Display panels and display apparatuses

1 . A display panel comprising a plurality of cathode unit areas, a spacing area disposed outside the plurality of cathode unit areas and adjacent to the plurality of cathode unit areas, wherein each of the plurality of cathode unit areas is provided with at least one pixel area;

wherein the display panel further comprises:

a thin film transistor layer comprising an auxiliary cathode wiring;

a first conductive layer disposed on the thin film transistor layer, wherein the first conductive layer comprises a plurality of connection electrodes disposed surrounding the plurality of cathode unit areas, and one of the plurality of connection electrodes is connected to the auxiliary cathode wiring, and a side wall of the one of the plurality of connection electrodes is in a concave shape to form an undercut opening disposed surrounding one of the plurality of cathode unit areas;

a light-emitting functional layer disposed on a side of the first conductive layer away from the thin film transistor layer and partitioned at the undercut opening; and

a cathode layer disposed on a side of the light-emitting functional layer away from the thin film transistor layer and partitioned at the undercut opening;

wherein the cathode layer comprises a plurality of first cathodes disposed within the plurality of cathode unit areas and a second cathode disposed within the spacing area, the second cathode is disposed between two adjacent ones of the plurality of cathode unit areas, and the one of the plurality of connection electrodes is disposed surrounding one of the plurality of first cathodes and connected to the one of the plurality of first cathodes.

2 . The display panel of claim 1 , wherein the display panel further comprises a pixel definition layer disposed between the first conductive layer and the light-emitting functional layer, and the pixel definition layer comprises a first opening disposed within the pixel area and a second opening disposed corresponding to the one of the plurality of connection electrodes; and

wherein the light-emitting functional layer comprises a light-emitting part disposed in the first opening, at least a part of the one of the plurality of connection electrodes is disposed in the second opening, and the undercut opening is communicated with the second opening; the one of the plurality of first cathodes covers the light-emitting part within one of the plurality of cathode unit areas, extends into the second opening, and is connected to the one of the plurality of connection electrodes.

3 . The display panel of claim 2 , wherein the one of the plurality of connection electrodes is disposed at least within the spacing area, and the second cathode and the plurality of first cathodes are spaced apart.

4 . The display panel of claim 3 , wherein an orthographic projection of the one of the plurality of connection electrodes on the thin film transistor layer is disposed within an orthographic projection of the second opening on the thin film transistor layer, and the undercut opening comprises a first undercut opening disposed on a side of the one of the plurality of connection electrodes close to the one of the plurality of first cathodes and a second undercut opening disposed on a side away from the one of the plurality of first cathodes; the cathode layer further comprises a third cathode disposed on a side of the one of the plurality of connection electrodes away from the thin film transistor layer and at least within the spacing area; and

wherein the one of the plurality of first cathodes and the third cathode are spaced apart at the first undercut opening, and the second cathode and the third cathode are spaced apart at the second undercut opening.

5 . The display panel of claim 3 , wherein an orthographic projection of the one of the plurality of connection electrodes on the thin film transistor layer partially overlaps with an orthographic projection of the second opening on the thin film transistor layer; the undercut opening is disposed on a side of the one of the plurality of connection electrodes close to the one of the plurality of first cathodes, and the one of the plurality of first cathodes and the second cathode are spaced at the undercut opening.

6 . The display panel of claim 2 , wherein the first conductive layer further comprises an anode disposed within the pixel area, and the light-emitting part is disposed in the first opening and on a side of the anode away from the thin film transistor layer.

7 . The display panel of claim 1 , wherein the plurality of cathode unit areas are arranged along a first direction and a second direction, and the first direction intersects with the second direction; the thin film transistor layer comprises a plurality of auxiliary cathode wirings extending along the second direction, and two opposite sides of each of the plurality of connection electrodes along the first direction are connected to two auxiliary cathode wirings, respectively.

8 . The display panel of claim 7 , wherein electric signals transmitted in the plurality of auxiliary cathode wirings are same or different.

