Display panel and display device

Abstract

The utility model provides a display panel and a display device, relates to the field of display, and aims to solve the problem of electric leakage of transistors. The display panel comprises a substrate and a first transistor located on one side of the substrate, the first transistor comprises an active layer and a shielding layer, and the shielding layer is located on the side, close to the substrate, of the active layer; wherein the active layer comprises a plurality of first edges, at least one dimming structure is arranged on the side, facing the active layer, of the shielding layer, and for a single dimming structure, the dimming structure is used for acting on light obliquely entering the shielding layer from the side where one of the first edges is located; at least part of the acted light is emitted towards the first edge close to the incident side of the light.

Description

Technical Field

[0001] The utility model relates to the technical field of display, and particularly to a display panel and a display device. Background Art

[0002] In the existing display panel, at least part of the transistors are also provided with a shielding layer. The shielding layer is located on the side of the active layer close to the substrate and functions to shield the bottom static electricity. However, in the environment of strong light obliquely incident, part of the ambient light obliquely enters the shielding layer and is reflected by the shielding layer to the active layer. The active layer generates photo-generated carriers under the illumination, resulting in the leakage of the transistor. Summary of the Utility Model

[0003] In view of this, the utility model provides a display panel and a display device, which can effectively improve the leakage problem of the transistor.

[0004] In a first aspect, an embodiment of the utility model provides a display panel, including a substrate and a first transistor located on one side of the substrate. The first transistor includes an active layer and a shielding layer. The shielding layer is located on the side of the active layer close to the substrate. Wherein, the active layer includes a plurality of first sides, and at least one light-adjusting structure is arranged on the side of the shielding layer facing the active layer. For a single light-adjusting structure, the light-adjusting structure is used to act on the light obliquely incident into the shielding layer from the side where one of the first sides is located, so that at least part of the light after the action is emitted towards the first side close to the incident side.

[0005] In the prior art, the surface of the shielding layer facing the active layer is a flat surface. Therefore, after the ambient light obliquely enters the shielding layer from the side where one of the first sides of the active layer is located, the reflected light will obliquely shoot towards the side where the first side opposite to this first side is located. Because the distance between the active layer and the shielding layer is small, most of the reflected light will irradiate the active layer during the emission process, resulting in a large amount of light on the active layer.

[0006] However, by arranging the light-adjusting structure on the surface of the shielding layer facing the active layer in the utility model, the transmission direction of the obliquely incident light can be adjusted multiple times by using the light-adjusting structure, so that it finally returns along the original side. For example, after the ambient light obliquely enters the shielding layer from the side of the left first side of the active layer, it undergoes secondary reflection or multiple reflections on the surface of the light-adjusting structure, and the reflected light will finally be emitted back towards the side of the left first side of the active layer, thereby greatly reducing the amount of light entering the active layer, effectively solving the problem of transistor leakage caused by the reflected light, and further effectively weakening the color cast phenomenon of the display panel.

[0007] Moreover, the light-dimming structure can adjust the transmission direction of both the light incident at a small angle and the light incident at a large angle, so that the reflected light returns to the original side, reducing the probability of the reflected light irradiating the active layer. Compared with the existing improvement methods, this solution can achieve a better improvement effect on transistor leakage. And this solution does not need to adjust the area of the shielding layer and the coverage area of the anode, so it will not cause other problems such as anode short circuit.

[0008] In a feasible implementation, the shielding layer includes a plurality of light-dimming structures arranged in a circle; wherein, one light-dimming structure corresponds to one first side, and the light-dimming structure is used to act on the light obliquely incident on the shielding layer from the side where its corresponding first side is located, so that at least part of the light after the action shoots towards its corresponding first side again.

[0009] Such a setting can use a plurality of light-dimming structures to act on the light obliquely incident on the shielding layer from various directions, so that more light can finally return to the original side, and thus the light irradiating the active layer can be reduced to a greater extent, and the leakage problem of the transistor can be improved to a greater extent.

[0010] In a feasible implementation, one light-dimming structure corresponds to one first side, and the position of the light-dimming structure in the shielding layer is close to the side where its corresponding first side is located. Among them, the direction from the first side corresponding to the light-dimming structure to the opposite first side is the first direction corresponding to the light-dimming structure.

[0011] For a single light-dimming structure, the light-dimming structure includes a plurality of first reflecting surfaces and a plurality of second reflecting surfaces arranged alternately in its corresponding first direction. The distance between the first reflecting surface and the substrate increases along the first direction corresponding to the light-dimming structure, and the distance between the second reflecting surface and the substrate decreases along the first direction corresponding to the light-dimming structure. Moreover, the first reflecting surface has a first included angle with the plane parallel to the substrate, and the second reflecting surface has a second included angle with the plane parallel to the substrate, and the second included angle is smaller than the first included angle.

[0012] Under this structure, the light-dimming structure includes a plurality of protrusions arranged periodically in its corresponding first direction, and each protrusion includes an inclined first reflecting surface and an inclined second reflecting surface. At this time, the light-dimming structure can be regarded as a reflective oblique stepped grating structure. Under this light-dimming structure, the second included angle θ corresponding to the second reflecting surface is smaller, that is, compared with the first reflecting surface, the inclination degree of the second reflecting surface is greater. In this way, light in a larger angle range can be incident on the second reflecting surface, and the light incident on the second reflecting surface will undergo secondary reflection between the second reflecting surface and the first reflecting surface of another adjacent protrusion: the light incident on the second reflecting surface is reflected by the second reflecting surface to the first reflecting surface, and the light incident on the first reflecting surface is reflected again by the first reflecting surface and then returns to the original side, so as to realize the adjustment of the transmission direction of the reflected light.

