CN119012827A

CN119012827A - Display panel and display device

Info

Publication number: CN119012827A
Application number: CN202411112674.0A
Authority: CN
Inventors: 尹姝璐
Original assignee: Wuhan Tianma Microelectronics Co Ltd
Current assignee: Wuhan Tianma Microelectronics Co Ltd
Priority date: 2024-08-13
Filing date: 2024-08-13
Publication date: 2024-11-22
Also published as: WO2026036484A1

Abstract

The invention discloses a display panel and a display device, wherein the display panel comprises a substrate base plate, and a pixel circuit layer and a light-emitting function layer which are sequentially laminated on one side of the substrate base plate, wherein the pixel circuit layer comprises a plurality of pixel circuits, and the pixel circuits comprise a plurality of thin film transistors; the insulation layer is positioned between the pixel circuit layer and the luminous functional layer, and at least part of the area of the insulation layer is provided with a grating structure; the grating structure comprises a plurality of shading parts and light transmission parts which are periodically arranged along a first direction, and the first direction is parallel to the plane of the substrate. A grating structure is arranged in at least part of the area of the insulating layer between the pixel circuit layer and the light-emitting functional layer, so that the interference of external light on the thin film transistor is reduced by utilizing the grating structure, and the problem of color cast of light leakage flow of the driving transistor is solved.

Description

Display panel and display device

Technical Field

The embodiment of the invention relates to the technical field of display, in particular to a display panel and a display device.

Background

At present, in the display panel products, under sunlight or external light, due to leakage current and redness of a thin film transistor (Thin Film Transistor, TFT) of the display panel, the display effect and application of the display panel are affected.

Disclosure of Invention

The invention provides a display panel and a display device, which solve the problem of light leakage flow and color deviation of a driving transistor by arranging a grating structure in at least part of the area of an insulating layer between a pixel circuit layer and a light-emitting functional layer and reducing the interference of external light rays on a thin film transistor by using the grating structure.

In a first aspect, an embodiment of the present invention provides a display panel, including a substrate, and a pixel circuit layer and a light-emitting functional layer that are sequentially stacked on one side of the substrate, where the pixel circuit layer includes a plurality of pixel circuits, and the pixel circuits include a plurality of thin film transistors;

an insulating layer positioned between the pixel circuit layer and the light-emitting functional layer, wherein at least part of the insulating layer is provided with a grating structure;

The grating structure comprises a plurality of shading parts and light transmission parts which are periodically arranged along a first direction, and the first direction is parallel to the plane where the substrate is located.

In a second aspect, an embodiment of the present invention further provides a display apparatus, where the display apparatus includes the display panel provided in the first aspect.

According to the display panel provided by the embodiment of the invention, the grating structure is arranged in at least part of the area of the insulating layer between the pixel circuit layer and the luminous functional layer, and the periodically arranged grating structure is used for shielding the light rays incident from the outside with a large visual angle, so that the large-angle light rays cannot irradiate the active layer of the thin film transistor of the pixel circuit layer, the interference of the outside light rays on the thin film transistor is reduced, the problem that the light leakage and the color deviation of the driving transistor are caused by the insufficient shielding of the metal layer on the large-angle light rays is solved, and the display effect of the display panel is improved.

Drawings

FIG. 1 is a schematic cross-sectional view of a display panel according to the prior art;

Fig. 2 is a top view of a display panel according to an embodiment of the present invention;

FIG. 3 is a schematic cross-sectional view of a display panel along aa' in FIG. 2;

FIG. 4 is another cross-sectional view of the display panel of FIG. 2 along the aa' direction;

FIG. 5 is an enlarged schematic view of a portion of the grating structure in the M region of FIG. 3;

FIG. 6 is an enlarged schematic view of a portion of the grating structure in the M region of FIG. 3;

FIG. 7 is an enlarged schematic view of a portion of the grating structure in the M region of FIG. 3;

FIG. 8 is an enlarged schematic view of a portion of the grating structure in the M region of FIG. 3;

FIG. 9 is an enlarged schematic view of the M-area portion of the grating structure of FIG. 3;

FIG. 10 is an enlarged top view of a display panel of the type shown in FIG. 2 at region N;

FIG. 11 is an enlarged top view of an alternative display panel shown in FIG. 2 at region N;

FIG. 12 is a schematic cross-sectional view of a light shielding portion of a grating structure according to the present application;

Fig. 13 to 14 are schematic cross-sectional views of light shielding portions of two other grating structures according to the present application;

FIG. 15 is a schematic cross-sectional view of another display panel along aa' in FIG. 2;

FIG. 16 is a schematic cross-sectional view of another display panel along aa' in FIG. 2;

FIG. 17 is a schematic cross-sectional view of another display panel along aa' in FIG. 2;

FIG. 18 is a schematic cross-sectional view of another display panel along aa' in FIG. 2;

FIG. 19 is a schematic cross-sectional view of another display panel along aa' in FIG. 2;

FIG. 20 is a schematic diagram of a 7T1C pixel circuit according to the present application;

FIG. 21 is a circuit layout of an actual membrane layer structure of the pixel circuit of FIG. 17;

Fig. 22 is a top view of a display device according to an embodiment of the present invention.

Detailed Description

The invention is described in further detail below with reference to the drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting thereof. It should be further noted that, for convenience of description, only some, but not all of the structures related to the present invention are shown in the drawings.

