Pixel unit

Abstract

An embodiment of the present application discloses a pixel unit, which includes a conventional sub-pixel and a compensation sub-pixel. The conventional sub-pixel includes a first sub-pixel. The compensation sub-pixel and the conventional sub-pixel are arranged in two dimensions. The compensation sub-pixel is a non-luminous sub-pixel, wherein in the film thickness direction, the first sub-pixel includes a first anode arranged above a substrate, and the compensation sub-pixel includes at least a compensation anode arranged in the same layer as the first anode, and the compensation anode is electrically connected to the first anode in a one-to-one correspondence. By arranging the compensation sub-pixel in the pixel unit, the first driving TFT current is increased by the compensation current of the compensation sub-pixel, thereby improving the control capability of the first TFT device, and alleviating the technical problem of serious color brightness unevenness in the existing pixel unit.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a pixel unit. Background Art

[0002] Generally, OLED materials have lateral leakage current due to the stacked structure of the light-emitting device (for example, leakage current between green sub-pixels and red sub-pixels). Figure 1 The existence of this leakage current will cause the red sub-pixel to be bright when a single green sub-pixel is displayed, which will lead to color deviation at low grayscale. Therefore, the existence of this lateral leakage current has a shunting effect on the green sub-pixel, which can easily lead to the problem of brightening.

[0003] At low grayscale, see Figure 1 , the first TFT driving current I1 of the first sub-pixel = light-emitting current I3 + lateral leakage current I2. If the lateral leakage current is large, the TFT driving current of the green sub-pixel is also large. At this time, the control ability of the green sub-pixel TFT device is strong, and the color brightness unevenness is relatively slight, but the large leakage current will cause serious stealing of brightness; therefore, stealing of brightness and color brightness unevenness are a contradictory whole. According to the current structural design of the pixel unit, the problem of color brightness unevenness cannot be well solved at low leakage current.

[0004] Therefore, the existing pixel units have a serious technical problem of uneven color brightness. Summary of the invention

[0005] The embodiment of the present application provides a pixel unit, which can alleviate the technical problem of serious color brightness unevenness in existing pixel units.

[0006] An embodiment of the present application provides a pixel unit, comprising:

[0007] A regular sub-pixel, wherein the regular sub-pixel comprises a first sub-pixel, a second sub-pixel, and a third sub-pixel;

[0008] A compensation sub-pixel, wherein the compensation sub-pixel and the conventional sub-pixel are arranged in two dimensions, and the compensation sub-pixel is a non-luminous sub-pixel;

[0009] Among them, in the film thickness direction, the first sub-pixel includes a substrate and a first anode arranged above the substrate, and the compensation sub-pixel at least includes a compensation anode arranged in the same layer as the first anode, and the compensation anode is electrically connected to the first anode in a one-to-one correspondence.

[0010] Optionally, in some embodiments of the present application, the pixel unit also includes an anode layer arranged above the substrate, a pixel definition layer arranged on a side of the anode layer away from the substrate, a light-emitting material layer arranged on a side of the pixel definition layer away from the substrate, and a cathode layer arranged on a side of the light-emitting material layer away from the substrate, the anode layer includes the first anode and the compensation anode arranged in the same layer, the first anode and the light-emitting material layer are partially overlapped, the pixel definition layer covers the compensation anode, and the compensation anode and the light-emitting material layer are staggered.

[0011] Optionally, in some embodiments of the present application, the pixel unit is further provided with a through hole penetrating the pixel definition layer, and a light-emitting material layer is arranged in the through hole, wherein in the film thickness direction, the through hole is overlapped with the first anode, and the through hole is staggered with the compensation anode.

[0012] Optionally, in some embodiments of the present application, the first anode and the compensation anode are spaced apart, and the pixel unit further includes a connecting portion, one end of the connecting portion is connected to the first anode through a first connecting hole, and the other end of the connecting portion is connected to the compensation anode through a second connecting hole.