9 . The display panel of claim 7 , wherein the thin film transistor layer further comprises a second conductive layer, and the second conductive layer comprises the auxiliary cathode wirings and a plurality of data lines extending along the second direction.

10 . The display panel of claim 1 , wherein the one of the plurality of connection electrodes comprises a first sub-layer and a second sub-layer disposed in stack, the second sub-layer is disposed between the first sub-layer and the thin film transistor layer, and a side wall of the second sub-layer is in a concave shape relative to a side wall of the first sub-layer to form the undercut opening at a side wall of the one of the plurality of connection electrodes.

11 . The display panel of claim 1 , wherein the one of the plurality of connection electrodes comprises a first sub-layer, a second sub-layer, and a third sub-layer disposed in stack,

wherein the second sub-layer is disposed between the first sub-layer and the third sub-layer, the third sub-layer is disposed between the second sub-layer and the thin film transistor layer, and both of a side wall of the second sub-layer and a side wall of the third sub-layer are in a concave shape relative to a side wall of the first sub-layer to form the undercut opening.

12 . The display panel of claim 1 , wherein the first conductive layer further comprises an anode disposed within the pixel area, and the light-emitting part is disposed within the first opening and on a side of the anode away from the thin film transistor layer; and

wherein the one of the plurality of connection electrodes and the anode are arranged in a same layer, and a side wall of the anode is provided with another undercut opening having a same structure as the undercut opening of the one of the plurality of connection electrodes.

13 . The display panel of claim 1 , wherein each of the plurality of cathode unit areas comprises three pixel areas, each of the plurality of connection electrodes is disposed around one of the plurality of cathode unit areas, and each the plurality of first cathodes correspondingly covers the three pixel areas.

14 . The display panel of claim 1 , wherein an orthographic projection of the one of the plurality of connection electrodes on the thin film transistor layer partially overlaps with an orthographic projection of the second opening on the thin film transistor layer, the undercut opening is disposed on a side of the one of the plurality of connection electrodes close to the one of the plurality of first cathodes and communicated with the second opening, and the one of the plurality of first cathodes extends into the undercut opening and is connected to the one of the plurality of connection electrodes.

15 . A display apparatus comprising a display panel, wherein the display panel comprises a plurality of cathode unit areas, a spacing area disposed outside the plurality of cathode unit areas and adjacent to the plurality of cathode unit areas, wherein each of the plurality of cathode unit areas is provided with at least one pixel area;

wherein the display panel further comprises:

a thin film transistor layer comprising an auxiliary cathode wiring;

a first conductive layer disposed on the thin film transistor layer, wherein the first conductive layer comprises a plurality of connection electrodes disposed surrounding the plurality of cathode unit areas, and one of the plurality of connection electrodes is connected to the auxiliary cathode wiring, and a side wall of the one of the plurality of connection electrodes is in a concave shape to form an undercut opening disposed surrounding one of the plurality of cathode unit areas;

a light-emitting functional layer disposed on a side of the first conductive layer away from the thin film transistor layer and partitioned at the undercut opening; and

a cathode layer disposed on a side of the light-emitting functional layer away from the thin film transistor layer and partitioned at the undercut opening;

wherein the cathode layer comprises a plurality of first cathodes disposed within the plurality of cathode unit areas and a second cathode disposed within the spacing area, the second cathode is disposed between two adjacent ones of the plurality of cathode unit areas, and the one of the plurality of connection electrodes is disposed surrounding one of the plurality of first cathodes and connected to the one of the plurality of first cathodes.