Fig. 1 is a schematic cross-sectional view of a display panel according to the prior art. As shown in fig. 1, in the display process of the display panel 100 provided in the prior art, since the external light S0 is incident into the display panel 100, the active layer of the thin film transistor (Thin Film Transistor, TFT) in the driving circuit film 102 is illuminated, which is prone to generate light effects, such as generating leakage current, causing a reduction in driving voltage, and further causing a reduction in the light-emitting brightness of the light-emitting device 10, color shift is generated after the light-emitting device 10 emits light to mix colors, and the display effect of the display panel is affected.

In some existing applications, as shown in fig. 1, a metal film layer such as an anode metal layer RE or other metal line layers (e.g. a signal line in a driving circuit film layer, not shown in fig. 1) of the light emitting device 10 is often adopted for shielding, however, the shielding of the metal film layer has a size limitation, the current shielding design can only shield light with a smaller incident angle α, for example, sunlight with an incident angle α < 45 °, when the incident angle α > 45 °, the sunlight can obliquely enter the TFT from a gap of the metal film layer, so that TFT leakage current is caused, that is, the existing metal film layer cannot realize full-face shielding, and still has the problem of illumination color cast, and finally, the display of the display panel 100 is affected.

It should be noted that, the film layers of the display panel 100 further include other film layers, such as the substrate 101, the driving circuit layer 102, the light emitting function layer 103, the packaging layer (not shown in fig. 1), and the like, which are not shown here.

In fig. 1, an angle between the external light S0 and a normal line of a plane of the display panel 100 is referred to as an incident angle α.

Based on the technical problems, the embodiment of the invention provides a display panel, which comprises a substrate, and a pixel circuit layer and a light-emitting functional layer which are sequentially stacked on one side of the substrate, wherein the pixel circuit layer comprises a plurality of pixel circuits, and the pixel circuits comprise a plurality of thin film transistors; the insulation layer is positioned between the pixel circuit layer and the luminous functional layer, and at least part of the area of the insulation layer is provided with a grating structure; the grating structure comprises a plurality of shading parts and light transmission parts which are periodically arranged along a first direction, and the first direction is parallel to the plane of the substrate.

By adopting the technical scheme, the grating structure is arranged in at least part of the area of the insulating layer between the pixel circuit layer and the luminous functional layer, and the periodically arranged grating structure is utilized to shield the light rays incident from the outside with a large visual angle, so that the large-angle light rays cannot irradiate the active layer of the thin film transistor of the pixel circuit layer, the interference of the outside light rays on the thin film transistor is reduced, the problem that the light leakage and the color deviation of the driving transistor are caused by the insufficient shielding of the metal layer on the large-angle light rays is solved, and the normal display of the display panel is ensured.

The foregoing is the core idea of the present invention, and the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without making any inventive effort are intended to fall within the scope of the present invention.

Fig. 2 is a top view of a display panel according to an embodiment of the present invention; FIG. 3 is a schematic cross-sectional view of a display panel along aa' in FIG. 2; FIG. 4 is a schematic cross-sectional view of a display panel along aa' in FIG. 2. As shown in fig. 2 to 4, the display panel 200 provided in the embodiment of the present invention includes a substrate 20, and a pixel circuit layer 30 and a light emitting function layer 50 sequentially stacked on one side of the substrate 20, where the pixel circuit layer 30 includes a plurality of pixel circuits (not shown in fig. 3 and 4), and the pixel circuits include a plurality of thin film transistors 31; an insulating layer 40 between the pixel circuit layer 30 and the light emitting function layer 50, at least a partial region of the insulating layer 40 being provided with a grating structure 41; the grating structure 41 includes a plurality of light shielding portions 41a and light transmitting portions 41b periodically arranged in a first direction (X direction or Y direction in the drawing).

The first direction (X direction or Y direction in the drawing) is parallel to the plane of the substrate 20, and the present application is exemplified by the first direction alone in the drawing.

Specifically, referring to fig. 2, the display panel 200 includes an OLED (Organic LIGHT EMITTING Diode) display panel, an AMOLED (Active-Matrix Organic LIGHT EMITTING Diode) display panel, a QLED (Quantum Dot LIGHT EMITTING Diodes) display panel, an LED (LIGHT EMITTING Diode) display panel, a Micro LED (Micro LIGHT EMITTING Diode) display panel, a Mini LED (MINI LIGHT EMITTING Diode, sub-millimeter light emitting Diode) display panel, and the like, and the type of the display panel 200 is not particularly limited in the embodiment of the present invention.

The display panel 200 includes a display area (ACTIVE AREA, AA) for normally displaying a picture, and a non-display area NA at least partially surrounding a frame area of the display area AA, such as a peripheral wiring area, for signal line arrangement, packaging of the display panel, and the like.

Referring to fig. 3 and 4, the substrate 20 of the display panel 200 may be a rigid material such as glass or silicon wafer, or a flexible material such as ultra-thin glass, metal foil or polymer plastic material, and the flexible or rigid substrate 20 may block oxygen and moisture to prevent moisture or impurities from diffusing into the display panel through the substrate 20. A pixel circuit layer 30 and a light emitting function layer 50 are provided on one side of the substrate 20. The pixel circuit layer 30 includes pixel circuits (not shown in fig. 3 and 4), and the pixel circuits may be 2T1C, 4T1C, 7T2C, 8T1C, 8T2C, and other circuit structures, and the type of the pixel circuits is not particularly limited in the embodiment of the present application. The pixel circuit includes a plurality of thin film transistors (Thin Film Transistor, TFT) 31, storage capacitors, metal wirings, and other film structures (not shown in fig. 3 and 4), one electrode of the thin film transistor 31 is electrically connected to one electrode of the light emitting element 51 in the light emitting functional layer 50, and the pixel circuit layer 30 is used for providing a driving voltage to the light emitting element 51 to drive the light emitting element 51 to emit light.