[0013] Optionally, in some embodiments of the present application, the first sub-pixel includes a first TFT device, the first TFT device includes a source and drain layer arranged above the substrate, and a planar layer arranged on a side of the source and drain layer away from the substrate, the connecting portion is arranged on the same layer as the source and drain layer, and the first connecting hole and the second connecting hole are arranged through the planar layer.

[0014] Optionally, in some embodiments of the present application, the first TFT device outputs a first TFT driving current, the second sub-pixel includes a second TFT device, the second TFT device outputs a second TFT driving current, and the first TFT driving current is greater than or equal to the second TFT driving current.

[0015] Optionally, in some embodiments of the present application, the first sub-pixel is a green sub-pixel, the second sub-pixel is a red sub-pixel, and the third sub-pixel is a blue sub-pixel. In a virtual square formed by any pixel unit, a blank area is set on one side of the blue sub-pixel, and the compensation sub-pixel is set in the blank area.

[0016] Optionally, in some embodiments of the present application, the first anode is electrically connected in parallel or in series with the compensation anode, and the compensation anode has a voltage / current dividing effect on the first anode.

[0017] Optionally, in some embodiments of the present application, the light-emitting current of the first sub-pixel is smaller than the light-emitting current of the second sub-pixel, or the light-emitting current of the first sub-pixel is smaller than the light-emitting current of the third sub-pixel.

[0018] Optionally, in some embodiments of the present application, the lateral leakage current of the first sub-pixel is 0.

[0019] Beneficial effect: By setting a compensation sub-pixel in the pixel unit, a compensation resistor is formed between the compensation anode and the cathode layer of the compensation sub-pixel, and the compensation resistor is connected to the first anode to form a compensation current. The first TFT driving current is equal to the light-emitting current of the first sub-pixel plus the compensation current. By forming the compensation current, the first driving TFT current is increased, thereby improving the control ability of the first TFT device and alleviating the technical problem of serious color unevenness in the existing pixel unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0021] Figure 1 is a schematic diagram of leakage current between a red sub-pixel and a green sub-pixel in an existing pixel unit;

[0022] Figure 2 is a top view schematic diagram of a pixel unit provided in the present application;

[0023] Figure 3 It is a cross-sectional schematic diagram of the pixel unit AA provided in the present application.

[0024] Description of reference numerals:

[0025]

[0026] DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application. In addition, it should be understood that the specific implementation methods described herein are only used to illustrate and explain the present application, and are not used to limit the present application. In the present application, unless otherwise stated, the directional words such as "upper" and "lower" used generally refer to the upper and lower parts of the device in actual use or working state, specifically the drawing direction in the accompanying drawings; while "inside" and "outside" refer to the outline of the device.

[0028] See also Figure 2 The pixel unit provided in the present application includes a conventional sub-pixel and a compensation sub-pixel 4, wherein the conventional sub-pixel includes a first sub-pixel 1, a second sub-pixel 2, and a third sub-pixel 3, and the compensation sub-pixel 4 is arranged two-dimensionally with the conventional sub-pixel, and the compensation sub-pixel 4 is a non-luminous sub-pixel, wherein, in the film thickness direction, the first sub-pixel 1 includes a substrate 10 and a first anode 1101 arranged above the substrate 10, and the compensation sub-pixel 4 at least includes a compensation anode 1102 arranged in the same layer as the first anode 1101, and the compensation anode 1102 is electrically connected to the first anode 1101 in a one-to-one correspondence.

[0029] The regular sub-pixels may include red sub-pixels, blue sub-pixels, and green sub-pixels.

[0030] In this embodiment, a compensation sub-pixel 4 is provided in the pixel unit, a compensation resistor is formed between the compensation anode 1102 of the compensation sub-pixel 4 and the cathode layer 140, and the compensation resistor is connected to the first anode 1101 to form a compensation current. The first TFT driving current I1 is equal to the light emitting current I3 of the first sub-pixel 1 plus the compensation current. By forming the compensation current, the first driving TFT current is increased, thereby improving the control ability of the first TFT device and alleviating the technical problem of severe color unevenness in the existing pixel unit.

