WO2023246379A1

WO2023246379A1 - Display substrate and manufacturing method therefor, and display device

Info

Publication number: WO2023246379A1
Application number: PCT/CN2023/094516
Authority: WO
Inventors: 张智辉; 韩城; 高昊; 吴启晓; 李旭
Original assignee: 京东方科技集团股份有限公司
Priority date: 2022-06-20
Filing date: 2023-05-16
Publication date: 2023-12-28
Also published as: CN115241235A

Abstract

A display substrate and a manufacturing method therefor, and a display device. The display substrate comprises a base substrate (10), a display structure layer (20) provided on the base substrate (10), a light conversion layer (30) provided on the side of the display structure layer (20) distant from the base substrate (10), and a light processing layer (50) provided on the side of the light conversion layer (30) distant from the base substrate (10); the light conversion layer (30) at least comprises a red quantum dot layer, a green quantum dot layer and a light-transmitting layer; the light processing layer (50) comprises a plurality of light processing structures for improving the light exit efficiency and a covering layer (52) provided on the side of the light processing structures distant from the base substrate (10); the orthographic projections of the light processing structures on the base substrate (10) at least partially overlap the orthographic projection of the red quantum dot layer on the base substrate (10); the orthographic projections of the light processing structures on the base substrate (10) at least partially overlap the orthographic projection of the green quantum dot layer on the base substrate (10); the refractive index of the light processing structures is greater than the refractive index of the covering layer (52).

Description

Display substrate and preparation method thereof, display device

This application claims priority to the Chinese patent application filed with the China Patent Office on June 20, 2022, with the application number 202210699592.5 and the invention title "Display Substrate and Preparation Method and Display Device", and its content should be understood as being incorporated by reference. are incorporated into this application.

Technical field

Embodiments of the present disclosure relate to, but are not limited to, the field of display technology, and in particular, to a display substrate, a preparation method thereof, and a display device.

Background technique

Organic Light Emitting Diode (OLED) is an active light-emitting display device. It has the advantages of self-illumination, wide viewing angle, high contrast, low power consumption, extremely high response speed, thinness, flexibility and low cost. It has become the current Mainstream products in the display field.

There is a problem of white light color deviation in display devices using OLED+quantum-dot (QD) materials.

Contents of the invention

The following is an overview of the topics described in detail in this article. This summary is not intended to limit the scope of the claims.

Embodiments of the present disclosure provide a display substrate, a preparation method thereof, and a display device to solve the white light color cast problem of a display device using OLED+QD.

In a first aspect, an embodiment of the present disclosure provides a display substrate, including: a substrate, a display structure layer provided on the substrate, a light conversion layer provided on a side of the display structure layer away from the substrate, and a light conversion layer provided on the side of the display structure layer away from the substrate. The light conversion layer is a light treatment layer on the side away from the substrate; the light conversion layer at least includes a red quantum dot layer, a green quantum dot layer and a light-transmitting layer; the light treatment layer includes a plurality of light treatments that improve light extraction efficiency. structure and a covering layer disposed on the side of the light processing structure away from the substrate, the orthographic projection of the light processing structure on the substrate at least partially intersects the orthographic projection of the red quantum dot layer on the substrate Overlapping, the orthographic projection of the light processing structure on the substrate at least partially overlaps the orthographic projection of the green quantum dot layer on the substrate, and the refractive index of the light processing structure is greater than the refractive index of the covering layer Rate.

In an exemplary embodiment, the light processing structure includes a first light processing structure, and the orthographic projection of the first light processing structure on the substrate includes the orthographic projection of the red quantum dot layer on the substrate, The orthographic projection of the first light processing structure on the substrate includes the orthographic projection of the green quantum dot layer on the substrate.

In an exemplary embodiment, the first light processing structure provided on the red quantum dot layer and the first light processing structure provided on the green quantum dot layer are spaced apart.

In an exemplary embodiment, the first light processing structure provided on the red quantum dot layer and the first light processing structure provided on the green quantum dot layer are an integral structure connected to each other.

In an exemplary embodiment, in a plane perpendicular to the substrate, the cross-sectional shape of the first light processing structure is a trapezoid, the length of the upper base of the trapezoid is G1, the length of the lower base is E1, and the height is F1. , the size relationship of the trapezoid satisfies: 0.65 micron<(F1/((E1-G1)/2))<0.99 micron.

In an exemplary embodiment, the light conversion layer further includes a first black matrix, the first black matrix is disposed between the red quantum dot layer, the green quantum dot layer and the light-transmitting layer; the light processing structure includes a first black matrix. Two light processing structures, the second light processing structure is disposed on the side of the light conversion layer away from the substrate, the second light processing structure is on the base The orthographic projection of the first black matrix on the substrate at least partially overlaps; the orthographic projection of the second light processing structure on the substrate and the orthographic projection of the light-transmitting layer on the substrate There is no overlap in projections.

In an exemplary embodiment, in a plane perpendicular to the substrate, the cross-sectional shape of the second light processing structure is a trapezoid, the length of the upper base of the trapezoid is G2, the length of the lower base is E2, and the height is F2. , the geometric size relationship of the trapezoid satisfies: 0.766 micron<(F2/((E2-G2)/2))<0.939 micron.

In an exemplary embodiment, the light conversion layer further includes a first black matrix, the first black matrix is disposed between the red quantum dot layer, the green quantum dot layer and the light-transmitting layer; the light processing structure includes a first black matrix. A light processing structure and a second light processing structure, the orthographic projection of the first light processing structure on the substrate includes the orthographic projection of the red quantum dot layer and the green quantum dot layer on the substrate, so The orthographic projection of the second light processing structure on the substrate at least partially overlaps with the orthographic projection of the first black matrix on the substrate, and the orthographic projection of the second light processing structure on the substrate overlaps with the orthographic projection of the first black matrix on the substrate. There is no overlap in the orthographic projection of the light-transmitting layer on the substrate.