Illustratively, the drain electrode of the thin film transistor 31 is electrically connected to the anode electrode of the light-emitting element 51.

The grating structure (grating) refers to an optical device formed by a large number of parallel slits with equal widths and equal intervals.

With continued reference to fig. 3 and 4, at least one insulating layer 40 is further included between the pixel circuit layer 30 and the light emitting function layer 50, and may be an organic layer such as polyimide, polyethylene naphthalate, polycarbonate, polyarylate, polyethersulfone, or the like. A grating structure 41 is provided in at least a partial region of the insulating layer 40, and the grating structure 41 is composed of a plurality of light shielding portions 41a and light transmitting portions 41b periodically provided in the X direction in the drawing. The light shielding portion 41a refers to a light-permeable region, and the light transmitting portion 41b refers to a light-impermeable region.

In the embodiment of the application, the grating structure 41 is arranged in the backlight area of the light-emitting functional layer 50, namely, on one side facing away from the light-emitting side, on the one hand, the normal light-emitting of the light-emitting functional layer 50 can be prevented from being blocked by the grating structure 41; on the other hand, when the external light S0 is incident into the display panel 200 at the large viewing angle β, the light shielding portion 41a has an absorbing or shielding effect on the large viewing angle β, and can block the light from being irradiated onto the thin film transistor 31 in the pixel circuit layer 30, so as to avoid the leakage of the thin film transistor 31, ensure the stable driving voltage and stable light-emitting brightness of the light-emitting element 51, and the outgoing light from the light-emitting element 51 can be mixed normally, thereby improving the shielding range of the large viewing angle β, improving the color cast problem of the display panel 200, and ensuring the normal display of the display panel 200.

Wherein, compared with the prior art shown in FIG. 1, in FIG. 3 and FIG. 4, β is greater than or equal to α > 45 °. As shown in fig. 3, a grating structure 41 may be provided in the entire insulating layer 40; or a grating structure 41 is arranged in the central thickness area of the insulating layer 40 to block the light with a large viewing angle.

It should be noted that, the display panel 200 provided in the embodiment of the present invention further includes other film layers, such as an encapsulation layer, and the plurality of film layers cooperate to realize the normal display of the display panel, which are clearly understood and understood by those skilled in the art on the basis of the prior art, and are not further shown here.

In summary, in the display panel provided by the embodiment of the invention, the grating structure is arranged in at least part of the area of the insulating layer between the pixel circuit layer and the light-emitting functional layer, and the periodically arranged grating structure is used for shielding the light rays incident from the outside with a large visual angle, so that the large-angle light rays cannot irradiate the active layer of the thin film transistor of the pixel circuit layer, the interference of the outside light rays on the thin film transistor is reduced, and the problem that the light leakage and the color deviation of the driving transistor are caused due to the insufficient shielding of the metal layer on the large-angle light rays is solved, thereby improving the display effect of the display panel.

With continued reference to fig. 3 and 4, the orthographic projection of the grating structure 41 on the substrate 20 at least partially overlaps with the orthographic projection of at least part of the thin film transistor 31 on the substrate 20, based on the above-described embodiments.

Specifically, in the Z direction in fig. 3 and fig. 4, at least a portion of the grating structure 4 is disposed directly above the thin film transistor 31, and the light transmitting portion 41b of the grating structure 41 can absorb or block the external light incident from the small viewing angle α and the external light incident from the large viewing angle β, so that compared with the structure in fig. 3 and/or fig. 4 in which the grating structure 4 is not disposed directly above the thin film transistor 31, the interference of the external light S0 to the thin film transistor 31 can be avoided, the light leakage of the thin film transistor 31 is reduced, and the color cast is improved, thereby improving the display effect.

FIG. 5 is an enlarged schematic view of a portion of the grating structure in the M region of FIG. 3; FIG. 6 is an enlarged schematic view of a portion of the grating structure in the M region of FIG. 3; FIG. 7 is an enlarged schematic view of a portion of the grating structure in the M region of FIG. 3; FIG. 8 is an enlarged schematic view of a portion of the grating structure in the M region of FIG. 3; fig. 9 is an enlarged schematic view of the M-region partial grating structure of fig. 3.

On the basis of the above-described embodiment, as shown in fig. 3 to 6, in the first direction (X direction in the drawing), the distance between the adjacent two light shielding portions 41a is L; the height of the light shielding portion 41a is H in the second direction (Z direction in the drawing), where h≡l, which is perpendicular to the plane (XY plane in the drawing) on which the substrate 20 is located.

Specifically, as described with reference to fig. 5, the shielding angle range θ of the light shielding portion 41a is defined to satisfy tan θ=h/L, and as illustrated with reference to fig. 6, when h=l is set, the incident angle θ″ is a critical angle at which the light shielding portion 41a shields external light, θ "=45°, θ ' < θ" < θ ' "is not more than 90 °, that is, light having an incident angle range of 0 to θ" is transmitted through the light transmitting portion 41b between the adjacent two light shielding portions 41a, and light having an incident angle range of θ "toθ '" is shielded by the light shielding portion 41a, whereby the shielding angle range θ of the light shielding portion 41a is [45 °,90 ° ].