16 . The display apparatus of claim 15 , wherein the display panel further comprises a pixel definition layer disposed between the first conductive layer and the light-emitting functional layer, and the pixel definition layer comprises a first opening disposed within the pixel area and a second opening disposed corresponding to the one of the plurality of connection electrodes; and

wherein the light-emitting functional layer comprises a light-emitting part disposed in the first opening, at least a part of the one of the plurality of connection electrodes is disposed in the second opening, and the undercut opening is communicated with the second opening; the one of the plurality of first cathodes covers the light-emitting part within one of the plurality of cathode unit areas, extends into the second opening, and is connected to the one of the plurality of connection electrodes; the one of the plurality of connection electrodes is disposed at least within the spacing area, and the second cathode and the plurality of first cathodes are spaced apart.

17 . The display apparatus of claim 16 , wherein an orthographic projection of the one of the plurality of connection electrodes on the thin film transistor layer is disposed within an orthographic projection of the second opening on the thin film transistor layer, and the undercut opening comprises a first undercut opening disposed on a side of the one of the plurality of connection electrodes close to the one of the plurality of first cathodes and a second undercut opening disposed on a side away from the one of the plurality of first cathodes; the cathode layer further comprises a third cathode disposed on a side of the one of the plurality of connection electrodes away from the thin film transistor layer and at least within the spacing area; and

wherein the one of the plurality of first cathodes and the third cathode are spaced apart at the first undercut opening, and the second cathode and the third cathode are spaced apart at the second undercut opening.

18 . The display apparatus of claim 16 , wherein an orthographic projection of the one of the plurality of connection electrodes on the thin film transistor layer partially overlaps with an orthographic projection of the second opening on the thin film transistor layer; the undercut opening is disposed on a side of the one of the plurality of connection electrodes close to the one of the plurality of first cathodes, and the one of the plurality of first cathodes and the second cathode are spaced at the undercut opening.

19 . The display apparatus of claim 15 , wherein the plurality of cathode unit areas are arranged along a first direction and a second direction, and the first direction intersects with the second direction; the thin film transistor layer comprises a plurality of auxiliary cathode wirings extending along the second direction, and two opposite sides of each of the plurality of connection electrodes along the first direction are connected to two auxiliary cathode wirings, respectively; and

wherein the one of the plurality of connection electrodes comprises a first sub-layer and a second sub-layer disposed in stack, the second sub-layer is disposed between the first sub-layer and the thin film transistor layer, and a side wall of the second sub-layer is in a concave shape relative to a side wall of the first sub-layer to form the undercut opening at a side wall of the one of the plurality of connection electrodes.

20 . A display panel comprising a cathode unit area, a spacing area disposed outside the cathode unit area and adjacent to the cathode unit area, wherein the cathode unit area is provided with at least one pixel area;

wherein the display panel further comprises:

a thin film transistor layer comprising an auxiliary cathode wiring;

a first conductive layer disposed on the thin film transistor layer, wherein the first conductive layer comprises a connection electrode disposed surrounding the cathode unit area and connected to the auxiliary cathode wiring, and a side wall of the connection electrode is in a concave shape to form an undercut opening disposed surrounding the cathode unit area;

a light-emitting functional layer disposed on a side of the first conductive layer away from the thin film transistor layer and partitioned at the undercut opening;

a pixel definition layer disposed between the first conductive layer and the light-emitting functional layer, wherein the pixel definition layer comprises a first opening disposed within the pixel area and a second opening disposed corresponding to the connection electrode; and

a cathode layer disposed on a side of the light-emitting functional layer away from the thin film transistor layer and partitioned at the undercut opening;

wherein the cathode layer comprises a first cathode, a second cathode, and a third cathode; the first cathode is disposed within the cathode unit area, the connection electrode is disposed around the first cathode and is connected to the first cathode; the second cathode is disposed within the spacing area; the third cathode is disposed on a side of the connection electrode away from the thin film transistor layer and at least within the spacing area;

wherein the undercut opening comprises a first undercut opening disposed on a side of the connection electrode close to the first cathode and a second undercut opening disposed on a side away from the first cathode; and

wherein the first cathode and the third cathode are spaced apart at the first undercut opening, and the second cathode and the third cathode are spaced apart at the second undercut opening.