In an exemplary embodiment, the first light processing structure is located on a side of the second light processing structure away from the substrate, and the refractive index of the second light processing structure is smaller than the refraction of the first light processing structure. Rate.

In an exemplary embodiment, the refractive index of the first light processing structure is set to be greater than or equal to 1.75 and less than or equal to 1.85.

In an exemplary embodiment, the refractive index of the second light processing structure is set to be greater than or equal to 1.42 and less than or equal to 1.53.

In an exemplary embodiment, the display structure layer includes a driving circuit layer, a light-emitting structure layer and a packaging structure layer that are sequentially stacked on the substrate; wherein the light-emitting structure layer at least includes a pixel definition layer, and the pixel A pixel opening is provided on the definition layer; the packaging structure layer includes a plurality of third light processing structures that improve light extraction efficiency, and the orthographic projection of the third light processing structure on the substrate includes the pixel opening on the substrate. orthographic projection on.

In an exemplary embodiment, in a plane perpendicular to the substrate, the cross-sectional shape of the third light processing structure is a trapezoid, the length of the upper base of the trapezoid is G3, the length of the lower base is E3, and the height is F3. , the geometric size relationship of the trapezoid satisfies: 0.75 micron<(F3/((E3-G3)/2))<0.9 micron.

In an exemplary embodiment, the refractive index of the third light processing structure is set to be greater than or equal to 1.7 and less than or equal to 1.8.

In an exemplary embodiment, in a plane perpendicular to the substrate, the length of the pixel opening is C, and the size relationship between the third light processing structure and the pixel opening satisfies: C≤G3<E3<C+ 8 microns.

In an exemplary embodiment, the orthographic projection of the quantum dot layer on the substrate includes the orthographic projection of the pixel opening on the substrate, and the orthographic projection of the quantum dot layer on the substrate is consistent with the orthographic projection of the quantum dot layer on the substrate. The distance between adjacent sides of the orthographic projection of the pixel opening on the substrate is less than or equal to 8 microns.

In an exemplary embodiment, there is a pixel dam between adjacent pixel openings. In a plane perpendicular to the substrate, the length of the orthographic projection of the pixel dam on the substrate is A, and the red quantum dot layer The cross-sectional length is Dr, the cross-sectional length of the green quantum dot layer is Dg, the cross-sectional length of the first black matrix located between the red quantum dot layer and the green quantum dot layer is Db, Dr/2+Dg/2+ Db≤A.

In a second aspect, embodiments of the present disclosure provide a display device, including the display substrate as described above.

In a third aspect, embodiments of the present disclosure provide a method for preparing a display substrate, which includes: forming a display structure layer on a substrate; forming a light conversion layer on a side of the display structure layer away from the substrate. The layer at least includes a red quantum dot layer, a green quantum dot layer and a light-transmitting layer; a light processing layer is formed on the side of the light conversion layer away from the substrate, and the light processing layer includes a plurality of light processing structures that improve light extraction efficiency. and a covering layer disposed on the side of the light processing structure away from the substrate, the orthographic projection of the light processing structure on the substrate at least partially overlaps the orthographic projection of the red quantum dot layer on the substrate , the orthographic projection of the light processing structure on the substrate and the green quantum dot layer Orthographic projections on the substrate at least partially overlap, and the refractive index of the light processing structure is greater than the refractive index of the cover layer.

Other aspects will be apparent after reading and understanding the drawings and detailed description.

Figure overview

The drawings are used to provide an understanding of the technical solution of the present disclosure and constitute a part of the specification. They are used to explain the technical solution of the present disclosure together with the embodiments of the present disclosure and do not constitute a limitation of the technical solution of the present disclosure.

Figure 1 is a schematic structural diagram of an electronic device;

Figure 2 is an equivalent circuit schematic diagram of a pixel driving circuit;

Figure 3 is a schematic plan view of a display substrate according to the present disclosure;

4A is a schematic cross-sectional view of a display substrate in an exemplary embodiment of the present disclosure;

FIG. 4B is a schematic diagram of the dimensions of the first light processing structure in an exemplary embodiment of the present disclosure;

Figure 5 is a schematic cross-sectional view of a display substrate in another exemplary embodiment of the present disclosure;

Figure 6 is a schematic cross-sectional view of a display substrate in yet another exemplary embodiment of the present disclosure;

7A is a schematic cross-sectional view of a display substrate in yet another exemplary embodiment of the present disclosure;

7B is a schematic diagram of the dimensions of the second light processing structure in an exemplary embodiment of the present disclosure;

Figure 8 is a schematic cross-sectional view of a display substrate in yet another exemplary embodiment of the present disclosure;

9A is a schematic cross-sectional view of a display substrate in yet another exemplary embodiment of the present disclosure;

FIG. 9B is a schematic diagram of the dimensions of a third light processing structure in an exemplary embodiment of the present disclosure;

Figure 10 is a schematic diagram of the size of the pixel definition layer in an exemplary embodiment of the present disclosure;

Figure 11 is a top view of the pixel opening and the red quantum dot layer in an exemplary embodiment of the present disclosure;

Figure 12 shows the brightness and angle relationship curves between OLED devices and quantum dot materials of different colors;

Figure 13 shows the relationship between the brightness and angle of the blue light-emitting device, the light conversion layer and the ideal state;

Figure 14 is a relationship curve between brightness and angle of the display substrate of Figure 8 (provided with a third light processing structure) and the display substrate in the embodiment shown in Figure 9A;

Figure 15 shows the white light color deviation curve before and after structural adjustment;

16 to 21 are schematic diagrams of a process of preparing a display substrate in an exemplary embodiment.

Elaborate

The embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. Note that embodiments may be implemented in many different forms. It is understood by those of ordinary skill in the art that the manner and content may be transformed into various forms without departing from the spirit and scope of the present disclosure. Therefore, the present disclosure should not be construed as being limited only to the contents described in the following embodiments. The embodiments and features in the embodiments of the present disclosure may be arbitrarily combined with each other unless there is any conflict.