Referring to fig. 7, when H > L is set, the incident angle θ″ is a critical angle at which the light shielding portions 41a block the external light, that is, the light having the incident angle range of 0 to θ″ passes through the light transmitting portions 41b between the adjacent two light shielding portions 41a, and the light having the incident angle range of θ″ to θ' "is blocked by the light shielding portions 41 a. Wherein θ "" < θ' "is less than or equal to 90 °, θ" =45°, whereby the shielding angle range θ of the light shielding portion 41a is [ θ "",90 ° ]. By setting H.gtoreq.L, the shielding angle range of the shielding part 41a for the external light with the incident angle larger than or equal to 45 degrees is larger, and the shielding effect is better.

Referring to fig. 8, if H < L is set, the incident angle θ '"is a critical angle at which the light shielding portions 41a block the external light, that is, the light having the incident angle range of 0 to θ'" passes through the light transmitting portions 41b between the adjacent two light shielding portions 41a, and the light having the incident angle range of θ '"to θ'" is blocked by the light shielding portions 41 a. In this structural design, the shielding angle range θ of the shielding portion 41a is [ θ "" ',90 ° ] and θ ' < θ "" ' < θ "< 90 ° and θ" =45°, and the shielding effect is poor because the shielding angle range is small although the shielding portion 41a shields the external light incident angle of 45 ° or more.

On the basis of the above-described embodiment, with continued reference to fig. 3 to 9, the light shielding portion 41a is formed of a nano carbon black material doped in the insulating layer 40.

Specifically, referring to fig. 3 to 9, the insulating layer 40 may be doped with a nano carbon black material to form a periodically arranged light shielding portion 41a, and the light shielding is performed by using a black grating arrangement, so as to absorb and shield external light, and reduce interference of the external light S0 on the thin film transistor 31.

In other embodiments, the material of the light shielding portion 41a may be black light absorbing material, such as ink, and the embodiment of the present application is not particularly limited.

As an example, with continued reference to fig. 3, the thickness of the insulating layer 40 in the display panel 200 is 2.0 μm, and in this layer, the grating structure 41 with h=l=2.0 μm is set with the nano carbon black structure as a material, so that the shielding of the external light S0 with the incident angle greater than or equal to 45 ° can be achieved.

On the basis of the above-described embodiment, as shown in fig. 3 and 9, the front projection shape of the light shielding portion 41a in the first cross section is a trapezoid, and the bottom side length of the trapezoid on the side close to the light emitting function layer 50 is smaller than the bottom side length of the trapezoid on the side close to the pixel circuit layer 30; the first cross section (XZ plane in the drawing) is parallel to the first direction X and perpendicular to the plane of the substrate 20.

The grating height refers to the height of the opaque region, i.e., the height of the light shielding portion 41a along the Z direction in the drawing.

Specifically, referring to fig. 9, on the basis of h+_l provided in the above embodiment, the rationalized design may be performed in the grating height direction of the light shielding portion 41a, where the light shielding portion 41a is arranged along the Z direction in the figure, and the cross section of the light shielding portion 41a in the XZ plane in the figure is trapezoidal, and it may also be understood that the light shielding portion 41a is small and large in the light shielding cross section on the XY plane in the figure, the light incident from a small view angle is blocked at the bottom of the light shielding portion 41a, the light incident from a large view angle is blocked at the top of the light shielding portion 41a, and the bottom of the light shielding portion 41a is prepared larger while ensuring a larger light shielding angle range, which is beneficial to blocking stray light, reflected light, refracted light, and so on, thereby reducing the external light entering the pixel circuit layer 30.

Fig. 10 is an enlarged top view of a display panel of the type of N region of fig. 2.

On the basis of the above-described embodiments, referring to fig. 10, the grating structure 41 includes a one-dimensional grating.

The one-dimensional grating refers to a periodic structure with only one arrangement direction, such as equally spaced barriers or equally wide and equidistant transparent strips arranged in parallel.

Specifically, referring to fig. 10, a one-dimensional grating with periodic arrangement is adopted, which is beneficial to shielding the light with a large viewing angle incident along the X direction in the figure, and reducing the interference of external light S0 on the thin film transistor 31.

Fig. 11 is an enlarged top view of another display panel of the N region of fig. 2.

On the basis of the above embodiment, referring to fig. 11, the grating structure 41 includes a two-dimensional grating, and the first direction X includes at least a first sub-direction X1 and a second sub-direction X2 intersecting each other; along the first sub-direction X, the light shielding portion 41a and the light transmitting portion 41b are disposed along the first period d 1; along the second sub-direction X2, the light shielding portion 41a and the light transmitting portion 41b are disposed along the second period d 2.

In fig. 11, the first sub-direction X1 may be understood as any direction parallel to the plane of the substrate 20, i.e. the X direction in the drawings of the above embodiment; the second sub-direction X2 may also be understood as a direction parallel to the plane of the substrate 20 and intersecting the first sub-direction X1, i.e. the Y-direction in the drawings of the above embodiments.

In some embodiments, as shown in fig. 11, the first sub-direction X1 and the second sub-direction X2 are orthogonal.