[0013] In a feasible implementation, the angle between the first reflecting surface and the second reflecting surface is λ, where 89.5° ≤ λ ≤ 90.5°.

[0014] When light enters the second reflecting surface at an incident angle η1 (the normal direction corresponding to this incident angle is perpendicular to the second reflecting surface), it is reflected by the second reflecting surface and then transmitted to the first reflecting surface at an incident angle η2 (the normal direction corresponding to this incident angle is perpendicular to the first reflecting surface). According to (90° - η1) + (90° - η2) + λ = 180°, we can obtain η1 + η2 = λ. And the closer 2×η1 + 2×η2 is to 180°, that is, the closer λ is to 90°, the closer the transmission direction of the light reflected by the first reflecting surface is to the initial incident direction of the light, and the light will return closer to the original direction. By setting λ within the range of 90° ± 0.5°, the deviation between the transmission direction of the reflected light and the initial incident direction of the light can be controlled within 1°, and the control of the return direction of the reflected light is more accurate.

[0015] To make the transmission direction of the reflected light after two reflections the same as the initial incident direction of the light, further, λ can be set to 90°. At this time, the apex angle of the protrusion in the shielding layer is a right angle.

[0016] Transistor leakage will cause the problem of panel color deviation. The optional range of the second included angle θ in the dimming structure and the corresponding etching range of the dimming structure can both depend on the range of the color deviation degree.

[0017] In an optional way:

[0018] When there is no dimming structure in the shielding layer, as the incident angle of the light (this angle refers to the angle between the light transmission direction and the normal perpendicular to the substrate) increases, the incident light area reflected onto the active layer increases, the transistor leakage becomes more serious, and the panel color deviation phenomenon becomes more serious. When the incident angle of the light is large enough, the reflected light exits without passing through the active layer, and the panel color deviation phenomenon is alleviated.

[0019] In the present utility model, an angle range (ζ, ε) can be obtained by testing the product. This angle range can be the range of the incident angle of the light corresponding to when the human eye can perceive color deviation, or it can also be the range of the incident angle of the light corresponding to when the color deviation perceived by the human eye is relatively serious. ε in this range is less than α2, that is, where m is the size of the active layer in the first direction corresponding to the dimming structure after the dimming structure is set, and h is the minimum distance between the shielding layer and the active layer.

[0020] After the dimming structure is set on the shielding layer, in a feasible implementation, for a single dimming structure, the second included angle is θ, θ < 90° - ε, Among them, h is the minimum distance between the shielding layer and the active layer in the direction perpendicular to the substrate, and m is the dimension of the active layer in the first direction corresponding to the light modulation structure. In this way, light with an incident angle within the range of (ζ, ε) can fall on the second reflecting surface for secondary reflection, reducing the risk of the reflected light corresponding to this part of the light irradiating the active layer and weakening the color cast phenomenon.

[0021] In a feasible implementation manner, the light modulation structure includes a second side and a third side opposite to each other in its corresponding first direction, where the second side is located on the side close to the first side corresponding to the light modulation structure.

[0022] For a single light modulation structure, the distance between the orthographic projection of the third side on the substrate and the orthographic projection of the first side corresponding to the light modulation structure on the substrate is L, and L > h × tanε. Among them, h is the minimum distance between the shielding layer and the active layer in the direction perpendicular to the substrate, and m is the dimension of the active layer in the first direction corresponding to the light modulation structure.

[0023] At this time, the light modulation structure has a large range. When light with an incident angle within the range of (ζ, ε) enters towards the shielding layer, it can be transmitted to the light modulation structure and acted on by the light modulation structure, reducing the risk of the reflected light corresponding to this part of the light irradiating the active layer and weakening the color cast phenomenon.

[0024] In another alternative:

[0025] The active layer includes a channel, and the orthographic projection of the channel on the substrate coincides with the orthographic projection of the gate on the substrate. Since the channel has a greater impact on transistor leakage when irradiated by light, and thus has a greater impact on the color cast of the panel. Therefore, whether the reflected light irradiates the channel can be used as a basis for determining whether the color cast is serious.

[0026] When there is no light modulation structure in the shielding layer, when the incident angle of light (this angle refers to the angle between the light transmission direction and the normal line perpendicular to the substrate) is β1, the reflected light begins to irradiate the channel, and the color cast of the panel begins to worsen. Until the incident angle of light increases to β3, the reflected light begins to irradiate the outside of the channel far from the side where it enters, and the color cast of the panel begins to weaken.

[0027] When a light modulation structure is provided on the shielding layer, in a feasible implementation manner, for a single light modulation structure, the second included angle θ of the light modulation structure can be made to satisfy: θ < 90° - β1, that is Among them, h is the minimum distance between the shielding layer and the active layer in the direction perpendicular to the substrate, and p is the distance between the first side corresponding to the light modulation structure and the channel. In this way, more light can be transmitted to the second reflecting surface for secondary reflection and then return on the original side, reducing the probability of the reflected light corresponding to this part of the light irradiating the channel and weakening the color cast phenomenon.

[0028] In order to ensure that light with an incident angle within the range of (β1, β3) can all fall on the second reflection surface, the second included angle θ can further satisfy: θ < 90° - β3, that is Wherein, q is the dimension of the channel in the first direction corresponding to the light modulation structure. When the channel includes a back channel and a front channel, q can refer to the dimension of the back channel in the first direction corresponding to the light modulation structure.

[0029] In a feasible implementation manner, for a single light modulation structure, L can satisfy: At this time, the light modulation structure has a large range. When light with an incident angle within the range of (β1, β3) shines towards the shielding layer, it can be transmitted to the light modulation structure and acted on by the light modulation structure, reducing the risk that the reflected light corresponding to this part of the light irradiates the active layer and weakening the color cast phenomenon.