[0031] The technical solution of the present application is now described in conjunction with specific embodiments.

[0032] The embodiment of the present application only takes the example that the first sub-pixel 1 is a green sub-pixel, and the green sub-pixel is electrically connected to the compensation sub-pixel 4, but the first sub-pixel 1 can also be a blue sub-pixel, a red sub-pixel, or other sub-pixels; the compensation sub-pixel 4 is set to be electrically connected to the sub-pixel with a smaller TFT drive current, thereby increasing the TFT drive current of the sub-pixel.

[0033] In addition, the electrical connection method between the first sub-pixel 1 and the compensation sub-pixel 4 of the present application is only described as the best or preferred implementation method. Other electrical connection methods that can increase the first TFT driving current I1 of the first sub-pixel 1 should also fall within the protection scope of the present invention and will not be repeated here.

[0034] In one embodiment, see Figure 3 The pixel unit also includes an anode layer 110 arranged above the substrate 10, a pixel definition layer 120 arranged on the side of the anode layer 110 away from the substrate 10, a light-emitting material layer 130 arranged on the side of the pixel definition layer 120 away from the substrate 10, and a cathode layer 140 arranged on the side of the light-emitting material layer 130 away from the substrate 10. The anode layer 110 includes the first anode 1101 and the compensation anode 1102 arranged in the same layer. The first anode 1101 and the light-emitting material layer 130 are partially overlapped, the pixel definition layer 120 covers the compensation anode 1102, and the compensation anode 1102 is staggered with the light-emitting material layer 130.

[0035] The pixel unit further includes a light-shielding layer 20 disposed above the substrate 10, a buffer layer 30 disposed on the side of the light-shielding layer 20 away from the substrate 10, an active layer 40 disposed on the side of the buffer layer 30 away from the substrate 10, a gate insulating layer 50 disposed on the side of the active layer 40 away from the substrate 10, a gate layer 60 disposed on the side of the gate insulating layer 50 away from the substrate 10, an interlayer insulating layer 70 disposed on the side of the gate layer 60 away from the substrate 10, a source-drain layer 80 disposed on the side of the interlayer insulating layer 70 away from the substrate 10, a passivation layer 90 disposed on the side of the source-drain layer 80 away from the substrate 10, and a planarizing layer 100 disposed on the side of the passivation layer 90 away from the substrate 10.

[0036] The anode layer 110 is disposed on a side of the planar layer 100 away from the substrate 10 .

[0037] It can be understood that by staggering the compensation anode 1102 and the light-emitting material layer 130, that is, no light-emitting material layer 130 is arranged between the compensation anode 1102 and the cathode layer 140, the compensation sub-pixel 4 does not emit light, and the compensation sub-pixel 4 does not affect the luminous brightness; at the same time, since the pixel definition layer 120 covers the compensation anode 1102, a resistor is formed between the compensation anode 1102 and the cathode layer 140. On the premise that the light-emitting current I3 of the first sub-pixel 1 remains unchanged, the first TFT driving current I1 of the first TFT device is increased, which only has the effect of improving the first TFT driving current I1 of the first sub-pixel 1, thereby improving the control ability of the first TFT device.

[0038] Furthermore, if the compensation sub-pixel 4 emits light, its light color can only be the same as the light color of the first sub-pixel 1, and the light brightness of the light color of the first sub-pixel 1 remains unchanged. Therefore, according to the light brightness = light-emitting current I3 × light-emitting efficiency, it can be seen that the light-emitting current I3 remains unchanged. Therefore, if the compensation sub-pixel 4 emits light, it cannot have the effect of increasing the first TFT driving current I1 of the first sub-pixel 1.

[0039] In this embodiment, the compensation anode 1102 and the light-emitting material layer 130 are arranged in a staggered manner so that the compensation sub-pixel 4 does not emit light, thereby improving the control capability of the first TFT device without affecting the light-emitting brightness.