Wherein, the two-dimensional grating refers to a periodic structure with two arrangement directions, such as an equidistant barrier or an equidistant transparent belt with equal width which are arranged in parallel and vertically, and the periodic structure consists of a series of parallel lines or uneven surfaces.

The grating period refers to the length from one refractive index change point to an adjacent refractive index change point. The grating period is related to the grating constant d, which is an important parameter of the grating, representing the distance between the two reticles of the grating.

Referring to fig. 11, the sum of the lengths of the adjacent light shielding portions 41a and the light transmitting portions 41b is set to the first period d1 in the X1 direction in the drawing, which is advantageous in blocking the large-angle-of-view light incident in the X1 direction in the drawing; along the X2 direction in the figure, the sum of the lengths of the adjacent light shielding portions 41a and the light transmitting portions 41b is set to be the second period d2, which is favorable for shielding the large-viewing-angle light incident along the X2 direction in the figure, so that the blocking of the grating structure 41 to the large-viewing-angle light incident at each angle is comprehensively improved, the interference of external light to the thin film transistor 31 is avoided, the color cast problem is further improved, and the display effect is improved.

In some embodiments, with continued reference to FIG. 11, the first period d1 is set equal to the second period d2.

Specifically, with continued reference to fig. 11, the first period d1 of the grating structure 41 along the X1 direction in the drawing is set to be equal to the second period d2 along the X2 direction in the drawing, which is beneficial to reducing the difficulty of preparing the two-dimensional grating, reducing the projection area of the light shielding portion 41a on the substrate 20, and flexibly setting the light shielding portion in the insulating layer 40; on the other hand, the light shielding portion 41a is beneficial to uniformly shielding the external light rays incident at all angles, so that the possibility that the external light rays reach the thin film transistor 31 is reduced, and the interference of residual light rays on the thin film transistor 31 is avoided.

On the basis of the embodiment, the front projection of the shading part of the grating structure on the substrate can be designed to shade external light rays with various incident angles.

Fig. 12 is a schematic cross-sectional view of a light shielding portion of a grating structure according to the present application.

In some embodiments, as shown in fig. 12, the light shielding portion 41a of the grating structure 41 has a front projection shape of a plurality of polygons densely arranged on the substrate 20.

Specifically, referring to fig. 12, two adjacent light shielding portions 41a may be densely arranged, so that the orthographic projection area of the light transmitting portion 41b on the substrate 20 is reduced, for example, the light shielding portions 41a are densely arranged with regular hexagonal cross sections to form a shielding barrier, so as to block the incident light rays at various angles.

Fig. 13 to 14 are schematic cross-sectional views of light shielding portions of two other grating structures according to the present application.

In some embodiments, with continued reference to fig. 10-14, the polygon includes a regular triangle, a parallelogram, or a regular hexagon.

Specifically, the size, position, etc. of the light shielding portion 41a of the grating structure 41 can be appropriately set according to the position of the thin film transistor 31 in the pixel circuit layer 30, the size, position, etc. of the light emitting element 51 in the light emitting function layer 50. For example, as shown in fig. 10, the light shielding portion 41a is rectangular in front projection on the base substrate 20; as shown in fig. 11, the light shielding portion 41a is projected in a square shape on the base substrate 20; as shown in fig. 12, the light shielding portion 41a is orthographically projected on the substrate 20 as a regular hexagon; as shown in fig. 13, the light shielding portion 41a is orthographic projected on the substrate 20 as a regular triangle; as shown in fig. 14, the light shielding portion 41a is projected in a circular shape on the substrate 20, and so on, and more embodiments are not shown here one by one.

It should be noted that, the same or different grating structures 41 may be used in different areas of the display panel 200, and for example, in the densely arranged areas of the thin film transistors 31, more densely arranged light shielding portions 41a are provided; in the region where the thin film transistor 31 is sparse, the light shielding portion 41a and the like are arranged only for the region above the thin film transistor 31, thereby reducing the process preparation difficulty, the production cost and the like.

In this way, by reasonably setting the size and position of the light shielding portion 41a, the light shielding portion 41a can not only shield the incident light of more external views, but also adapt to the structural arrangement of the thin film transistor 31 and the light emitting element 51 in different areas of the display panel 200, thereby reducing the manufacturing cost of the display panel.

FIG. 15 is a schematic cross-sectional view of another display panel along aa' in FIG. 2; FIG. 16 is a schematic cross-sectional view of another display panel along aa' in FIG. 2.

The display panel 200 further includes the planarization layer 60 between the pixel circuit layer 30 and the light emitting function layer 50 on the basis of the above-described embodiment. Wherein the planarization layer has a planarization effect, and the material may include, but is not limited to, benzocyclobutene or acrylic organic material or inorganic material including silicon nitride, and may have a single-layer, double-layer or multi-layer structure.

In some embodiments, as shown in fig. 15, the insulating layer 40 is located between the planarization layer 60 and the pixel circuit layer 30; in some embodiments, with continued reference to fig. 16, an insulating layer 40 is positioned between the planarizing layer 60 and the light-emitting functional layer 50.

Specifically, as shown in fig. 15, the insulating layer 40 may be one insulating film layer closest to the light emitting function layer 50 in the pixel circuit layer 30; as shown in fig. 16, an insulating film layer may be additionally added on the surface of the pixel circuit layer 30 before the planarization layer 60 is prepared, and the material includes, but is not limited to, inorganic materials such as silicon oxide or silicon nitride, or organic materials. By providing the grating structure 41 in at least a partial region of the insulating layer 40, the external light S0 ranging from a small viewing angle to a large viewing angle can be blocked, and the light leakage phenomenon of the thin film transistor 31 can be reduced.