The scale of the drawings in this disclosure can be used as a reference in actual processes, but is not limited thereto. For example: the width-to-length ratio of the channel, the thickness and spacing of each film layer, and the width and spacing of each signal line can be adjusted according to actual needs. The number of pixels in the display substrate and the number of sub-pixels in each pixel are not limited to the numbers shown in the figures. The figures described in the present disclosure are only structural schematic diagrams, and one mode of the present disclosure is not limited to the figures. The shape or numerical value shown in the figure.

Ordinal numbers such as "first", "second" and "third" in this specification are provided to avoid confusion of constituent elements and are not intended to limit the quantity.

In this manual, the terms "middle", "upper", "lower", "front", "back", "vertical", "horizontal", "top", "bottom", "inner" and "outer" are used. The use of words and phrases indicating orientation or positional relationship to describe the positional relationship of constituent elements with reference to the drawings is only for the convenience of describing this specification and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation or be in a specific manner. orientation construction and operation and therefore should not be construed as limitations of the present disclosure. The positional relationship of the constituent elements can be appropriately changed depending on the direction in which each constituent element is described. Therefore, they are not limited to the words and phrases described in the specification, and may be appropriately replaced according to circumstances.

In this manual, unless otherwise expressly stated and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, or an electrical connection; it can be a direct connection, an indirect connection through an intermediate piece, or an internal connection between two elements. For those of ordinary skill in the art, the meanings of the above terms in this disclosure can be understood according to the circumstances.

In this specification, a transistor refers to an element including at least three terminals: a gate electrode, a drain electrode, and a source electrode. The transistor has a channel region between a drain electrode (drain electrode terminal, drain region, or drain electrode) and a source electrode (source electrode terminal, source region, or source electrode), and current can flow through the drain electrode, channel region, and source electrode . In this specification, the channel region refers to a region through which current mainly flows.

In this specification, the first electrode may be a drain electrode and the second electrode may be a source electrode, or the first electrode may be a source electrode and the second electrode may be a drain electrode. When transistors with opposite polarities are used or when the direction of current changes during circuit operation, the functions of the "source electrode" and the "drain electrode" may be interchanged with each other. Therefore, in this specification, "source electrode" and "drain electrode" can be interchanged with each other, and "source terminal" and "drain terminal" can be interchanged with each other.

In this specification, "electrical connection" includes a case where constituent elements are connected together through an element having some electrical effect. There is no particular limitation on the "element having some electrical function" as long as it can transmit electrical signals between connected components. Examples of "elements having some electrical function" include not only electrodes and wiring, but also switching elements such as transistors, resistors, inductors, capacitors, and other elements with various functions.

In this specification, "parallel" refers to a state in which the angle formed by two straight lines is -10° or more and 10° or less. Therefore, it also includes a state in which the angle is -5° or more and 5° or less. In addition, "vertical" refers to a state where the angle formed by two straight lines is 80° or more and 100° or less, and therefore includes an angle of 85° or more and 95° or less.

In this specification, "film" and "layer" may be interchanged. For example, "conductive layer" may sometimes be replaced by "conductive film." Similarly, "insulating film" may sometimes be replaced by "insulating layer".

The triangles, rectangles, trapezoids, pentagons or hexagons in this specification are not strictly speaking. They can be approximate triangles, rectangles, trapezoids, pentagons or hexagons, etc. There may be some small deformations caused by tolerances. There can be leading angles, arc edges, deformations, etc.

The word “approximately” in this disclosure refers to a value that does not strictly limit the limit and allows for process and measurement errors.

Figure 1 is a schematic structural diagram of an electronic device. As shown in Figure 1, the electronic device may include a timing controller, a data signal driver, a scanning signal driver, a luminescence signal driver, and a pixel array. The timing controller may be connected to the data signal driver, the scanning signal driver, and the luminescence signal driver. The data signal driver It can be connected to multiple data signal lines (D1 to Dn), the scan signal driver can be connected to multiple scan signal lines (S1 to Sm), and the light emitting signal driver can be connected to multiple light emitting signal lines (E1 to Eo). The pixel array may include a plurality of sub-pixels Pxij, i and j may be natural numbers, and at least one sub-pixel Pxij may include a circuit unit and a light-emitting device connected to the circuit unit. The circuit unit may include a pixel driving circuit, and the pixel driving circuit is connected to a scanning signal line, The data signal line and the light-emitting signal line are connected. In an exemplary embodiment, the timing controller may change the gray scale appropriate to the specifications of the data signal driver. Values and control signals are supplied to the data signal driver. A clock signal, a scan start signal, etc. suitable for the specifications of the scan signal driver can be supplied to the scan signal driver. A clock signal, emission stop signal, etc. suitable for the specifications of the light emitting signal driver can be supplied to the scan signal driver. etc. are provided to the light-emitting signal driver. The data signal driver may generate data voltages to be provided to the data signal lines D1, D2, D3, . . . and Dn using the grayscale values and control signals received from the timing controller. For example, the data signal driver may sample the grayscale value using a clock signal and apply a data voltage corresponding to the grayscale value to the data signal lines D1 to Dn in units of pixel rows, where n may be a natural number. The scan signal driver may generate scan signals to be supplied to the scan signal lines S1, S2, S3, . . . and Sm by receiving a clock signal, a scan start signal, and the like from the timing controller. For example, the scan signal driver may sequentially supply scan signals having on-level pulses to the scan signal lines S1 to Sm. For example, the scan signal driver may be configured in the form of a shift register, and may generate the scan signal in a manner that sequentially transmits a scan start signal provided in the form of an on-level pulse to a next-stage circuit under the control of a clock signal , m can be a natural number. The light-emitting signal driver may generate emission signals to be provided to the light-emitting signal lines E1, E2, E3, . . . and Eo by receiving a clock signal, an emission stop signal, or the like from the timing controller. For example, the light-emitting signal driver may sequentially provide emission signals with off-level pulses to the light-emitting signal lines E1 to Eo. For example, the light-emitting signal driver may be configured in the form of a shift register, and may generate the emission signal in a manner that sequentially transmits an emission stop signal provided in the form of a cut-off level pulse to a next-stage circuit under the control of a clock signal, o Can be a natural number.