[0040] In one embodiment, the pixel unit is further provided with a through hole penetrating the pixel definition layer 120, and a light-emitting material layer 130 is arranged in the through hole, wherein in the film thickness direction, the through hole and the first anode 1101 are overlapped, and the through hole and the compensation anode 1102 are staggered.

[0041] The light emitting material layer 130 is in contact with the first anode 1101 through the through hole.

[0042] It can be understood that no through hole is provided at the position of the pixel definition layer 120 corresponding to the compensation anode 1102 , and the pixel definition layer 120 between the compensation anode 1102 and the cathode layer 140 is continuously provided.

[0043] In one embodiment, the first anode 1101 and the compensation anode 1102 are spaced apart, and the pixel unit further includes a connecting portion, one end of the connecting portion is connected to the first anode 1101 through a first connecting hole, and the other end of the connecting portion is connected to the compensation anode 1102 through a second connecting hole.

[0044] It can be understood that the first anode 1101 and the compensation anode 1102 are connected by a connecting portion, and the connecting portion can be provided in the same layer as the existing metal film layer, thereby saving a preparation process of the connecting portion.

[0045] In one embodiment, the first sub-pixel 1 includes a first TFT device, which includes a source-drain electrode layer 80 disposed above the substrate 10 and a planar layer 100 disposed on a side of the source-drain electrode layer 80 away from the substrate 10, the connecting portion is disposed in the same layer as the source-drain electrode layer 80, and the first connecting hole and the second connecting hole are disposed through the planar layer 100.

[0046] The first connection hole and the second connection hole are disposed through the passivation layer 90 .

[0047] In one embodiment, the first TFT device outputs a first TFT driving current I1, the second sub-pixel 2 includes a second TFT device, the second TFT device outputs a second TFT driving current, and the first TFT driving current I1 is greater than or equal to the second TFT driving current.

[0048] It can be understood that before setting the compensation sub-pixel 4, the TFT driving current of the first sub-pixel 1 is smaller than that of other conventional sub-pixels. By setting the compensation sub-pixel 4, the first TFT driving current I1 is at least greater than the TFT driving current of any other conventional sub-pixel.

[0049] In one embodiment, see Figure 2 The first sub-pixel 1 is a green sub-pixel, the second sub-pixel 2 is a red sub-pixel, and the third sub-pixel 3 is a blue sub-pixel. In a virtual square formed by any pixel unit, a blank area 5 is provided on one side of the blue sub-pixel, and the compensation sub-pixel 4 is provided in the blank area 5.

[0050] The green sub-pixel, the red sub-pixel and the blue sub-pixel share a sub-pixel configuration, that is, the adjacent light-emitting units have SPR structures.

[0051] In this embodiment, by providing the compensation sub-pixel 4 in the blank area 5 of the pixel unit, the space utilization rate in the pixel unit is improved.

[0052] In one embodiment, the first anode 1101 and the compensation anode 1102 are electrically connected in parallel or in series, and the compensation anode 1102 has a voltage / current dividing effect on the first anode 1101 .

[0053] It can be understood that by connecting the first anode 1101 and the compensation anode 1102 in parallel, the light emitting current I3 at the first anode 1101 remains unchanged, and there is also a compensation current at the compensation anode 1102. The first TFT driving current I1 = light emitting current I3 + compensation current. By increasing the compensation current, the first TFT driving current I1 is improved.

[0054] In one embodiment, the light-emitting current I3 of the first sub-pixel 1 is smaller than the light-emitting current I3 of the second sub-pixel 2 , or the light-emitting current I3 of the first sub-pixel 1 is smaller than the light-emitting current I3 of the third sub-pixel 3 .

[0055] The first sub-pixel 1 may be a green sub-pixel, the second sub-pixel 2 may be a red sub-pixel, and the third sub-pixel 3 may be a blue sub-pixel.

[0056] The light-emitting current I3 of the green sub-pixel may be smaller than the light-emitting current I3 of the red sub-pixel, and the light-emitting current I3 of the blue sub-pixel may be smaller than the light-emitting current I3 of the blue sub-pixel.