As described above with continued reference to fig. 3 and 4, the display panel 200 further includes a planarization layer 60 between the pixel circuit layer 30 and the light-emitting function layer 50, and the insulating layer 40 is multiplexed as the planarization layer 60.

Specifically, with continued reference to fig. 3, in the Z direction of the drawing, the grating structure 41 penetrates through the planarization layer 60 and is disposed in at least a partial region of the planarization layer 60; with continued reference to fig. 4, in the Z direction of the drawing, the grating structure 41 is located in a central region of the planarization layer 60. Thus, no new functional film layer is needed to be added, the grating structure 41 is arranged in the existing planarization layer 60, and the barrier for external light S0 is formed between the pixel circuit layer 30 and the light-emitting functional layer 50, so that the thickness of the display panel 200 is controlled, the number of film layers is reduced, and the requirement of ultrathin application of the display panel 20 is met.

FIG. 17 is a schematic cross-sectional view of another display panel along aa' in FIG. 2; FIG. 18 is a schematic cross-sectional view of another display panel along aa' in FIG. 2; FIG. 19 is a schematic cross-sectional view of another display panel along aa' in FIG. 2.

On the basis of the above-described embodiment, referring to fig. 17 and 18, the display panel 200 further includes a light shielding metal layer 70 located on the side of the thin film transistor 31 near the light-emitting function layer 50; the orthographic projection of the light shielding metal layer 70 on the substrate 20 at least partially overlaps with the orthographic projection of at least part of the thin film transistor 31 on the substrate 20; the front projection of the light shielding metal layer 70 onto the substrate 20 at least partially overlaps with the front projection of the grating structure 41 onto the substrate 20.

Specifically, referring to fig. 17 and 18, on the basis of providing the grating structure 41 between the pixel circuit layer 30 and the light-emitting functional layer 50, a light-shielding metal layer 70 may be further added between the pixel circuit layer 30 and the light-emitting functional layer 50, so as to strengthen the blocking of the incident light from the outside and prevent the light from entering the pixel circuit layer 30.

On the basis of the above-described embodiment, with continued reference to fig. 17 and 18, the light-emitting functional layer 50 includes a plurality of light-emitting elements 51, the light-emitting elements 51 including a first electrode layer 51a, a light-emitting layer 51b, and a second electrode layer 51c disposed in this order in a direction away from the substrate 20; the pixel circuit layer 30 includes at least two metal wiring layers 31. The first metal wiring layer 32 is the metal wiring layer 31 closest to the light emitting functional layer 50 in the pixel circuit layer 30.

Specifically, as shown in fig. 17-19, in the embodiment of the present invention, the light emitting element 51 is illustrated by taking an OLED as an example, the first electrode layer 51a may be an anode of the light emitting element 51, the second electrode layer 51c is a cathode of the light emitting element 51, the second electrode layer 51c may be a whole layer structure or a non-whole layer structure, and the first electrode layer 51a and the second electrode layer 51c may be made of transparent conductive materials, for example, ITO (indium tin oxide), IZO (indium zinc oxide), ITO/Ag/ITO, or the like; or the materials of the first electrode layer 51a and the second electrode layer 51c are different, the second electrode layer 51c is made of a transparent conductive material, and the first electrode layer 51a may be made of a metal such as aluminum (Al), silver (Ag), chromium (Cr), titanium (Ti), tantalum (Ta), molybdenum (Mo), or an alloy thereof. The light-emitting material of the light-emitting layer 51b may be a low-molecular or high-molecular organic material.

Further, the structure of the pixel circuit layer 30 is described below by taking a top gate type thin film transistor of the OLED display panel in fig. 17 as an example, and the pixel circuit layer 30 of the display panel 200 further includes an active layer 311 disposed on the substrate 20; a gate insulating layer 312 on the active layer 311; a gate electrode 313 on the gate insulating layer 312; a first interlayer insulating layer 314 on the gate electrode 313, a capacitor layer 315 on the first interlayer insulating layer 314, and a second interlayer insulating layer 316 on the capacitor layer 315, wherein the interlayer insulating layer may be formed by insulating an inorganic layer of silicon oxide or silicon nitride, etc.; a source electrode 317 and a drain electrode 318 on the second interlayer insulating layer 316, the source electrode 317 and the drain electrode 318 being electrically connected to the source region and the drain region, respectively, through contact holes (not shown in fig. 17), the source electrode 317 and the drain electrode 318 may be Cr, pt, ru, au, ag, mo, al, W, cu and/or a metal of AlNd, or a metal including ITO, GIZO, GZO, IZO (InZnO) or AZO (AlZnO) or a conductive oxide; a passivation layer 319 and an insulating layer 40 and a planarization layer 60 on the source electrode 317 and the drain electrode 318 of the thin film transistor 31.

The first electrode layer 51a is electrically connected to one electrode of the thin film transistor 31 through the via hole D of the insulating layer 40. Taking fig. 17 as an example, the drain electrode 318 of the thin film transistor 31 is electrically connected to the first electrode layer 51a (anode) of the light emitting element 51 through the via D, and typically the pixel circuit layer 30 includes at least two metal wiring layers, for example, a bottom metal wiring layer where the gate 313 is located, for setting a scan signal line and transmitting a scan signal; the middle metal wiring layer where the source electrode 317 and the drain electrode 318 are located is used for setting a data signal line to transmit a data signal; and at least one first metal wiring layer 32 between the drain electrode 318 and the first electrode layer 51a (anode), for ensuring the transmission of a via connection current signal, so as to drive the light emitting element 51 to emit light.