[0030] In a feasible implementation manner, there is a gap between at least two opposite light modulation structures, that is, at the middle position of the shielding layer, the surface of the shielding layer facing the active layer is a flat surface. The middle position of the shielding layer is far from the first side of the active layer, and the incident angle of the light that can reach this position is large. Even if there is no protrusion at this position, the light will exit from the outside of the active layer after one reflection and will not irradiate the active layer.

[0031] In a feasible implementation manner, the display panel further includes a pixel circuit. The pixel circuit includes a driving transistor and multiple switching transistors. At least some of the switching transistors are first transistors, thereby reducing the influence of the leakage current of the switching transistors on the node potential of the driving transistor, improving the stability of the working state of the driving transistor, and further avoiding the brightness shift of the sub-pixels.

[0032] In a feasible implementation manner, the switching transistor includes a threshold compensation transistor. The threshold compensation transistor is electrically connected between the second pole of the driving transistor and the gate of the driving transistor, and the threshold compensation transistor is a first transistor.

[0033] Since the influence of transistor leakage on the emission brightness of the sub-pixels is mainly reflected in the emission stage, and the threshold compensation transistor is cut off during the emission stage. If the threshold compensation transistor generates an off-state leakage current, the influence will be greater and will have an obvious impact on the gate potential of the driving transistor. Therefore, in the present invention, at least the threshold compensation transistor is designed as a first transistor to more greatly reduce the influence of transistor leakage on the working state of the pixel circuit, and further effectively improve the color cast problem of the panel.

[0034] In a second aspect, based on the same inventive concept, an embodiment of the present invention further provides a display device, and the display device includes the above-mentioned display panel. Description of the Drawings

[0035] To more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0036] Figure 1 It is a schematic structural diagram of a display panel in the prior art;

[0037] Figure 2 It is another schematic structural diagram of a display panel in the prior art;

[0038] Figure 3 It is still another schematic structural diagram of a display panel in the prior art;

[0039] Figure 4 It is a schematic structural diagram of a display panel provided by an embodiment of the present invention;

[0040] Figure 5 It is a schematic structural diagram of an active layer and a shielding layer provided by an embodiment of the present invention;

[0041] Figure 6 It is Figure 5 A cross-sectional view along the A1 - A2 direction;

[0042] Figure 7 It is a schematic partial structure diagram of a display panel provided by an embodiment of the present invention;

[0043] Figure 8 It is a schematic diagram of light transmission provided by an embodiment of the present invention;

[0044] Figure 9 It is a process flow chart of manufacturing a shielding layer provided by an embodiment of the present invention;

[0045] Figure 10 It is another schematic diagram of light transmission provided by an embodiment of the present invention;

[0046] Figure 11 It is a schematic structural diagram of a dimming structure provided by an embodiment of the present invention;

[0047] Figure 12 It is another schematic structural diagram of an active layer and a shielding layer provided by an embodiment of the present invention;

[0048] Figure 13 It is still another schematic diagram of light transmission provided by an embodiment of the present invention;

[0049] Figure 14Another schematic diagram of the dimming structure 8 provided by the embodiment of the present invention;

[0050] Figure 15 A schematic diagram of a pixel circuit provided by the embodiment of the present invention;

[0051] Figure 16 A schematic diagram of a display device provided by the embodiment of the present invention. Detailed implementation manners

[0052] To better understand the technical solutions of the present invention, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0053] It should be clear that the described embodiments are only part of the embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0054] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "the" and "said" used in the embodiments of the present invention and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0055] It should be understood that the term " / and" used herein is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, a and / or b may represent: a exists alone, a and b exist simultaneously, and b exists alone. In addition, the character " / " in this article generally represents an "or" relationship between the associated objects before and after.

[0056] As Figure 1 shown, Figure 1 A schematic diagram of a display panel in the prior art. The display panel includes a substrate 101 and a first transistor 102 located on one side of the substrate 101. The first transistor 102 includes an active layer 103, a gate 104, a first pole 105, a second pole 106, and a shielding layer 107. Among them, the shielding layer 107 is located on the side of the active layer 103 close to the substrate 101 and is used to shield the bottom static electricity.

[0057] However, in some environments where strong light is incident obliquely, for example, when a user uses the screen under sunlight outdoors, the ambient light will enter the light shielding layer 107 obliquely and be reflected by the light shielding layer 107 to the active layer 103. Photo-generated carriers are generated in the active layer 103 under the action of light, resulting in leakage current in the transistor. Especially when the transistor in the pixel circuit leaks electricity, it will further cause the brightness of the sub-pixel to decay, and then cause color deviation of the display panel. In practical applications, affected by factors such as the anode coverage area, the light-receiving area of the transistors in different color sub-pixels is different, and the brightness of the green sub-pixel decays more, so the overall screen will be pinkish, seriously affecting the display effect.

[0058] To solve the above problems, in one way, as Figure 2 shown, Figure 2 is another schematic structural diagram of the display panel in the prior art. A part of the light shielding layer 107 can be removed to reduce the amount of ambient light entering the light shielding layer 107, thereby reducing the reflection of the light shielding layer 107. However, this structure can only avoid the reflection of light incident at a small angle, and the light incident at a slightly larger angle can still be normally transmitted to the light shielding layer 107 and be reflected by the light shielding layer 107 to the active layer 103. Moreover, after removing a part of the light shielding layer 107, the risk of leakage due to the influence of the external electric field may increase instead.

[0059] Or, in another way, as Figure 3 shown, Figure 3 is still another schematic structural diagram of the display panel in the prior art. The coverage area of the anode 108 can also be increased to use the anode to block a part of the obliquely incident light and prevent it from being transmitted to the light shielding layer 107. However, this structure also cannot avoid the reflection of light incident at a slightly larger angle, and moreover, increasing the anode coverage area will also increase the risk of short circuit between the anodes.