Figure 2 is an equivalent circuit schematic diagram of a pixel driving circuit. In exemplary embodiments, the pixel driving circuit may be a 3T1C, 4T1C, 5T1C, 5T2C, 6T1C or 7T1C structure. As shown in Figure 2, the pixel driving circuit may include 7 transistors (transistors T1 to seventh transistors T7), 1 storage capacitor C, the pixel driving circuit and 7 signal lines (data signal line D, first scanning signal line S1 , the second scanning signal line S2, the light-emitting signal line E, the initial signal line INIT, the first power supply line VDD and the second power supply line VSS) are connected.

In an exemplary embodiment, the pixel driving circuit may include a first node N1, a second node N2, and a third node N3. The first node N1 may be connected to the first pole of the third transistor T3, the second pole of the fourth transistor T4 and the second pole of the fifth transistor T5, and the second node N2 may be connected to the second pole of the first transistor T1. , the first electrode of the second transistor T2 and the control electrode of the third transistor T3 are connected to the second end of the storage capacitor C. The third node N3 can be connected to the second electrode of the second transistor T2 and the second electrode of the third transistor T3. is connected to the first pole of the sixth transistor T6.

In an exemplary embodiment, the first end of the storage capacitor C is connected to the first power line VDD, and the second end of the storage capacitor C is connected to the second node N2, that is, the second end of the storage capacitor C is connected to the third transistor T3. Control pole connection.

The control electrode of the first transistor T1 is connected to the second scanning signal line S2, the first electrode of the first transistor T1 is connected to the initial signal line INIT, and the second electrode of the first transistor T1 is connected to the second node N2. When the on-level scanning signal is applied to the second scanning signal line S2, the first transistor T1 transmits the initializing voltage to the control electrode of the third transistor T3 to initialize the charge amount of the control electrode of the third transistor T3.

The control electrode of the second transistor T2 is connected to the first scanning signal line S1, the first electrode of the second transistor T2 is connected to the second node N2, and the second electrode of the second transistor T2 is connected to the third node N3. When the on-level scanning signal is applied to the first scanning signal line S1, the second transistor T2 connects the control electrode of the third transistor T3 to the second electrode.

The control electrode of the third transistor T3 is connected to the second node N2, that is, the control electrode of the third transistor T3 is connected to the second end of the storage capacitor C, and the first electrode of the third transistor T3 is connected to the first node N1. The second pole of T3 is connected to the third node N3. The third transistor T3 may be called a driving transistor, and the third transistor T3 determines the amount of the driving current flowing between the first power supply line VDD and the second power supply line VSS according to the potential difference between its control electrode and the first electrode.

The control electrode of the fourth transistor T4 is connected to the first scanning signal line S1, the first electrode of the fourth transistor T4 is connected to the data signal line D, and the second electrode of the fourth transistor T4 is connected to the first node N1. The fourth transistor T4 can be called When the on-level scan signal is applied to the first scan signal line S1, the fourth transistor T4 causes the data voltage of the data signal line D to be input to the pixel drive circuit.

The control electrode of the fifth transistor T5 is connected to the light-emitting signal line E, the first electrode of the fifth transistor T5 is connected to the first power supply line VDD, and the second electrode of the fifth transistor T5 is connected to the first node N1. The control electrode of the sixth transistor T6 is connected to the light-emitting signal line E, the first electrode of the sixth transistor T6 is connected to the third node N3, and the second electrode of the sixth transistor T6 is connected to the first electrode of the light-emitting device. The fifth transistor T5 and the sixth transistor T6 may be called light emitting transistors. When the on-level light-emitting signal is applied to the light-emitting signal line E, the fifth and sixth transistors T5 and T6 cause the light-emitting device to emit light by forming a driving current path between the first power supply line VDD and the second power supply line VSS.

The control electrode of the seventh transistor T7 is connected to the second scanning signal line S2, the first electrode of the seventh transistor T7 is connected to the initial signal line INIT, and the second electrode of the seventh transistor T7 is connected to the first electrode of the light-emitting device. When the on-level scan signal is applied to the second scan signal line S2, the seventh transistor T7 transmits the initializing voltage to the first pole of the light-emitting device, so that the amount of charge accumulated in the first pole of the light-emitting device is initialized or released to emit light. The amount of charge accumulated in the first pole of the device.

In an exemplary embodiment, the light-emitting device may be an OLED including a stacked first electrode (anode), an organic light-emitting layer, and a second electrode (cathode), or may be a QLED including a stacked first electrode (anode) , quantum dot light-emitting layer and second electrode (cathode).

In an exemplary embodiment, the second pole of the light-emitting device is connected to the second power line VSS, the signal of the second power line VSS is a low-level signal, and the signal of the first power line VDD continuously provides a high-level signal.

In an exemplary embodiment, the transistors T1 to T7 may be P-type transistors, or may be N-type transistors. Using the same type of transistors in the pixel drive circuit can simplify the process flow, reduce the process difficulty of the display panel, and improve the product yield. In some possible implementations, the first to seventh transistors T1 to T7 may include P-type transistors and N-type transistors.

In an exemplary embodiment, the first to seventh transistors T1 to T7 may employ low-temperature polysilicon thin film transistors, or may employ oxide thin film transistors, or may employ low-temperature polysilicon thin film transistors and oxide thin film transistors. The active layer of low-temperature polysilicon thin film transistors uses low temperature polysilicon (LTPS), and the active layer of oxide thin film transistors uses oxide semiconductor (Oxide). Low-temperature polysilicon thin film transistors have the advantages of high mobility and fast charging, and oxide thin film transistors have the advantages of low leakage current. Low-temperature polysilicon thin film transistors and oxide thin film transistors are integrated on a display substrate to form low-temperature polycrystalline oxide (Low Temperature Polycrystalline Oxide (LTPO for short) display substrate can take advantage of the advantages of both to achieve low-frequency driving, reduce power consumption, and improve display quality.