[0057] Furthermore, the light-emitting brightness of the green sub-pixel may be greater than the light-emitting brightness of the red sub-pixel, and the light-emitting brightness of the blue sub-pixel may be greater than the light-emitting brightness of the blue sub-pixel.

[0058] In this embodiment, the first TFT driving current I1 is increased by connecting the first anode 1101 and the compensation anode 1102 in parallel or in series.

[0059] In one embodiment, the lateral leakage current I2 of the first sub-pixel 1 is less than e -12 .

[0060] Furthermore, the lateral leakage current I2 of the first sub-pixel 1 is zero.

[0061] It can be understood that by setting the lateral leakage current I2 of the first sub-pixel 1 to be less than e -12 , which can alleviate the technical problem of brightness stealing between adjacent sub-pixels of different colors; at the same time, by setting the compensation sub-pixel 4 to be electrically connected to the first sub-pixel 1, the first TFT driving current I1 of the first sub-pixel 1 is increased. When the leakage current I2 is low, a larger first TFT driving current I1 can also be guaranteed, thereby solving the technical problems of brightness stealing and uneven color brightness.

[0062] It should be noted that, in the prior art, the problem of brightness stealing is solved by reducing the lateral leakage current I2, but the reduction of the lateral leakage current I2 will cause the TFT driving current to also decrease, and the control ability of the TFT device is weak, resulting in serious color unevenness. Therefore, it is difficult for the prior art to simultaneously solve the problems of brightness stealing and color unevenness; and the present application sets a compensation sub-pixel 4, utilizes the compensation sub-pixel 4 not to emit light and its own compensation current, and improves the TFT driving current when the light-emitting current I3 is constant, which is equivalent to compensating for the defect of smaller TFT driving current caused by the reduction of the lateral leakage current I2 by adding a new compensation current.

[0063] In this embodiment, by limiting the lateral leakage current I2 to be less than e -12 , thereby alleviating the technical problem of brightness stealing between adjacent sub-pixels of different colors; further, by setting the compensation sub-pixel 4, it can also solve the technical problems of brightness stealing and uneven color brightness.

[0064] In one embodiment, the compensation anode 1102 and the first anode 1101 are integrally provided.

[0065] It can be understood that in the direction of film thickness, the compensation anode 1102 and the light-emitting material layer 130 are offset, and the compensation anode 1102 and the cathode layer 140 and the pixel definition layer 120 therebetween constitute a resistor, and the resistor will also take away part of the current of the first anode 1101, namely the compensation current. For the first sub-pixel 1, the first TFT driving current I1=luminous current I3+compensation current+lateral leakage current I2. Since the light-emitting current I3 and the lateral leakage current I2 at the first anode 1101 are unchanged, therefore, compared with the first TFT driving current I1=luminous current I3+lateral leakage current I2 in the prior art, the present application adds a compensation current, which has the effect of increasing the first TFT driving current I1.

[0066] It can be understood that the compensation anode 1102 and the first anode 1101 do not need to be connected via a connection hole, which can simplify the preparation process.

[0067] In this embodiment, the compensation anode 1102 and the first anode 1101 are integrated into one, which can further simplify the process and reduce the cost.

[0068] The present application also proposes a display panel, a display module, and a display device. The display panel, the display module, and the display device all include the above-mentioned pixel unit, which will not be described in detail here.

[0069] The pixel unit provided in this embodiment includes a conventional sub-pixel and a compensation sub-pixel 4, wherein the conventional sub-pixel includes a first sub-pixel 1, a second sub-pixel 2, and a third sub-pixel 3, wherein the compensation sub-pixel 4 and the conventional sub-pixel are arranged in two dimensions, and the compensation sub-pixel 4 is a non-luminous sub-pixel, wherein in the film thickness direction, the first sub-pixel 1 includes a substrate 10 and a first anode 1101 arranged above the substrate 10, and the compensation sub-pixel 4 at least includes a compensation anode 1102 arranged in the same layer as the first anode 1101, and the compensation anode 1102 is electrically connected to the first anode 1101 in a one-to-one correspondence; by arranging the compensation sub-pixel 4 in the pixel unit, a compensation resistor is formed between the compensation anode 1102 of the compensation sub-pixel 4 and the cathode layer 140, and the compensation resistor is connected to the first anode 1101 to form a compensation current, and the first TFT driving current is equal to the light emitting current I3 of the first sub-pixel 1 plus the compensation current, and the first driving TFT current is increased by forming the compensation current, thereby improving the control capability of the first TFT device, and alleviating the technical problem of serious color brightness unevenness in the existing pixel unit.