[0060] In response to this, the present utility model proposes a display panel, and the display panel can be an Organic Light Emitting Diode (OLED) display panel. As Figures 4 - 6 shown, Figure 4 is a schematic structural diagram of the display panel provided by the embodiment of the present utility model, Figure 5 is a schematic structural diagram of the active layer and the light shielding layer provided by the embodiment of the present utility model, Figure 6 is Figure 5 a cross-sectional view along the A1-A2 direction. The display panel includes a substrate 1 and a first transistor 2 located on one side of the substrate 1. The first transistor 2 includes an active layer 3, a gate 4, a first electrode 5, a second electrode 6, and a light shielding layer 7.

[0061] Among them, the first transistor 2 can be a Low Temperature Poly-silicon (LTPS) transistor, and its active layer 3 includes a polysilicon material. Combining Figure 5 and Figure 11 , the active layer 3 includes a plurality of first sides 19.

[0062] One of the first pole 5 and the second pole 6 is the source electrode, and the other is the drain electrode.

[0063] The shielding layer 7 is located on the side of the active layer 3 close to the substrate 1 and can include a metal material. At least one light-dimming structure 8 is provided on the side of the shielding layer 7 facing the active layer 3. For a single light-dimming structure 8, combining Figure 5 , the light-dimming structure 8 is used to act on the light obliquely incident on the shielding layer 7 from the side where one of the first sides 19 is located, so that at least part of the light after the action is projected back toward the first side 19 close to its incident side. That is, the light-dimming structure 8 can change the transmission direction of the light obliquely incident on the shielding layer 7, so that the regulated light finally returns to the original side. From Figure 5 's orientation, the light obliquely incident on the shielding layer 7 from the side of the first side 19 on the left of the active layer 3 is acted on by the light-dimming structure 8, and its reflected light will be projected back toward the first side 19 on the left of the active layer 3. The light obliquely incident on the shielding layer 7 from the side of the first side 19 on the right of the active layer 3 is acted on by the light-dimming structure 8, and its reflected light will be projected back toward the first side 19 on the right of the active layer 3.

[0064] In the prior art, the surface of the shielding layer facing the active layer is a flat surface. Therefore, when ambient light obliquely enters the shielding layer from the side where one of the first sides of the active layer is located, the reflected light will be obliquely projected toward the side where the first side on the opposite side of the first side is located. Because the distance between the active layer and the shielding layer is small, most of the reflected light will irradiate the active layer during the emission process, resulting in the active layer being greatly illuminated.

[0065] However, in the present utility model, by providing the light-dimming structure 8 on the surface of the shielding layer 7 facing the active layer, the light-dimming structure 8 can be used to adjust the transmission direction of the obliquely incident light multiple times, so that it finally returns to the original side. For example, referring to Figure 5 , when ambient light obliquely enters the shielding layer 7 from the side of the first side 19 on the left of the active layer 3, secondary reflection or multiple reflections occur on the surface of the light-dimming structure 8, and the reflected light will finally be projected back toward the first side 19 on the left of the active layer 3, thereby greatly reducing the amount of light entering the active layer 3, effectively solving the problem of transistor leakage caused by reflected light, and further effectively weakening the color cast phenomenon of the display panel.

[0066] Moreover, the light-dimming structure 8 can adjust the transmission direction of both the light incident at a smaller angle and the light incident at a larger angle, so that the reflected light returns to the original side, reducing the probability of the reflected light irradiating the active layer 3. Compared with the existing improvement methods, this solution can achieve a better improvement effect on transistor leakage. In addition, this solution does not need to adjust the area of the shielding layer 7 and the coverage area of the anode, so it will not cause other problems such as anode short circuit.

[0067] In a feasible implementation, referring again to Figure 5 , the shielding layer 7 includes a plurality of light-dimming structures 8, and the plurality of light-dimming structures 8 are arranged in a circle. Among them, one light-dimming structure 8 corresponds to one first side 19, and the light-dimming structure 8 is used to act on the light obliquely incident on the shielding layer 7 from the side where its corresponding first side 19 is located, so that at least part of the light after the action is projected back towards its corresponding first side 19.

[0068] Exemplarily, in one structure, the active layer 3 includes four first sides 19, Figure 5 and the four first sides 19 are respectively denoted by reference numerals 19-1, 19-2, 19-3, and 19-4 in Figure 5 . Correspondingly, the shielding layer 7 includes four light-dimming structures 8,

[0069] and the four light-dimming structures 8 are respectively denoted by reference numerals 8-1, 8-2, 8-3, and 8-4 in

[0070] , and the four light-dimming structures 8 are arranged in a circle. Among them, the light-dimming structure 8-1 corresponds to the first side 19-1, and is used to act on the light obliquely incident on the shielding layer 7 from the side where the first side 19-1 is located, so that at least part of the light after the action is projected back towards the first side 19-1; the light-dimming structure 8-2 corresponds to the first side 19-2, and is used to act on the light obliquely incident on the shielding layer 7 from the side where the first side 19-2 is located, so that at least part of the light after the action is projected back towards the first side 19-2; the light-dimming structure 8-3 corresponds to the first side 19-3, and is used to act on the light obliquely incident on the shielding layer 7 from the side where the first side 19-3 is located, so that at least part of the light after the action is projected back towards the first side 19-3; the light-dimming structure 8-4 corresponds to the first side 19-4, and is used to act on the light obliquely incident on the shielding layer 7 from the side where the first side 19-4 is located, so that at least part of the light after the action is projected back towards the first side 19-4.