In an exemplary embodiment, the light-emitting device may be an organic electroluminescent diode (OLED) including a stacked first electrode (anode), an organic light-emitting layer, and a second electrode (cathode).

In an exemplary implementation, taking the seven transistors in the pixel driving circuit shown in Figure 2 as all P-type transistors as an example, the working process of the pixel driving circuit may include:

The first phase A1 is called the reset phase. The signal of the second scanning signal line S2 is a low-level signal, and the signals of the first scanning signal line S1 and the light-emitting signal line E are high-level signals. The signal of the second scanning signal line S2 is a low-level signal, causing the first transistor T1 and the seventh transistor T7 to be turned on. The first transistor T1 is turned on so that the initial voltage of the initial signal line INIT is provided to the second node N2, which initializes (resets) the storage capacitor C and clears the original data voltage in the storage capacitor. The seventh transistor T7 is turned on so that the initial voltage of the initial signal line INIT is provided to the first pole of the OLED, initializing (resetting) the first pole of the OLED, clearing its internal pre-stored voltage, completing the initialization, and ensuring that the OLED does not emit light. The signals of the first scanning signal line S1 and the light-emitting signal line E are high-level signals, causing the second transistor T2, the fourth transistor T4, the fifth transistor T5 and the sixth transistor T6 to turn off.

The second stage A2 is called the data writing stage or the threshold compensation stage. The signal of the first scanning signal line S1 is a low-level signal, the signals of the second scanning signal line S2 and the light-emitting signal line E are high-level signals, and the data The signal line D outputs the data voltage. At this stage, since the second terminal of the storage capacitor C is at a low level, the third transistor T3 is turned on. The signal of the first scanning signal line S1 is a low-level signal, causing the second transistor T2 and the fourth transistor T4 to be turned on. The second transistor T2 and the fourth transistor T4 are turned on so that the data voltage output by the data signal line D is provided to the second transistor through the first node N1, the turned-on third transistor T3, the third node N3, and the turned-on second transistor T2. Node N2, and the difference between the data voltage output by the data signal line D and the threshold voltage of the third transistor T3 is charged into the storage capacitor C. The voltage at the second end (second node N2) of the storage capacitor C is Vd-|Vth| , Vd is the data voltage output by the data signal line D, and Vth is the threshold voltage of the third transistor T3. The signal of the second scanning signal line S2 is a high-level signal, causing the first transistor T1 and the seventh transistor T7 to be turned off. The signal of the light-emitting signal line E is a high-level signal, causing the fifth transistor T5 and the sixth transistor T6 to be turned off.

The third stage A3 is called the light-emitting stage. The signal of the light-emitting signal line E is a low-level signal, and the signals of the first scanning signal line S1 and the second scanning signal line S2 are high-level signals. The signal of the light-emitting signal line E is a low-level signal, causing the fifth transistor T5 and the sixth transistor T6 to be turned on. The power supply voltage output by the first power supply line VDD passes through the turned-on fifth transistor T5, the third transistor T3 and the sixth transistor T6. The transistor T6 provides a driving voltage to the first pole of the OLED to drive the OLED to emit light.

During the driving process of the pixel driving circuit, the driving current flowing through the third transistor T3 (driving transistor) is determined by the voltage difference between its gate electrode and the first electrode. Since the voltage of the second node N2 is Vdata-|Vth|, the driving current of the third transistor T3 is:
I=K*(Vgs-Vth)2=K*[(Vdd-Vd+|Vth|)-Vth]2=K*(Vdd-Vd)2

Among them, I is the driving current flowing through the third transistor T3, that is, the driving current that drives the OLED, K is a constant, Vgs is the voltage difference between the gate electrode and the first electrode of the third transistor T3, and Vth is the third transistor T3. For the threshold voltage of T3, Vd is the data voltage output by the data signal line D, and Vdd is the power supply voltage output by the first power supply line VDD.

The line width of the luminescence spectrum of quantum dot materials is usually less than 20nm, which can ensure a wider display color gamut and present a more layered and delicate image quality effect. As an inorganic material, quantum dot materials also have a longer service life. , can be prepared based on inkjet printing, spin coating and other processes, which can reduce the high cost caused by the evaporation process. In some technologies, the OLED+QD luminescence form is used in the display device, and a blue monochromatic backlight is used to excite the red quantum dot (RQD) material and the green quantum dot (GQD) material to achieve the emission of white light.

Through research, the inventor of the present application found that in a display device using OLED+QD, as the viewing angle changes, there is a difference in the brightness attenuation of red light and green light and the brightness attenuation of blue light. This difference in brightness causes the display device to have a white light color deviation. Due to the Lambertian emission characteristics of the quantum dot material itself, light will be emitted in all directions when emitting light. The brightness attenuation of GQD and RQD changes with the viewing angle is very small, while the brightness attenuation of the light emitted by the blue light backlight changes with the viewing angle to a large extent. , this uneven brightness attenuation causes the display device to have a white light color cast. Moreover, the overall light extraction efficiency of this display device is not high, which affects the user experience.

FIG. 3 is a schematic plan view of a display substrate according to the present disclosure. As shown in FIG. 3 , the display substrate may include a plurality of pixel units P arranged in a matrix. At least one of the plurality of pixel units P includes a first sub-pixel P1 that emits light of a first color, a third sub-pixel that emits light of a second color. The second sub-pixel P2 and the third sub-pixel P3 that emit light of the third color, the first sub-pixel P1, the second sub-pixel P2 and the third sub-pixel P3 all include a pixel driving circuit and a light-emitting device. The pixel driving circuits in the first sub-pixel P1, the second sub-pixel P2 and the third sub-pixel P3 are individually connected to the scanning signal line, the data signal line and the light-emitting signal line, and the pixel driving circuit is configured to connect the scanning signal line and the light-emitting signal line. Under the control of the data signal line, the data voltage transmitted by the data signal line is received, and a corresponding current is output to the light-emitting device. The light-emitting devices in the first sub-pixel P1, the second sub-pixel P2 and the third sub-pixel P3 are respectively connected to the pixel driving circuit of the corresponding sub-pixel to generate The optical device is configured to emit light with corresponding brightness in response to the current output by the pixel driving circuit of the sub-pixel.

