Display panel and display device

Abstract

The invention provides a display panel and a display device.The display panel comprises a display area and a non-display area surrounding the display area, the display area comprises a first area and a second area, and the second area surrounds the first area; the first electrode layer is located on one side of the substrate; the at least one transparent film layer is located on the side, away from the substrate, of the first electrode layer in the second area and extends to the non-display area along the second area. By adopting the technical scheme, the transparent film layer is added to play a role in raising the film layer from the edge of the display area to the non-display area, so that the film thickness from the center of the display area to the edge is kept consistent, and the phenomena of edge brightness reduction (different colors) and color halo caused by reduction of the edge thickness of the display area are improved.

Description

Technical Field

[0001] Embodiments of the present invention relate to the field of display technologies, and particularly to a display panel and a display device. Background Art

[0002] With the continuous maturity of the application of display panels in devices such as mobile phones and watches, the application fields of display panels are also constantly expanding. For example, in recent years, the application of display panels in electronic products such as vehicles and laptops has gradually increased. The reliability issue of flexible products is one of the most concerned issues, and there are problems such as a reduction in the edge thickness caused by ink printing in flexible products, resulting in a reduction in the edge brightness and color halo phenomenon of the display screen. Summary of the Invention

[0003] The present invention provides a display panel and a display device. By adding a transparent film layer at the edge of the lower display area to raise the film layer of the display area edge to the film layer of the non-display area, the edge brightness reduction (color difference) and color halo phenomenon caused by the low edge thickness of the display area are improved.

[0004] In a first aspect, an embodiment of the present invention provides a display panel, including a display area and a non-display area surrounding the display area. The display area includes a first area and a second area, and the second area surrounds the first area;

[0005] A substrate;

[0006] A first electrode layer, located on one side of the substrate;

[0007] At least one transparent film layer, located on the side of the first electrode layer in the second area away from the substrate, and extending along the second area to the non-display area.

[0008] In a second aspect, an embodiment of the present invention further provides a display device, which includes the display panel provided in the first aspect.

[0009] The display panel provided by the embodiment of the present invention includes a display area and a non-display area surrounding the display area. The display area includes a first area and a second area, and the second area surrounds the first area; the first electrode layer is located on one side of the substrate; at least one transparent film layer is located on the side of the first electrode layer in the second area away from the substrate, and extends along the second area to the non-display area. By adopting the above technical solution, in the embodiment of the present invention, by adding a transparent film layer to raise the film layer of the display area edge to the film layer of the non-display area, the film thickness from the center to the edge of the display area is kept consistent, thereby improving the edge brightness reduction (color difference) and color halo phenomenon caused by the reduction of the edge thickness of the display area. Description of the Drawings

[0010] Figure 1 is a schematic structural diagram of a display panel provided by the prior art;

[0011] Figure 2 is Figure 1 a schematic cross-sectional view of a display panel along the AA' direction in

[0012] Figure 3 a schematic structural view of a display panel provided by an embodiment of the present invention;

[0013] Figure 4 is Figure 3 a schematic cross-sectional view of a display panel along the BB' direction in

[0014] Figure 5 a schematic structural view of another display panel provided by an embodiment of the present invention;

[0015] Figure 6 is Figure 5 a schematic cross-sectional view of a display panel along the CC' direction in

[0016] Figure 7 is Figure 5 a schematic cross-sectional view of another display panel along the CC' direction in

[0017] Figure 8 is Figure 3 a schematic cross-sectional view of another display panel along the BB' direction in

[0018] Figure 9 a schematic structural view of another display panel provided by an embodiment of the present invention;

[0019] Figure 10 a schematic structural view of a display device provided by an embodiment of the present invention. Detailed implementation manners

[0020] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. In addition, it should be noted that for the convenience of description, only parts related to the present invention are shown in the drawings, rather than all the structures.