[0071] In a feasible implementation, in combination with Figure 5 and Figure 7 ,Figure 7 This is a partial structural schematic diagram of a display panel provided by an embodiment of the present invention. One dimming structure 8 corresponds to one first side 19. The position of the dimming structure 8 in the light shielding layer 7 is close to the side where its corresponding first side 19 is located. Among them, the direction from the first side 19 corresponding to the dimming structure 8 to the opposite first side 19 is the first direction x corresponding to the dimming structure 8.

[0072] It can be understood that the first sides 19 corresponding to different dimming structures 8 are different, and the directions from these first sides 19 to the opposite first sides 19 are also different. Therefore, the first directions x corresponding to different dimming structures 8 are different. Refer to Figure 5 , for clear illustration, the first direction corresponding to the dimming structure 8-1 is denoted by the reference numeral x1, the first direction corresponding to the dimming structure 8-2 is denoted by the reference numeral x2, the first direction corresponding to the dimming structure 8-3 is denoted by the reference numeral x3, and the first direction corresponding to the dimming structure 8-4 is denoted by the reference numeral x4.

[0073] In one structure, the dimming structure 8 can be arranged along the outer edge of the light shielding layer 7. At this time, one outer edge of the dimming structure 8 can be regarded as coinciding with one outer edge of the light shielding layer 7.

[0074] For a single dimming structure 8, the dimming structure 8 includes a plurality of first reflecting surfaces 10 and a plurality of second reflecting surfaces 11 arranged alternately in the first direction x corresponding to the dimming structure 8. The distance between the first reflecting surface 10 and the substrate 1 increases along the first direction x corresponding to the dimming structure 8, and the distance between the second reflecting surface 11 and the substrate 1 decreases along the first direction x corresponding to the dimming structure 8. That is to say, in a single dimming structure 8, the first reflecting surface 10 inclines towards the substrate 1 away from the first side 19 corresponding to the dimming structure 8, while the second reflecting surface 11 inclines towards the substrate 1 close to the first side 19 corresponding to the dimming structure 8. Moreover, the first reflecting surface 10 has a first included angle γ with the plane parallel to the substrate 1, and the second reflecting surface 11 has a second included angle θ with the plane parallel to the substrate 1. The second included angle θ is smaller than the first included angle γ. It can be understood that both the first included angle γ and the second included angle θ are greater than 0.

[0075] Under this structure, the dimming structure 8 includes a plurality of protrusions 15 arranged periodically in its corresponding first direction x, and each protrusion 15 includes an inclined first reflecting surface 10 and an inclined second reflecting surface 11. At this time, the dimming structure 8 can be regarded as a reflective oblique stepped grating structure. Under this dimming structure 8, the second included angle θ corresponding to the second reflecting surface 11 is smaller, that is, compared with the first reflecting surface 10, the inclination degree of the second reflecting surface 11 is greater, so that light within a larger angle range can be incident on the second reflecting surface 11, and the light incident on the second reflecting surface 11 will undergo secondary reflection between the second reflecting surface 11 and the first reflecting surface 10 of another adjacent protrusion 15: As Figure 8 shown Figure 8 is a schematic diagram of light transmission provided by an embodiment of the present invention. The light incident on the second reflecting surface 11 is reflected by the second reflecting surface 11 to the first reflecting surface 10, and the light incident on the first reflecting surface 10 is reflected again by the first reflecting surface 10 and then returns to the original side, so as to adjust the transmission direction of the reflected light.

[0076] When forming this reflective oblique stepped grating structure, a structure with a flat surface can be formed first, and then serrated protrusions 15 are processed on this structure through several layers of mask processes.

[0077] For example, this kind of serrated protrusion 15 can be formed by the homogeneous mask method used for processing blazed gratings, as Figure 9 shown Figure 9 is a process flow chart for manufacturing a shielding layer 7 provided by an embodiment of the present invention. The process for forming the shielding layer 7 may include:

[0078] Step S1: Form a to-be-processed shielding layer 7' with a flat surface.

[0079] Step S2: Coat a photoresist 13 on the to-be-processed shielding layer 7'.

[0080] Step S3: Pattern the photoresist 13 by using an exposure and development process to form a plurality of spaced-apart glue portions 14, wherein the cross-section of the glue portion 14 in a direction perpendicular to the substrate 1 and parallel to the first direction x corresponding to the dimming structure 8 is trapezoidal.

[0081] Step S4: Adopt normal-incidence ion beam etching to form a plurality of to-be-processed protrusions 15' on the side of the to-be-processed shielding layer 7' away from the substrate 1. The cross-section of the to-be-processed protrusion 15' in a direction perpendicular to the substrate 1 and parallel to the first direction x corresponding to the dimming structure 8 is trapezoidal, and an inclined surface of the to-be-processed protrusion 15' is the first reflecting surface 10.

[0082] Step S5: Remove the glue portion 14.

[0083] Step S6: Use inclined ion beam etching to obliquely remove a part of the to-be-processed protrusion 15' to form the second reflection surface 11, so that the serrated protrusion 15 can be processed and formed.

[0084] It should be noted that this reflective oblique stepped grating structure can also be regarded as a blazed grating. Most of the light is incident on the blazed grating in a direction equivalent to non-normal incidence. However, since the overall diffraction efficiency of the blazed grating for incoherent light is relatively low, the effect on the diffracted light can be ignored, and the reflected light is still the main one.

[0085] In a feasible implementation manner, referring back to Figure 8 , the angle between the first reflection surface 10 and the second reflection surface 11 is λ, and 89.5° ≤ λ ≤ 90.5°.