In an exemplary embodiment, the pixel unit P may include red (R) sub-pixels, green (G) sub-pixels, and blue (B) sub-pixels. In exemplary embodiments, the shape of the sub-pixels in the pixel unit may be rectangular, rhombus, pentagon or hexagon. The three sub-pixels can be arranged horizontally, vertically or vertically, or they can be arranged in Real RGB, SRGB or diamond-like arrangements. This disclosure is not limited here. In an exemplary embodiment, a blue light-emitting device may be provided in the pixel unit P, a light-transmitting layer may be provided correspondingly on the side of the first sub-pixel P1 away from the substrate, and a corresponding light-transmitting layer may be provided on the side of the second sub-pixel P2 away from the substrate. For the green quantum dot layer, a red quantum dot layer can be set correspondingly on the side of the third sub-pixel P3 away from the substrate. The light emitted by the blue light-emitting device corresponds to the first sub-pixel after passing through the quantum dot layer and the light-transmitting layer of different colors. The area P1 can emit blue light, the area corresponding to the second sub-pixel P2 can emit green light, and the area corresponding to the third sub-pixel P3 can emit red light. The emission colors of the first sub-pixel P1, the second sub-pixel P2 and the third sub-pixel P3 can be set as needed, and the present disclosure does not limit this.

Embodiments of the present disclosure provide a display substrate, including: a substrate, a display structure layer provided on the substrate, a light conversion layer provided on a side of the display structure layer away from the substrate, and a light conversion layer provided on the side of the display structure layer away from the substrate. The light processing layer on the side away from the substrate; the light conversion layer at least includes a red quantum dot layer, a green quantum dot layer and a light-transmitting layer; the light processing layer includes a plurality of light processing structures that improve light extraction efficiency and is arranged on The light processing structure is away from the covering layer on the side of the substrate, and the orthographic projection of the light processing structure on the substrate at least partially overlaps with the orthographic projection of the red quantum dot layer on the substrate, and the An orthographic projection of the light processing structure on the substrate at least partially overlaps an orthographic projection of the green quantum dot layer on the substrate, and the refractive index of the light processing structure is greater than the refractive index of the cover layer.

The display substrate proposed in the embodiment of the present disclosure disposes a light processing layer on the side of the light conversion layer away from the substrate. The light processing layer includes a plurality of light processing structures that improve light extraction efficiency and a covering layer disposed on the side of the light processing structure away from the substrate. , the refractive index of the light processing structure is greater than the refractive index of the covering layer, the orthographic projection of the light processing structure on the substrate at least partially overlaps with the orthographic projection of the red quantum dot layer on the substrate, and the orthographic projection of the light processing structure on the substrate overlaps with the green Orthographic projections of the quantum dot layers onto the substrate at least partially overlap. Improving the light extraction efficiency of the red quantum dot layer and the green quantum dot layer through the light processing structure can increase the degree of attenuation of the light brightness of the red quantum dot layer and the green quantum dot layer as the viewing angle changes, solving the problem of white light in display devices using OLED+QD Color cast problem.

In an exemplary embodiment, the light conversion layer further includes a first black matrix, the first black matrix is disposed between the red quantum dot layer, the green quantum dot layer and the light-transmitting layer; the light processing structure includes a first black matrix. Two light processing structures, the second light processing structure is disposed on the side of the light conversion layer away from the substrate, and the orthographic projection of the second light processing structure on the substrate is in line with the first black matrix. The orthographic projection on the substrate at least partially overlaps; the orthographic projection of the second light processing structure on the substrate does not overlap with the orthographic projection of the light-transmitting layer on the substrate.

In an exemplary embodiment, in a plane perpendicular to the substrate, the cross-sectional shape of the second light processing structure is Trapezoidal, the length of the upper bottom of the trapezoid is G2, the length of the lower bottom is E2, and the height is F2. The geometric size relationship of the trapezoid satisfies: 0.766 microns < (F2/((E2-G2)/2)) <0.939 Micron.

The light processing structure may include only the first light processing structure, or the light processing structure may include only the second light processing structure, or the light processing structure may include the first light processing structure and the second light processing structure. In the case where the light processing structure only includes the first light processing structure, the light from the red quantum dot layer or the green quantum dot layer can be refracted after being incident on the first light processing structure, causing the light from the red quantum dot layer to move toward the red color. The center of the quantum dot layer is deflected, and the light from the green quantum dot layer is deflected to the center of the green quantum dot layer, thereby improving the light extraction efficiency. In the case where the light processing structure only includes the second light processing structure, the light from the red quantum dot layer can be reflected to the center of the red quantum dot layer after being incident on the surface of the second light processing structure, and the light from the green quantum dot layer can be reflected after being incident on the surface of the second light processing structure. After reaching the surface of the second light treatment structure, it can be reflected to the center of the green quantum dot layer, thereby improving the light extraction efficiency. In the case where the light processing structure includes a first light processing structure and a second light processing structure, the first light processing structure may be located on a side of the second light processing structure away from the substrate, and the first light processing structure and the second light processing structure may Quantum dot layers corresponding to different colors and the first black matrix are arranged, and the refractive index of the second light processing structure can be smaller than the refractive index of the first light processing structure. The position and refraction of the first light processing structure and the second light processing structure Under the efficiency design, after the light from the red quantum dot layer or the green quantum dot layer is incident on the surface of the second light processing structure, total reflection can occur at the interface between the second light processing structure and the first light processing structure, so that the light from the second light processing structure can be completely reflected. The light from the red quantum dot layer is deflected to the center of the red quantum dot layer, and the light from the green quantum dot layer is deflected to the center of the green quantum dot layer, thereby improving the light extraction efficiency.

