential line to each other based on the emission control signal.
20 . The display device of claim 19 , wherein the second pixel electrode is electrically connected to a drain electrode of the fifth transistor.

Description

CROSS-REFERENCE TO RELATED APPLICATION(S) This application claims priority to and benefits of Korean Patent Application No. 10-2022-0130100 filed on Oct. 11, 2022, and No. 10-2023-0032769 filed on Mar. 13, 2023, under 35 U.S.C. § 119, in the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference. BACKGROUND 1. Technical Field Embodiments relate to a display device. 2. Description of the Related Art As the information society develops, the demand for display devices displaying images has increased and diversified. For example, display devices have been applied to various electronic devices such as smartphones, digital cameras, laptop computers, navigation devices, and smart televisions. The display devices may be flat panel display devices such as liquid crystal display devices, field emission display devices, or organic light emitting display devices. Among such flat panel display devices, a light emitting display device may display an image without a backlight unit providing light to a display panel because each of pixels of the display panel includes light emitting elements emitting light. The light emitting element may be an organic light emitting diode formed of an organic material as a fluorescent material and an inorganic light emitting diode formed of an inorganic material as a fluorescent material. SUMMARY Embodiments provide a display device capable of decreasing power consumption by increasing luminous efficiency and decreasing a magnitude of a driving current. However, embodiments of the disclosure are not limited to those set forth herein. The above and other embodiments will become more apparent to one of ordinary skill in the art to which the disclosure pertains by referencing the detailed description of the disclosure given below. According to an embodiment, a display device may include a pixel circuit disposed on a substrate and including at least one transistor, a first pixel electrode disposed on the pixel circuit and electrically connected to the pixel circuit, a bank disposed on the first pixel electrode and including first, second, third, and fourth open parts, a first contact electrode disposed on the bank and the first and second open parts and in contact with the first pixel electrode through the first open part, a second pixel electrode overlapping the second and third open parts, the second pixel electrode and the first pixel electrode formed as a same layer, a second contact electrode disposed on the bank and the third and fourth open parts and in contact with the second pixel electrode through the third open part, and a common pixel electrode overlapping the fourth open part, the common pixel electrode and the second pixel electrode formed as a same layer. The display device may further include a first light emitting element comprising a first electrode corresponding to the first contact electrode and a second electrode corresponding to the second pixel electrode, and a second light emitting element comprising a first electrode corresponding to the second contact electrode and a second electrode corresponding to the common pixel electrode. The first light emitting element may further include an electron transport layer disposed on the second pixel electrode, a light emitting layer disposed on the electron transport layer, and a hole transport layer disposed between the light emitting layer and the first contact electrode. The second light emitting element may further include an electron transport layer disposed on the common pixel electrode, a light emitting layer disposed on the electron transport layer, and a hole transport layer disposed between the light emitting layer and the second contact electrode. The display device may further include a separation part disposed on the bank and separating the first and second contact electrodes from each other. The display device may further include a first voltage line supplying a high potential voltage, a data line supplying a data voltage, and an initialization voltage line supplying an initialization voltage. The pixel circuit may include a first transistor electrically connecting the first voltage line and the first pixel electrode to each other based on a voltage of a first node, a second transistor electrically connecting the data line and a gate electrode of the first transistor to each other based on a first gate signal, and a third transistor electrically connecting the initialization voltage line and the first pixel electrode to each other based on a second gate signal different from the first gate signal. The display device may further include a vertical voltage line supplying a low potential voltage. The common pixel electrode may be electrically connected to the vertical voltage line. According to an embodiment, a display device may include a pixel circuit disposed on a substrate and including at least one transistor, a first pixel electrode disposed on the pixel circuit and e