In some embodiments, as shown in fig. 17, the light shielding metal layer 70 is the same layer as the first electrode layer 51 a.

Specifically, referring to fig. 17, when the first electrode layer 51a is prepared, a "patterning" preparation process may be adopted, and meanwhile, the light-shielding metal layer 70 is prepared, so as to obtain a shielding barrier of the light-shielding metal layer 70 under the upper grating structure 41, and the light-shielding metal layer 70 firstly blocks the external incident light, and the grating structure 41 blocks the external incident light leaked into the light-shielding metal layer 70;

In some embodiments, as shown in fig. 18, the light shielding metal layer 70 is the same layer as the first metal wiring layer 32.

Specifically, referring to fig. 18, when the first metal routing layer 32 is prepared, a "patterning" preparation process may be used to prepare the light-shielding metal layer 70 at the same time, so as to obtain a shielding barrier with the light-shielding metal layer 70 on the lower side and the grating structure 41 on the upper side, and the grating structure 41 first blocks the external incident light, and the light-shielding metal layer 70 blocks the external incident light leaking into the grating structure 41.

In some embodiments, as shown in fig. 19, a portion of the light shielding metal layer 70 is in the same layer as the first electrode layer 51a, and a portion of the light shielding metal layer 70 is in the same layer as the first metal wiring layer 32.

Referring to fig. 19, in preparing the first metal routing layer 32 and the first electrode layer 51a, a "patterning" preparation process may be used, and simultaneously, the light shielding metal layer 70 is prepared, and in the Z direction in the drawing, the light shielding metal layer 70 and the grating structure 41 overlap and interleave with each other, and simultaneously, block incident light from the outside.

As in the above embodiment, the light shielding metal layer 70 and the grating structure 41 play a role of double-layer shielding, enhancing the blocking of external light, reducing the incidence of external light into the pixel circuit layer 30 to the maximum extent, and improving the problems of light leakage and color cast.

It should be noted that "patterning" herein specifically refers to a non-whole layer structure, that is, a structure in which a whole layer of material is formed first and then a specific shape is engraved in the manufacturing process; or the whole layer of material is formed first in the manufacturing process and then the pattern structure with other preparation process shapes is adopted.

FIG. 20 is a schematic diagram of a 7T1C pixel circuit according to the present application; fig. 21 is a circuit layout of an actual membrane layer structure of the pixel circuit of fig. 20.

On the basis of the above-described embodiments, with continued reference to fig. 3, 4, and 15 to 21, the thin film transistor 31 includes a driving transistor T3 and a threshold compensation transistor T4; the first end 1 of the driving transistor T3 is electrically connected with the first end 1 of the threshold compensation transistor T4, and the control end 2 of the driving transistor T3 is electrically connected with the second end of the threshold compensation transistor T4; the threshold compensation transistor T4 is used for performing threshold compensation on the driving transistor T3; the orthographic projection of the grating structure 41 on the substrate 20 at least partially overlaps with the orthographic projection of the threshold compensation transistor T4 on the substrate 20.

As an example, referring to fig. 20, the pixel circuit provided in this embodiment includes 7 transistors and a capacitor (7T 1C), which are respectively a first transistor T1, a second transistor T2, a driving transistor T3, a threshold compensation transistor T4, a fifth transistor T5, a sixth transistor T6, and a seventh transistor T7, and a storage capacitor Cst. As shown in fig. 17 and 21, the pixel circuit provided in this embodiment includes an active layer 311, a bottom metal wiring layer 33, an intermediate metal wiring layer 34, and a first metal wiring layer 32 that are sequentially stacked on one side of a substrate 20, where the active layer 311 is used to form conductive channels of a first transistor T1, a second transistor T2, a driving transistor T3, a threshold compensation transistor T4, a fifth transistor T5, a sixth transistor T6, and a seventh transistor T7, and a second plate of a first Scan signal line Scan1, a second Scan signal line Scan2, an enable signal line Emit, and a storage capacitor Cst is disposed on the bottom metal wiring layer 33; the first reference signal line Ref1, the second reference signal line Ref2, and the first plate of the storage capacitor Cst are disposed on the middle metal wiring layer 34; the Data signal line Data and the first power signal line PVDD are disposed on the first metal wiring layer 32, and the different layers can be electrically connected through vias. In which, the driving circuit structure of 1 OLED is exemplarily shown in fig. 21, and an insulating layer between layers is omitted, 35 is an anode output terminal of the light emitting element 51, and 35 is electrically connected to the first electrode layer 51 a.

Specifically, taking 7T1C as an example, when there is a leakage current in the threshold compensation transistor T4, the potential of the N1 node in the driving circuit is easily raised, which results in a decrease in the driving voltage of the light emitting element 51, and further, a decrease in the light emission luminance, which causes color shift after color mixing of the light emitted from the light emitting element 51.

Based on this, as shown in fig. 3-4 and fig. 15-19, the orthographic projection of the grating structure 41 on the substrate 20 and the orthographic projection of the threshold compensation transistor T4 on the substrate 20 are at least partially overlapped, so as to block the external light incident above the threshold compensation transistor T4, and avoid the light leakage of the threshold compensation transistor T4 to the greatest extent.