[0070] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0071] The pixel unit provided in the embodiment of the present application is introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A pixel unit, characterized in that: include: A regular sub-pixel, wherein the regular sub-pixel comprises a first sub-pixel, a second sub-pixel, and a third sub-pixel; A compensation sub-pixel, wherein the compensation sub-pixel and the conventional sub-pixel are arranged in two dimensions, and the compensation sub-pixel is a non-luminous sub-pixel; Wherein, in the film thickness direction, the first sub-pixel includes a substrate, a source-drain electrode layer arranged above the substrate, and a first anode arranged above the source-drain electrode layer, the compensation sub-pixel at least includes a compensation anode arranged in the same layer as the first anode, the compensation anode is electrically connected to the first anode in a one-to-one correspondence, the first anode and the compensation anode are arranged at intervals, the pixel unit also includes a connecting portion, the connecting portion is arranged in the same layer as the source-drain electrode layer, one end of the connecting portion is connected to the first anode through a first connecting hole, and the other end of the connecting portion is connected to the compensation anode through a second connecting hole, and the lateral leakage current of the first sub-pixel is less than e -12 .

2. The pixel unit according to claim 1, characterized in that: The pixel unit also includes an anode layer arranged above the substrate, a pixel definition layer arranged on the side of the anode layer away from the substrate, a light-emitting material layer arranged on the side of the pixel definition layer away from the substrate, and a cathode layer arranged on the side of the light-emitting material layer away from the substrate. The anode layer includes the first anode and the compensation anode arranged in the same layer, the first anode and the light-emitting material layer are partially overlapped, the pixel definition layer covers the compensation anode, and the compensation anode and the light-emitting material layer are staggered.

3. The pixel unit according to claim 2, characterized in that: The pixel unit is further provided with a through hole penetrating the pixel definition layer, and a light-emitting material layer is arranged in the through hole, wherein in the film thickness direction, the through hole is overlapped with the first anode, and the through hole is staggered with the compensation anode.

4. The pixel unit according to claim 3, characterized in that: The first sub-pixel includes a first TFT device, which includes a planar layer arranged on a side of the source and drain layer away from the substrate, the connecting portion is arranged in the same layer as the source and drain layer, and the first connecting hole and the second connecting hole are arranged through the planar layer.

5. The pixel unit according to claim 4, characterized in that: The first TFT device outputs a first TFT driving current, the second sub-pixel includes a second TFT device, the second TFT device outputs a second TFT driving current, and the first TFT driving current is greater than or equal to the second TFT driving current.

6. The pixel unit according to claim 5, characterized in that: The first sub-pixel is a green sub-pixel, the second sub-pixel is a red sub-pixel, and the third sub-pixel is a blue sub-pixel. In a virtual square formed by any pixel unit, a blank area is set on one side of the blue sub-pixel, and the compensation sub-pixel is set in the blank area.

7. The pixel unit according to claim 3, characterized in that: The first anode is electrically connected in parallel or in series with the compensation anode, and the compensation anode plays a role of voltage division or current division for the first anode.

8. The pixel unit according to claim 1, characterized in that: The light emitting current of the first sub-pixel is smaller than the light emitting current of the second sub-pixel, or the light emitting current of the first sub-pixel is smaller than the light emitting current of the third sub-pixel.

9. The pixel unit according to claim 1, characterized in that: The lateral leakage current of the first sub-pixel is zero.

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