[0021] Figure 1 is a schematic structural view of a display panel provided by the prior art, Figure 2 is Figure 1 a schematic cross-sectional view of a display panel along the AA' direction in , referring to Figure 1 and Figure 2, in the prior art, the display panel 100 is a flexible product. Usually, the number of inner film layers in the non-display area A0' is reduced. When using the Chemical Vapor Deposition (CVD) process to prepare the film layer above the display panel 100, the edge height of the inkjet printing layer IJP and the organic film layer on the thin film encapsulation layer 10 decreases near the edge (Border) area of the display area A0, as shown in Figure 3 h shown in, which makes the overall film thickness of the display area A0 inconsistent, and this easily leads to the phenomenon of different colors and color halos at the edge of the display area A0 of this flexible product.

[0022] Among them, the Chemical Vapor Deposition (CVD) method refers to a gas-phase reaction at high temperature. For example, the thermal decomposition of metal halides, organometals, hydrocarbons, etc., hydrogen reduction or the chemical reaction of its mixed gas at high temperature to precipitate inorganic materials such as metals, oxides, and carbides. The inkjet printing layer IJP mainly uses organic materials. These materials are dissolved into "ink" during the inkjet printing process and then printed on the substrate surface. It has a certain fluidity. When the surface height of the substrate it flows through is inconsistent, there is a difference in the film layer thickness.

[0023] And the common solution is to extend the spraying area of the inkjet printing layer IJP and the organic film layer in the display area A0 to the non-display area A0' to try to ensure that the film thickness of the display area A0 is consistent, so as to reduce the display problems caused by the thickness reduction at the edge of the display area A0. However, based on the current product design, due to the requirement of the distance d from the border of the display panel 100 to the display area A0, on the one hand, it cannot be infinitely expanded outward. The expansion itself will also bring the problem of increased reliability risk. On the other hand, the thickness of the inkjet printing layer IJP decreases, the light-emitting angle changes, and the light-emitting intensity also changes. At the same time, due to the change in the thickness of the organic film layer, the equal-thickness interference phenomenon of the upper thin film will also occur, thus generating the edge color halo phenomenon.

[0024] Based on one or more of the above technical problems, an embodiment of the present invention provides a display panel, including a display area and a non-display area surrounding the display area. The display area includes a first area and a second area, and the second area surrounds the first area; a first electrode layer is located on one side of the substrate; at least one transparent film layer is located on the side of the first electrode layer in the second area away from the substrate and extends along the second area to the non-display area.

[0025] By adopting the above technical solution, the embodiment of the present invention pads the film layer from the edge of the display area to the non-display area by adding a transparent film layer, so that the film thickness from the center to the edge of the display area remains consistent, thereby improving the edge brightness reduction (different colors) and color halo phenomenon caused by the reduction of the edge thickness of the display area.

[0026] The above is the core idea of the present invention. Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the protection scope of the present invention.

[0027] Figure 3 It is a schematic structural diagram of a display panel provided by an embodiment of the present invention. Figure 4 is Figure 3 A cross-sectional schematic diagram of a display panel along the BB' direction in, refer to Figures 3 - 4 In this regard, the display panel 200 provided by the embodiment of the present invention includes a display area AA and a non-display area NA surrounding the display area AA. The display area AA includes a first area A1 and a second area A2, and the second area A2 surrounds the first area A1.

[0028] Among them, the display panel 200 can be an organic light-emitting diode display panel (OLED), an active-matrix organic light-emitting diode display panel (AMOLED), etc. The embodiment of the present invention does not limit the specific light-emitting type of the display panel. The display area AA can display images normally, and the non-display area NA at least partially surrounds the display area and is used to set signal traces and protect the display area, etc. The display area AA is divided into a first area A1 and a second area A2 according to the center and the edge. The second area A2 surrounds the first area A1, and the width of the second area A2 can be about 500 μm. In this range area, there are prone to brightness reduction (color difference) and color halo phenomena during display. The present invention designs the film layer structure for this area. Specifically:

[0029] Refer to Figure 4 In this regard, the material of the substrate 20 used in the embodiment of the present invention includes, but is not limited to, rigid materials such as glass or silicon wafers, and can also be flexible materials such as ultra-thin glass, metal foils, or polymer plastic materials. The flexible or rigid substrate 20 can block oxygen and moisture and prevent moisture or impurities from diffusing into the display panel 200 through the substrate 20.