In other embodiments, for example, circuit structures such as 2T1C, 4T1C, 7T2C, 8T1C, 8T2C, etc., a grating structure is additionally arranged at least above a transistor that is prone to leakage current, so that the color shift problem caused by light leakage current is reduced to the greatest extent, and normal display of the display panel is ensured.

Based on the same inventive concept, the embodiment of the invention also provides a display device. Fig. 22 is a top view of a display device according to an embodiment of the present invention, and as shown in fig. 22, the display device includes any one of the display panels provided in the foregoing embodiments. Illustratively, as shown in fig. 22, the display device 300 includes a display panel 200. Therefore, the display device also has the advantages of the display panel in the above embodiment, and the same points can be understood by referring to the explanation of the display panel, and the description thereof will not be repeated.

The display device 300 provided in the embodiment of the present invention may be a mobile phone as shown in fig. 22, or any electronic product with a display function, including but not limited to the following categories: television, notebook computer, desktop display, tablet computer, digital camera, smart bracelet, smart glasses, vehicle-mounted display, industrial control equipment, medical display screen, touch interactive terminal, etc., which is not particularly limited by the embodiment of the invention.

Note that the above is only a preferred embodiment of the present invention and the technical principle applied. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, while the invention has been described in connection with the above embodiments, the invention is not limited to the embodiments, but may be embodied in many other equivalent forms without departing from the spirit or scope of the invention, which is set forth in the following claims.

Claims

1. The display panel is characterized by comprising a substrate, and a pixel circuit layer and a light-emitting function layer which are sequentially stacked on one side of the substrate, wherein the pixel circuit layer comprises a plurality of pixel circuits, and the pixel circuits comprise a plurality of thin film transistors;

2. The display panel of claim 1, wherein the orthographic projection of the grating structure on the substrate at least partially overlaps with the orthographic projection of at least a portion of the thin film transistor on the substrate.

3. The display panel according to claim 1, wherein a distance between two adjacent light shielding portions in the first direction is L; in the second direction, the height of the light shielding part is H,

Wherein H is larger than or equal to L, and the second direction is perpendicular to the plane of the substrate.

4. The display panel of claim 1, wherein the grating structure comprises a one-dimensional grating.

5. The display panel of claim 1, wherein the grating structure comprises a two-dimensional grating, the first direction comprising at least a first sub-direction and a second sub-direction that intersect each other;

The light shielding part and the light transmitting part are arranged along a first period along the first sub-direction;

Along the second sub-direction, the light shielding portion and the light transmitting portion are disposed along a second period.

6. The display panel of claim 5, wherein the first period is equal to the second period.

7. The display panel according to claim 5, wherein the light shielding portions of the grating structure have a plurality of polygons densely arranged in a front projection shape of the substrate.

8. The display panel of claim 7, wherein the polygon comprises a regular triangle, a parallelogram, or a regular hexagon.

9. The display panel according to claim 1, wherein a front projection shape of the light shielding portion in the first cross section is a trapezoid, and a bottom side length of the trapezoid on a side close to the light emitting function layer is smaller than a bottom side length of the trapezoid on a side close to the pixel circuit layer;

The first section is parallel to the first direction and perpendicular to the plane of the substrate.

10. The display panel according to claim 1, further comprising a planarization layer between the pixel circuit layer and the light-emitting function layer;

the insulating layer is positioned between the planarization layer and the pixel circuit layer;

or the insulating layer is positioned between the planarization layer and the light-emitting functional layer.

11. The display panel according to claim 1, further comprising a planarization layer between the pixel circuit layer and the light-emitting function layer, the insulating layer being multiplexed as the planarization layer.

12. The display panel according to claim 1, further comprising a light shielding metal layer on a side of the thin film transistor close to the light-emitting functional layer;

the orthographic projection of the shading metal layer on the substrate is overlapped with the orthographic projection of at least part of the thin film transistor on the substrate at least partially; the orthographic projection of the shading metal layer on the substrate is overlapped with the orthographic projection of the grating structure on the substrate at least partially.

13. The display panel according to claim 12, wherein the light-emitting functional layer includes a plurality of light-emitting elements including a first electrode layer, a light-emitting layer, and a second electrode layer which are sequentially provided in a direction away from the substrate; the pixel circuit layer comprises at least two metal wiring layers;

The shading metal layer and the first electrode layer and/or the first metal wiring layer are/is the same layer;

The first metal wiring layer is the metal wiring layer closest to the light-emitting functional layer in the pixel circuit layer.

14. The display panel according to claim 13, wherein the first electrode layer is electrically connected to one electrode of the thin film transistor through a via hole of the insulating layer.

15. The display panel according to claim 1, wherein the thin film transistor includes a driving transistor and a threshold compensation transistor;

The first end of the driving transistor is electrically connected with the first end of the threshold compensation transistor, and the control end of the driving transistor is electrically connected with the second end of the threshold compensation transistor; the threshold compensation transistor is used for performing threshold compensation on the driving transistor;

The orthographic projection of the grating structure on the substrate is overlapped with the orthographic projection of the threshold compensation transistor on the substrate at least partially.

16. The display panel according to claim 1, wherein the light shielding portion is formed of a doped nano carbon black material in the insulating layer.

17. A display device comprising the display panel according to any one of claims 1 to 16.