[0086] When light is incident on the second reflection surface 11 at an incident angle η1 (the normal direction corresponding to this incident angle is perpendicular to the second reflection surface 11), it is reflected by the second reflection surface 11 and then transmitted to the first reflection surface 10 at an incident angle η2 (the normal direction corresponding to this incident angle is perpendicular to the first reflection surface 10). According to (90° - η1) + (90° - η2) + λ = 180°, it can be obtained that η1 + η2 = λ. And the closer 2×η1 + 2×η2 is to 180°, that is, the closer λ is to 90°, the closer the transmission direction of the light reflected by the first reflection surface 10 is to the initial incident direction of the light, and the light will return more closely in the original direction. By setting λ within the range of 90° ± 0.5°, the deviation between the transmission direction of the reflected light and the initial incident direction of the light can be controlled within 1°, and the control of the return direction of the reflected light is more accurate.

[0087] To make the transmission direction of the reflected light after secondary reflection the same as the initial incident direction of the light, further, λ can be set to 90°. At this time, the apex angle of the protrusion 15 in the shielding layer 7 is a right angle.

[0088] As mentioned above, transistor leakage will cause panel color deviation problems. The optional range of the second included angle θ in the dimming structure 8 and the etching range corresponding to the dimming structure 8 can both depend on the range of the color deviation degree. In this regard, the present invention provides two optional methods.

[0089] In the first optional method:

[0090] When the dimming structure 8 is not provided in the shielding layer 7, as Figure 10 shown, Figure 10Another schematic diagram of light transmission provided by the embodiment of the present invention. As the incident angle of light (this angle refers to the angle between the light transmission direction and the normal line perpendicular to the substrate 1) increases, the area of the incident light reflected onto the active layer 3 increases, and the transistor leakage becomes more serious, and the panel color deviation phenomenon becomes more serious. When the incident angle of light is large enough, the reflected light exits without passing through the active layer 3, and the panel color deviation phenomenon is alleviated.

[0091] In the present invention, an angle range (ζ, ε) can be obtained by testing the product. This angle range can be the incident angle range of light corresponding to when the human eye can perceive color deviation, or it can also be the incident angle range of light corresponding to when the color deviation perceived by the human eye is relatively serious. ε in this range is less than α2, that is, where m is the size of the active layer 3 in the first direction x corresponding to the light-adjusting structure 8 after the light-adjusting structure 8 is set, and h is the minimum distance between the shielding layer 7 and the active layer 3.

[0092] After the light-adjusting structure 8 is set on the shielding layer 7, the optional range of the second included angle θ is as Figure 11 shown. Figure 11 This is a schematic structural diagram of the light-adjusting structure 8 provided by the embodiment of the present invention. For a single light-adjusting structure 8, the second included angle θ in the light-adjusting structure 8 can be made to satisfy: θ < 90° - ε. In this way, the light with an incident angle in the range (ζ, ε) can all fall on the second reflection surface 11 for secondary reflection, reducing the risk that the reflected light corresponding to this part of the light irradiates the active layer 3 and weakening the color deviation phenomenon.

[0093] Regarding the etching range corresponding to the light-adjusting structure 8, in combination with Figure 5 and Figure 11 , the light-adjusting structure 8 includes a second side 30 and a third side 31 arranged along the first direction x corresponding to the light-adjusting structure 8. Among them, the second side 30 is located on the side close to the first side 19 corresponding to the light-adjusting structure 8.

[0094] For a single light-adjusting structure 8, the distance between the orthographic projection of the third side 31 on the substrate 1 and the orthographic projection of the first side 19 corresponding to the light-adjusting structure 8 on the substrate 1 is L, and L satisfies: L > h × tan ε. At this time, the light-adjusting structure 8 has a larger range, and the light with an incident angle in the range (ζ, ε) can be transmitted to the light-adjusting structure 8 when it irradiates towards the shielding layer 7, and is acted on by the light-adjusting structure 8, reducing the risk that the reflected light corresponding to this part of the light irradiates the active layer 3 and weakening the color deviation phenomenon.

[0095] In the second optional method:

[0096] As Figure 12 shown. Figure 12Another structural schematic diagram of the active layer and the shielding layer provided by the embodiment of the present invention. The active layer 3 includes a channel 16, and the orthographic projection of the channel 16 on the substrate 1 coincides with the orthographic projection of the gate 4 on the substrate 1. Since the channel 16 has a greater impact on the leakage of the transistor when irradiated by light, and thus has a greater impact on the color shift of the panel. Therefore, whether the reflected light irradiates the channel 16 can be used as a basis for determining whether the color shift is serious.

[0097] When the dimming structure 8 is not provided in the shielding layer 7, as Figure 13 shown, Figure 13 Another light transmission schematic diagram provided by the embodiment of the present invention. When the incident angle of light (this angle refers to the angle between the light transmission direction and the normal line perpendicular to the substrate 1) is β1, the reflected light begins to irradiate the channel 16, and the color shift of the panel begins to worsen. Until the incident angle of light increases to β3, the reflected light begins to irradiate outside the channel 16, and the color shift of the panel begins to weaken.

[0098] When the dimming structure 8 is provided on the shielding layer 7, regarding the optional range of the second angle θ, as Figure 14 shown, Figure 14 Another structural schematic diagram of the dimming structure 8 provided by the embodiment of the present invention. For a single dimming structure 8, the second angle θ of the dimming structure 8 can be satisfied: θ < 90° - β1, that is where h is the minimum distance between the shielding layer 7 and the active layer 3 in the direction perpendicular to the substrate 1, and p is the distance between the first side 19 corresponding to the dimming structure 8 and the channel 16. In this way, more light can be transmitted to the second reflection surface 11 for secondary reflection and then return to the original side, reducing the probability that the reflected light corresponding to this part of the light irradiates the channel 16 and weakening the color shift phenomenon.