[0030] The first electrode layer 30 is located on one side of the substrate 20. Exemplarily, when the display panel 200 is an OLED display panel, the first electrode layer 30 can be the cathode layer of the OLED light-emitting device, and this layer can be a whole film layer. Its materials include, but are not limited to, transparent conductive materials, such as ITO (indium tin oxide), IZO (indium zinc oxide), ITO / Ag / ITO, etc.

[0031] At least one transparent film layer 40 is located on the side of the first electrode layer 30 away from the substrate 20 within the second region A2, and extends along the second region A2 to the non-display region NA. Specifically, in the present invention, within the range from the second region A2 to the non-display region AA, at least one transparent film layer 40 is added on the side of the first electrode layer 30 away from the substrate 20. By the transparent film layer 40, the thickness of the film layer below the edge of the inkjet printing layer IJP at the boundary of the display region AA is increased, the fluidity of the ink is blocked, the thickness of the film layer within the range from the second region A2 to the connected non-display region NA is stacked and increased, the boundary thickness difference is reduced, and the reduction in the film layer thickness caused by the flow of the upper inkjet printing layer IJP and the organic film layer at the edge of the display region AA is offset, ensuring the film thickness uniformity of the display region AA, thereby improving the display color difference and edge color halo phenomena caused by the decrease in the thickness at the edge of the display region AA.

[0032] It should be noted that referring to Figure 4 , the display panel 200 further includes other functional film layers, such as a driving circuit layer 70, a pixel definition layer (Pixel Definition Layer, PDL), a common layer CMM, inorganic layers CVD1 and CVD2, an inkjet printing layer IJP, a touch layer TP, a packaging layer OC, etc. Among them, the driving circuit layer 70 includes pixel circuits, and the pixel circuits can be circuit structures such as 2T1C, 4T1C, 7T1C, 7T2C, 8T1C, 8T2C, etc. The pixel circuits include multiple thin film transistors (Thin Film Transistor, TFT), storage capacitors (not shown in the figure), and metal wiring and other film layer structures (not shown in the accompanying drawings of the embodiments of the present invention). The display panel 200 further includes multiple light-emitting units (not shown in the figure), and the light-emitting units include OLEDs. The light-emitting units include a second electrode (anode), a light-emitting layer, and a first electrode layer 30. The light-emitting units are located on the side of the driving circuit layer 70 away from the substrate 20, and the pixel circuits are electrically connected to the anodes of the light-emitting units to provide driving voltages for the light-emitting units to drive them to emit light. Among them, the first electrode layer 30 can be the cathode layer of the OLED light-emitting device. The common layer CMM includes, but is not limited to, a hole blocking layer (hole blocking layer, HBL) and / or an electron transportation layer (electron transportation layer, ETL). The multiple film layers work together to achieve the normal display of the display panel, which will not be elaborated here.

[0033] Based on the above embodiments, continue to refer to Figure 3, along the direction from the first region A1 to the second region A2, the width d1 of the second region A2 is less than the width d2 of the first region A1. It should be noted that, based on the difference between the thickness of the inkjet printing layer IJP within the display region AA and the thickness of the inkjet printing layer IJP at the boundary of the display region AA, the design of the transparent film layer 40 usually starts from a position 500 um away from the boundary of the display region AA within the display region AA. In this way, it is possible to avoid the problem that the range of the transparent film layer 40 added inside the second region A2 is too wide, resulting in a significant bulge in the thickness of the film layer at the boundary of the display region, thereby ensuring the consistency of the film thickness of the entire display region.

[0034] Optionally, the width of the second region A2 is less than or equal to 500 μm. With this setting, it is possible to avoid the transparent film layer 40 in the second region A2 from being too wide and causing a bulge at the edge of the display region AA.

[0035] Based on the above embodiments, continue to refer to Figure 4 , the transparent film layer 40 includes an inorganic conductive layer. Specifically, the transparent film layer 40 is made of an inorganic conductive material, which can both increase the thickness of the film layer at the edge of the display region AA and have conductivity, protect the underlying metal electrode, and enhance the reliability of the film layer.