In an exemplary embodiment, the orthographic projection of the quantum dot layer on the substrate includes the orthographic projection of the pixel opening on the substrate, and the orthographic projection of the quantum dot layer on the substrate is consistent with the orthographic projection of the quantum dot layer on the substrate. Front projection of pixel openings on the substrate The distance between adjacent edges of the shadow is less than or equal to 8 microns.

FIG. 4A is a schematic cross-sectional view of the display substrate in an exemplary embodiment of the present disclosure, taking the A-A direction shown in FIG. 3 , illustrating the structure of three sub-pixels. As shown in FIG. 4A , on a plane perpendicular to the display substrate, the display substrate provided by the embodiment of the present disclosure may include a display structure layer 20 disposed on the substrate 10 , and a light conversion device disposed on the side of the display structure layer 20 away from the substrate 10 Layer 30 is a light processing layer 50 disposed on the side of the light conversion layer 30 away from the substrate 10 .

In an exemplary embodiment, the display structure layer 20 may include a driving circuit layer, a light emitting structure layer, and a packaging structure layer stacked in sequence. The driving circuit layer may include a plurality of transistors and storage capacitors constituting a pixel driving circuit. The light-emitting structure layer may include a pixel definition layer and a light-emitting device. The pixel definition layer may include a plurality of pixel openings. The pixel openings form a light-emitting area. Between adjacent light-emitting areas are pixel dams. The light-emitting device may include an anode, an organic light-emitting layer and a cathode. The light-emitting device may be configured as a blue light-emitting device. The packaging structure layer may include a stacked first sub-layer, a second sub-layer and a third sub-layer. The first sub-layer and the third sub-layer may be made of inorganic materials, and the second sub-layer may be made of organic materials.

In an exemplary embodiment, the light conversion layer 30 may include at least a plurality of first black matrices 31 and a plurality of quantum dot layers 32 . A plurality of first black matrices 31 and a plurality of quantum dot layers 32 may be disposed on the side of the display structure layer 20 away from the substrate 10 , and the plurality of first black matrices 31 may be disposed at intervals between adjacent first black matrices 31 To form light-transmitting openings, multiple quantum dot layers 32 may be spaced apart and may be provided in multiple light-transmitting openings. For example, a single quantum dot layer 32 may be provided in a single light-transmitting opening to form a space separated by the first black matrix 31 . In an open quantum dot layer array, the first black matrix 31 is located between adjacent quantum dot layers 32 .

In an exemplary embodiment, the display structure layer 20 may be provided with a blue light-emitting device, and the plurality of quantum dot layers 32 may include a red quantum dot layer that emits red light, a green quantum dot layer that emits green light, and a light-transmitting layer. The layer is at least transparent to blue light. The red quantum dot layer, the green quantum dot layer and the light-transmitting layer can be respectively arranged corresponding to the blue light-emitting device in the display structure layer 20. The red quantum dot layer can be located in the area where the red sub-pixel (third sub-pixel P3) is located. The quantum dot layer may be located in the area where the green sub-pixel (second sub-pixel P2) is located, and the light-transmitting layer may be located in the area where the blue sub-pixel (first sub-pixel P1) is located. The light emitted by the blue light-emitting device excites the red quantum dot layer and emits red light. The light emitted by the blue light-emitting device excites the green quantum dot layer and emits green light. The light emitted by the blue light-emitting device remains blue light after passing through the light-transmitting layer. Thus, the emitted red light, green light and blue light can be used for image display.

In an exemplary embodiment, the light processing layer 50 may include a plurality of first light processing structures 51 disposed on a side of the light conversion layer 30 away from the substrate 10 and a covering layer disposed on a side of the first light processing structures 51 away from the substrate 10 52. The plurality of first light processing structures 51 can be disposed on the side of the red quantum dot layer and the green quantum dot layer away from the substrate 10 . The positions of the plurality of first light processing structures 51 can be in line with the multiple red quantum dot layers and the plurality of green quantum dot layers. The positions of the point layers correspond one to one. The covering layer 52 may be disposed on a side of the plurality of first light processing structures 51 away from the substrate 10 , and the covering layer 52 may cover the plurality of first light processing structures 51 .

In an exemplary embodiment, the surface of the covering layer 52 on the side away from the substrate 10 may be a planarized surface.

In an exemplary embodiment, the orthographic projection of the first light processing structure 51 on the substrate 10 at least partially overlaps with the orthographic projection of the corresponding red quantum dot layer on the substrate 10 , and the orthographic projection of the first light processing structure 51 on the substrate 10 The orthographic projection at least partially overlaps the orthographic projection of the corresponding green quantum dot layer on the substrate 10 .

In an exemplary embodiment, the orthographic projection of the first light processing structure 51 on the substrate 10 may include an orthographic projection of the corresponding red quantum dot layer on the substrate 10 , and the orthographic projection of the first light processing structure 51 on the substrate 10 may Contains the orthographic projection of the corresponding green quantum dot layer on the substrate 10 .

In an exemplary embodiment, the orthographic projection of the first light processing structure 51 on the substrate 10 and the orthographic projection of the corresponding red quantum dot layer on the substrate 10 may substantially coincide with the orthographic projection of the first light processing structure 51 on the substrate 10 . The orthographic projection and the orthographic projection of the corresponding green quantum dot layer on the substrate 10 may substantially coincide. In this disclosure, "substantially coincident" means that the limits are not strictly limited, some small deformations caused by tolerances can be allowed, differences such as lead angles, arc edges and deformations can exist, and values within the range of process and measurement errors are allowed.

In an exemplary embodiment, the orthographic projection of the first light processing structure 51 on the substrate 10 may overlap with the orthographic projection of the first black matrix 31 on the substrate 10 .