[0099] In order to make the light with the incident angle in the range of (β1, β3) all fall on the second reflection surface 11, the second angle θ can further satisfy: θ < 90° - β3, that is where q is the dimension of the channel 16 in the first direction x corresponding to the dimming structure 8. When the channel 16 includes a back channel and a front channel, q can refer to the dimension of the back channel in the first direction x corresponding to the dimming structure 8.

[0100] Regarding the etching range corresponding to the dimming structure 8, combined with Figures 12 - 14 , for a single dimming structure 8, L can satisfy: At this time, the dimming structure 8 has a larger range. When the light with the incident angle in the range of (β1, β3) irradiates the shielding layer 7, it can be transmitted to the dimming structure 8 and acted on by the dimming structure 8, reducing the risk that the reflected light corresponding to this part of the light irradiates the active layer 3 and weakening the color shift phenomenon.

[0101] It should be noted that doping regions are also provided on both sides of the channel 16. When the light modulation structure 8 is arranged in the arrangement direction of the doping region and the channel 16, the p involved in the θ and L formulas corresponding to the light modulation structure 8 can be understood as the size of the doping region in the first direction x corresponding to the light modulation structure 8. Regarding the multiple first sides 19 of the active layer 3, two of the first sides 19 can be regarded as the edges of the two doping regions away from the channel 16, and the other two first sides 19 can be regarded as the outer edges of the circuit where the active layer 3 is located.

[0102] In addition, it should be noted that the L defined above is the distance between the third side 31 of the light modulation structure 8 and the first side 19 of the active layer 3, and its size can be used to reflect the distance that the third side 31 of the light modulation structure 8 extends inward, that is, it can be used to reflect the etching range corresponding to the light modulation structure 8. When the orthographic projection of the shielding layer 7 on the substrate 1 coincides with the orthographic projection of the active layer 3 on the substrate 1, L can be equal to the etching range corresponding to the light modulation structure 8, that is, equal to the size of the light modulation structure 8 in the first direction x. When the size of the shielding layer 7 in the first direction x is greater than the size of the active layer 3 in the first direction x, L can be less than the etching range corresponding to the light modulation structure 8. When the size of the shielding layer 7 in the first direction x is less than the size of the active layer 3 in the first direction x, L can be greater than the etching range corresponding to the light modulation structure 8.

[0103] In a feasible implementation manner, referring again to Figure 5 , there is a gap between at least two opposite light modulation structures 8, that is, at the middle position of the shielding layer 7, the surface of the shielding layer 7 facing the active layer 3 is a flat surface. The middle position of the shielding layer 7 is far from the first side 19 of the active layer 3, and the incident angle of the light that can reach this position is large. Even if there is no protrusion 15 at this position, the light will be emitted from the outside of the active layer 3 after one reflection and will not irradiate the active layer 3.

[0104] In a feasible implementation manner, as Figure 15 shown, Figure 15 is a schematic structural diagram of a pixel circuit 20 provided by an embodiment of the present invention. The display panel further includes a pixel circuit 20. The pixel circuit 20 includes a driving transistor T0, multiple switching transistors, and a storage capacitor C. Among them, at least some of the switching transistors can be set as the first transistor 2, so as to reduce the influence of the leakage current of the switching transistors on the node potential of the driving transistor, improve the stability of the working state of the driving transistor, and further avoid the brightness shift of the sub-pixels.

[0105] In one structure, the switching transistors may specifically include a gate reset transistor T1, a data writing transistor T2, a threshold compensation transistor T3, an anode reset transistor T4, a first light emission control transistor T5, and a second light emission control transistor T6.

[0106] Among them, the gate of the gate reset transistor T1 is electrically connected to the first scan line Scan1, the first pole of the gate reset transistor T1 is electrically connected to the reset signal line Vref, and the second pole of the gate reset transistor T1 is electrically connected to the gate of the driving transistor T0.

[0107] The gate of the data writing transistor T2 is electrically connected to the second scan line Scan2, the first pole of the data writing transistor T2 is electrically connected to the data line Data, and the second pole of the data writing transistor T2 is electrically connected to the first pole of the driving transistor T0.

[0108] The gate of the threshold compensation transistor T3 is electrically connected to the second scan line Scan2, the first pole of the threshold compensation transistor T3 is electrically connected to the second pole of the driving transistor T0, and the second pole of the threshold compensation transistor T3 is electrically connected to the gate of the driving transistor T0.

[0109] The gate of the anode reset transistor T4 is electrically connected to the first scan line Scan1, the first pole of the anode reset transistor T4 is electrically connected to the reset signal line Vref, and the second pole of the anode reset transistor T4 is electrically connected to the D anode of the light emitting element.

[0110] The gate of the first light emission control transistor T5 is electrically connected to the light emission control line Emit, the first pole of the first light emission control transistor T5 is electrically connected to the power supply line PVDD, and the second pole of the first light emission control transistor T5 is electrically connected to the first pole of the driving transistor T0.

[0111] The gate of the second light emission control transistor T6 is electrically connected to the light emission control line Emit, the first pole of the second light emission control transistor T6 is electrically connected to the second pole of the driving transistor T0, and the second pole of the second light emission control transistor T6 is electrically connected to the anode of the light emitting element D.

[0112] In addition, the first electrode plate of the storage capacitor C is electrically connected to the power supply line PVDD, and the second electrode plate of the storage capacitor C is electrically connected to the gate of the driving transistor T0.

[0113] Furthermore, the switching transistor includes the threshold compensation transistor T3. As described above, the threshold compensation transistor T3 is electrically connected between the second pole and the gate of the driving transistor T0. In the present utility model, the threshold compensation transistor T3 can be set as the first transistor 2.