[0036] Optionally, continue to refer to Figure 4 , the transparent film layer 40 overlaps with the first electrode layer 30. Specifically, the transparent film layer 40 is made of an inorganic conductive material and directly covers the first electrode layer 30 (metal electrode) within the second region A2 at the edge of the display region AA. The transparent film layer 40 has conductivity, can reduce the overlap resistance of the first electrode layer 30, and improve the electrical signal transmission efficiency of the first electrode layer 30. In addition, adding the transparent film layer 40 can better protect the metal film layer from being invaded by water and oxygen, improve the water and oxygen resistance of the structure of the display panel 200, and enhance the reliability of the film layer.

[0037] Optionally, the material of the inorganic conductive layer includes ITO, LiF, ZnO, TiO 2 . Specifically, the inorganic conductive layer is made of a transparent conductive material, which can not only increase the thickness of the film layer at the edge of the display region, but also ensure the overall light transmission effect of the display region.

[0038] Figure 5 is a schematic structural diagram of another display panel provided by an embodiment of the present invention. Figure 6 is Figure 5 a cross-sectional schematic diagram of a display panel along the CC' direction in Figure 7 is Figure 5 a cross-sectional schematic diagram of a display panel along the CC' direction in Figure 5 , multiple negative power buses BUS surrounding the display region AA can be set. 负 , multiple negative power buses BUS 负 alongFigure 6 extends in the Y direction to the bonding area NA' of the display panel 200 and is electrically connected to a power chip (POWER IC) (not shown in the figure). The bonding area NA' can be turned to the back of the display area AA after the display panel 200 is packaged, which is beneficial to realizing a narrow border design. It should be noted that the negative power bus BUS 负 can be arranged in the non-display area NA to provide a common voltage.

[0039] In some embodiments, referring to Figure 4 and Figure 6 , the first electrode layer 30 is located in the display area AA and the non-display area AA, and the first electrode layer 30 is electrically connected to the negative power bus BUS 负 electrically connected. In the embodiment of the present invention, the first electrode layer 30 can be directly electrically connected to the negative power bus BUS 负 electrically connected to receive the voltage signal transmitted by the negative power bus BUS 负 transmitted.

[0040] In some embodiments, referring to Figure 5 and Figure 7 , the first electrode layer 30 is located in the display area AA, and the transparent film layer 40 is electrically connected to the negative power bus BUS 负 electrically connected. In the embodiment of the present invention, the first electrode layer 30 can also be retracted inward toward the center of the display area AA, the transparent film layer 40 is overlapped with the first electrode layer 30, and the transparent film layer 40 extends to the non-display area NA and is electrically connected to the negative power bus BUS 负 electrically connected, and the transparent film layer 40 receives the voltage signal transmitted by the negative power bus BUS 负 transmitted and transmits it to the first electrode layer 30. In this way, the film thickness below the edge film layer of the inkjet printing layer IJP at the boundary of the display area AA can be increased, so that the height of the inkjet printing layer IJP is raised, achieving the purpose of slowing down the height drop. At the same time, the transparent film layer 40 has a conductive function and overlaps the first electrode layer 30 at the boundary of the display area AA, which can increase the distance L between the metal of the first electrode layer 30 and the boundaries of the inkjet printing layer IJP and the inorganic layer (CVD1, CVD2) film layers, thereby improving the water and oxygen resistance of the structure of the display panel 200.

[0041] It should be noted that in Figure 7 , due to the limitation of the interception position, the distance L between the metal boundary of the first electrode layer 30 along the X direction and the boundaries of the inkjet printing layer IJP and the inorganic layer (CVD1, CVD2) film layers is not fully shown.

[0042] It should be noted that the display panel 200 further includes a plurality of positive power buses ( Figure 5 not shown in the figure). The positive power bus and the negative power bus BUS 负 can respectively output corresponding voltage signals to be transmitted to the light-emitting device to drive the light-emitting device to emit light.

[0043] Based on the above embodiments, the display panel 200 further includes an inkjet printing layer IJP, and the inkjet printing layer IJP is located on the side of the first electrode layer 30 away from the substrate 20; along the thickness direction of the display panel 200 (shown as the Z direction in the figure), the thickness value of the transparent film layer 40 is equal to the difference between the thickness of the inkjet printing layer IJP in the first region A1 and the thickness of the inkjet printing layer IJP in the second region A2. In the embodiments of the invention, it is necessary to design the thickness value of the transparent film layer 40 according to the difference between the thickness of the inkjet printing layer IJP in the first region A1 of the display area AA and the thickness of the inkjet printing layer IJP at the boundary of the second region A2, so as to raise the film layer at the boundary of the display area AA and maintain the consistency of the film thickness in the display area AA.

[0044] Optionally, referring to Figures 3 - 7 , the thickness range of the transparent film layer 40 is 1um ± 0.1um. Exemplarily, the thickness of the inorganic conductive layer is about 1um.

[0045] Figure 8 Yes Figure 3 is a schematic cross-sectional view of another display panel along the AA' direction. Based on the above embodiments, referring to Figure 8 , at least one transparent film layer 40 includes a first transparent film layer 41 and a second transparent film layer 42, and the first transparent film layer 41 and the second transparent film layer 42 are stacked. Specifically, due to limitations such as film thickness preparation process and film thickness requirements, the transparent film layer 40 can stack multiple transparent layers. By reasonably setting the thickness and the number of film layers of the transparent film layer 40, problems such as display color difference and color halo caused by the flow of the inkjet printing layer IJP at the boundary of the display area AA and / or the bending of the profile of the encapsulation layer OC can be improved.

[0046] Based on the above embodiments, continuing to refer to Figure 8 , the first transparent film layer 41 overlaps with the first electrode layer 30, and the conductivity of the first transparent film layer 41 is greater than that of the second transparent film layer 42. In the embodiments of the present invention, the transparent film layer 40 is at least composed of the first transparent film layer 41 and the second transparent film layer 42. The first transparent film layer 41 uses a material with better conductivity, which is beneficial to reducing the contact resistance between the first transparent film layer 41 and the first electrode layer 30 and improving the reliability of the film layer.

[0047] It should be noted that the embodiments of the present invention do not limit the transparent film layer 40 to a single-layer design and adding cushion layers at other positions in the display area AA to change the film layer height. Specifically, Figure 9 is a schematic structural view of another display panel provided by the embodiments of the invention. Based on the above embodiments, referring to Figure 9, the display area AA also includes a device setting area A3, which is located in the first area A1; the transparent film layer 40 is also located on the side of the first electrode layer 30 in the first area A1 away from the base substrate 20, and extends along the first area A1 to the device setting area A3. Specifically, the device setting area A3 can be located inside or at the edge of the display area AA, and an under-screen camera, a temperature sensor, etc. can be set in the device setting area A3 to achieve image acquisition and temperature acquisition. This area is similar to the boundary of the display area AA. In some embodiments, the inkjet printing layer IJP above the first electrode layer 30 will flow at the device setting area A3, resulting in a decrease in the film thickness, resulting in problems such as display discoloration and halo. Based on this, the embodiment of the present invention also adds a transparent film layer 40 to pad the film thickness of this area at the position where the first area A1 extends to the device setting area A3, so as to keep the film thickness of the entire display area AA consistent and improve the reliability of the film.

[0048] It should be noted that the transparent film layer 40 disposed around the device setting area A3 and the transparent film layer 40 disposed in the second area A2 of the display area AA can be prepared in the same layer. The transparent film layer 40 disposed around the device setting area A3 can be prepared by a "patterning" process, and "patterning" in this article specifically refers to a non-whole-layer structure, that is, a structure in which a whole layer of material is first formed during the manufacturing process and then a specific shape is engraved.

[0049] Based on the above embodiments, continue to refer to Figure 9 , the width d3 of the transparent film layer 40 extending from the first area A1 to the device setting area A3 is less than or equal to the width d4 of the transparent film layer 40 extending from the second area A2 to the non-display area NA. Specifically, in order to prevent the transparent film layer 40 from being raised too high around the device setting area A3, it is necessary to reasonably limit the height range of the transparent film layer 40 extending from the first area A1 to the device setting area A3, that is, d3<d4, to ensure the overall thickness consistency of the display area AA.