[0114] Since the impact of transistor leakage on the sub-pixel emission brightness is mainly reflected in the emission stage, and the threshold compensation transistor T3 is turned off during the emission stage, if the threshold compensation transistor T3 generates an off-state leakage current, the impact will be greater and will significantly affect the gate potential of the driving transistor. Therefore, in the present invention, at least the threshold compensation transistor T3 is designed as the first transistor 2 to more greatly reduce the impact of transistor leakage on the working state of the pixel circuit 20, thereby effectively improving the panel color deviation problem.

[0115] In addition, referring again to Figure 4 , the display panel further includes a barrier layer 21 located between the shielding layer 7 and the substrate 1, a buffer layer 22 located between the shielding layer 7 and the active layer 3, a gate insulating layer 23 located between the active layer 3 and the gate 4, an interlayer dielectric layer 23 located between the gate and the first electrode 5 and the second electrode 6, and a planarization layer 25 located on the side of the first electrode 5 and the second electrode 6 away from the substrate 1, and other structures.

[0116] Based on the same concept, the embodiment of the present invention further provides a display device, as Figure 16 shown, Figure 16 is a schematic structural diagram of the display device provided by the embodiment of the present invention. The display device includes the above-mentioned display panel 100. Among them, the specific structure of the display panel 100 has been described in detail in the above embodiments and will not be repeated here. Of course, Figure 16 the display device shown is only for illustrative purposes, and the display device can be any electronic device with a display function, such as a mobile phone, a tablet computer, a notebook computer, an e-book reader, or a television.

[0117] For the same or similar parts between the various embodiments in this specification, reference can be made to each other. In particular, for the device embodiments and the terminal embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can refer to the description in the method embodiments.

Claims

1. A display panel, characterized in that: It comprises a substrate and a first transistor located at one side of the substrate, wherein the first transistor comprises an active layer and a shielding layer, and the shielding layer is located at a side of the active layer close to the substrate; In which, the active layer includes multiple first edges, and at least one dimming structure is arranged on the side of the shielding layer facing the active layer. For a single dimming structure, the dimming structure is used to act on the light that is obliquely incident into the shielding layer from the side where one of the first edges is located, so that at least part of the light after the action is emitted toward the first edge close to its incident side.

2. The display panel according to claim 1, characterized in that: The shielding layer includes a plurality of dimming structures, and the plurality of dimming structures are arranged around a circle; Among them, one dimming structure corresponds to one first edge, and the dimming structure is used to act on the light obliquely incident into the shielding layer from the side where the corresponding first edge is located, so that at least part of the light after the action is emitted toward the corresponding first edge again.

3. The display panel according to claim 1, characterized in that: One dimming structure corresponds to one first edge, and the dimming structure is located in the shielding layer close to the side where the first edge corresponding to it is located, wherein the direction from the first edge corresponding to the dimming structure to the first edge on the opposite side is the first direction corresponding to the dimming structure; For a single dimming structure, the dimming structure includes a plurality of first reflecting surfaces and a plurality of second reflecting surfaces alternately arranged in the first direction corresponding to the dimming structure, the distance between the first reflecting surface and the substrate increases along the first direction corresponding to the dimming structure, the distance between the second reflecting surface and the substrate decreases along the first direction corresponding to the dimming structure, and a first angle is formed between the first reflecting surface and a plane parallel to the substrate, a second angle is formed between the second reflecting surface and a plane parallel to the substrate, and the second angle is smaller than the first angle.

4. The display panel according to claim 3, characterized in that: An angle between the first reflecting surface and the second reflecting surface is λ, and 89.5°≤λ≤90.5°.

5. The display panel according to claim 4, characterized in that: λ=90°.

6. The display panel according to claim 3, characterized in that: For a single dimming structure, the second angle is θ, θ<90°-ε, Wherein, h is the minimum distance between the shielding layer and the active layer in a direction perpendicular to the substrate, and m is the size of the active layer in the first direction corresponding to the dimming structure.

7. The display panel according to claim 3, characterized in that: The dimming structure comprises a second side and a third side opposite to each other in the first direction corresponding to the dimming structure, wherein the second side is located on a side close to the first side corresponding to the dimming structure; For a single dimming structure, the distance between the orthographic projection of the third side on the substrate and the orthographic projection of the first side corresponding to the dimming structure on the substrate is L, L>h×tanε, Wherein, h is the minimum distance between the shielding layer and the active layer in a direction perpendicular to the substrate, and m is the size of the active layer in the first direction corresponding to the dimming structure.

8. The display panel according to claim 3, characterized in that: The active layer includes a channel; For a single dimming structure, the second angle is θ, Wherein, h is the minimum distance between the shielding layer and the active layer in a direction perpendicular to the substrate, and p is the distance between the first side corresponding to the dimming structure and the channel.

9. The display panel according to claim 3, characterized in that: The active layer includes a channel; The dimming structure comprises a second side and a third side opposite to each other in the first direction corresponding to the dimming structure, wherein the second side is located on a side close to the first side corresponding to the dimming structure; For a single dimming structure, the distance between the orthographic projection of the third side on the substrate and the orthographic projection of the first side corresponding to the dimming structure on the substrate is L, Wherein, p is the distance between the first side corresponding to the dimming structure and the channel, and q is the size of the channel in the first direction corresponding to the dimming structure.

10. The display panel according to claim 2, characterized in that: There is a gap between at least two opposing dimming structures.

11. The display panel according to claim 1, characterized in that: The display panel further includes a pixel circuit, which includes a driving transistor and a plurality of switch transistors, at least some of which are the first transistors.

12. The display panel according to claim 11, characterized in that: The switch transistor includes a threshold compensation transistor, the threshold compensation transistor is electrically connected between the second electrode of the drive transistor and the gate of the drive transistor, and the threshold compensation transistor is the first transistor.

13. A display device, characterized in that: It comprises the display panel as claimed in any one of claims 1 to 12.

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