[0050] Based on the same inventive concept, an embodiment of the present invention further provides a display device. Figure 10 A schematic diagram of the structure of a display device provided by an embodiment of the present invention. Figure 10 As shown, the display device 300 includes any display panel 200 provided in the above embodiments. Therefore, the display device 300 also has the beneficial effects of the display panel 200 in the above embodiments. The similarities can be understood by referring to the above explanation of the display panel 200, which will not be repeated below.

[0051] The display device 300 provided in the embodiment of the present invention can be Figure 10The mobile phone shown can also be any electronic product with a display function, including but not limited to the following categories: televisions, laptop computers, desktop monitors, tablet computers, digital cameras, smart bracelets, smart glasses, in-vehicle displays, industrial control devices, medical display screens, touch interaction terminals, etc. The embodiments of the present invention do not make special limitations on this.

[0052] Note that the above is only the preferred embodiment of the present invention and the technical principles applied. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described here, and various obvious changes, re-adjustments, and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments only. Without departing from the concept of the present invention, more other equivalent embodiments can be included, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A display panel, characterized in that: comprising a display area and a non-display area surrounding the display area, wherein the display area comprises a first area and a second area, and the second area surrounds the first area; substrate substrate; A first electrode layer, located on one side of the substrate; At least one transparent film layer is located on a side of the first electrode layer in the second area away from the base substrate and extends along the second area to the non-display area.

2. The display panel according to claim 1, characterized in that: The transparent film layer includes an inorganic conductive layer.

3. The display panel according to claim 2, characterized in that: The transparent film layer overlaps with the first electrode layer.

4. The display panel according to claim 3, characterized in that: The first electrode layer is located in the display area and the non-display area; the first electrode layer is electrically connected to a negative power bus.

5. The display panel according to claim 3, characterized in that: The first electrode layer is located in the display area, and the transparent film layer is electrically connected to a negative power bus.

6. The display panel according to claim 2, characterized in that: The materials of the inorganic conductive layer include ITO, LiF, ZnO, and TiO2.

7. The display panel according to claim 1, characterized in that: Also includes: An inkjet printing layer, located on a side of the first electrode layer away from the base substrate; Along the thickness direction of the display panel, the thickness of the transparent film layer is equal to the difference between the thickness of the inkjet printed layer in the first area and the thickness of the inkjet printed layer in the second area.

8. The display panel according to claim 7, characterized in that: The thickness of the transparent film layer is in the range of 1um±0.1um.

9. The display panel according to any one of claims 1 to 8, characterized in that: The at least one transparent film layer includes a first transparent film layer and a second transparent film layer, and the first transparent film layer and the second transparent film layer are stacked.

10. The display panel according to claim 9, characterized in that: The conductivity of the first transparent film layer is greater than the conductivity of the second transparent film layer.

11. The display panel according to claim 1, characterized in that: Also includes: A driving circuit layer, located on one side of the base substrate; The light-emitting layer is located on a side of the driving circuit layer away from the base substrate. The light-emitting layer includes a plurality of light-emitting units. The light-emitting units include a stacked second electrode, a light-emitting layer and the first electrode layer.

12. The display panel according to claim 1, characterized in that: Along the direction from the first region to the second region, the width of the second region is smaller than the width of the first region.

13. The display panel according to claim 11, characterized in that: The width of the second region is less than or equal to 500 μm.

14. The display panel according to claim 1, characterized in that: The display area further includes a device setting area, and the device setting area is located in the first area; The transparent film layer is also located on a side of the first electrode layer in the first region away from the substrate, and extends along the first region to the device setting region.

15. The display panel according to claim 14, characterized in that: A width of the transparent film layer extending from the first area to the device setting area is less than or equal to a width of the transparent film layer extending from the second area to the non-display area.

16. A display device, characterized in that: A display panel comprising any one of claims 1-15.

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