In an exemplary embodiment, the light emitted by the red quantum dot layer is deflected toward the center of the red quantum dot layer after passing through the first light processing structure 51 , and the light emitted by the green quantum dot layer is deflected toward the center after passing through the first light processing structure 51 . The direction deflection at the center of the green quantum dot layer can improve the light extraction efficiency of the sub-pixels. In an exemplary embodiment, the center of the red quantum dot layer may be the geometric center of the red quantum dot layer, and the center of the green quantum dot layer may be the geometric center of the green quantum dot layer. In an exemplary embodiment, the shape of the first light processing structure 51 can be set according to the actual pixel topography or process requirements. On a plane parallel to the display substrate, the shape of the first light processing structure 51 can be any one of the following or Various shapes: triangle, rectangle, pentagon, hexagon, circle and ellipse. In a plane perpendicular to the base, the cross-sectional shape of the first light processing structure 51 may include a trapezoid, an inverted trapezoid or a mushroom shape (T-shape). ), etc., this disclosure does not limit this.

In an exemplary embodiment, the first refractive index n51 of the first light processing structure 51 may be greater than the second refractive index n52 of the covering layer 52. According to the refraction law n51*Sinθi1=n52*Sinθo1, it can be seen that light is incident on the covering layer The first incident angle θi1 of 52 is smaller than the first refraction angle θo1 entering the covering layer 52, that is, relative to the incident light, the light from the red quantum dot layer can be deflected toward the center of the red quantum dot layer after entering the covering layer 52, and the light from the green quantum dot layer can be deflected toward the center of the red quantum dot layer. The light from the quantum dot layer can be deflected toward the center of the green quantum dot layer after entering the covering layer 52 . The greater the difference between the first refractive index n51 and the second refractive index n52, the greater the deflection of light entering the covering layer 52 toward the center of the red quantum dot layer or the center of the green quantum dot layer.

In an exemplary embodiment, the first refractive index n51 of the first light processing structure 51 may be set to be greater than or equal to 1.75 and less than or equal to 1.85. 4B is a schematic dimensional view of the first light processing structure in an exemplary embodiment of the present disclosure. As shown in FIG. 4A and FIG. 4B , in a plane perpendicular to the substrate, the cross-sectional shape of the first light processing structure 51 may be a trapezoid. The length of the upper base of the trapezoid is G1, the length of the lower base is E1, and the height is F1. The geometric dimension relationship of the trapezoid can be 0.65＜(F1/((E1-G1)/2))＜0.99, and the unit of the number in the formula is micron. In an exemplary embodiment, in a plane perpendicular to the substrate, the cross-sectional length of the quantum dot layer 32 may be denoted as D, the cross-sectional length of the red quantum dot layer is Dr, and the cross-sectional length of the green quantum dot layer is Dg. As shown in FIG. 4A , the cross-sectional length D of the quantum dot layer 32 may be the size of the side of the quantum dot layer 32 parallel to the substrate in a plane perpendicular to the substrate, and the length G1 of the upper base of the first light processing structure 51 may be Setting it to be greater than or equal to the cross-sectional length D of the corresponding quantum dot layer 32 can ensure that more light from the red quantum dot layer or the green quantum dot layer is incident on the first light processing structure 51, making the light emitted by the light conversion layer more emitted. Concentration increases the degree of attenuation of the brightness of red and green light as the angle changes, and helps improve the overall light extraction efficiency. In other embodiments, the upper and lower length G1 of the first light processing structure 51 can be set to be smaller than the cross-sectional length D of the corresponding quantum dot layer 32, which helps to better control the relationship between brightness attenuation and angle, so as to reduce Small white light color cast. In practical applications, the relationship between the upper and lower length of the first light processing structure 51 and the corresponding cross-sectional length Dr of the red quantum dot layer, and the relationship between the upper and lower length of the first light processing structure 51 and the corresponding green quantum dot layer can be set as needed. The present disclosure does not limit the relationship between the cross-sectional length Dg.

In an exemplary embodiment, the second refractive index of the covering layer 52 may be set to be greater than or equal to 1.4 and less than or equal to 1.55. On a plane perpendicular to the substrate, the thickness of the covering layer 52 is H, and the thickness H may be the distance between the surface of the covering layer 52 away from the substrate 10 and the surface of the covering layer 52 close to the substrate 10 . The thickness of the covering layer 52 may be set according to the height F1 of the first light processing structure 51, which is not limited by the present disclosure.

In exemplary embodiments, the side walls of the first light processing structure 51 may be polygonal lines, arc lines, wavy lines, etc., and the disclosure is not limited thereto.

FIG. 5 is a schematic cross-sectional view of the display substrate in another exemplary embodiment of the present disclosure, taking the A-A direction shown in FIG. 3 , illustrating the structure of three sub-pixels. The structural layer 20, the light conversion layer 30 and the light processing layer 50 shown in Figure 5 can be referred to the description of Figure 4A and will not be described again here. As shown in FIG. 5 , in an exemplary embodiment, a flat layer 40 may be provided between the display structure layer 20 and the light processing layer 50 . The flat layer 40 may cover the first black matrix 31 and the plurality of quantum dot layers 32 . The surface of the planarization layer 40 on the side away from the substrate 10 may be a planarized surface. In an exemplary embodiment, the material of the flat layer 40 may be optical glue or an inorganic material, which is not limited by the present disclosure.

In an exemplary embodiment, as shown in FIG. 5 , a color filter layer 60 may be disposed on a side of the light processing layer 50 away from the substrate 10 . The color filter layer 60 may include at least a plurality of second black matrices 61 and a plurality of filter layers 62 . A plurality of second black matrices 61 and a plurality of filter layers 62 may be disposed on a side of the light processing layer 50 away from the substrate 10 , and a plurality of second black matrices 61 may be disposed at intervals between adjacent second black matrices 61 To form a light-transmitting opening, multiple filter layers 62 may be spaced apart and may be provided in multiple light-transmitting openings. For example, a single filter layer 62 may be provided in a single light-transmitting opening, forming a layer separated by a second black matrix 61 . In an open filter layer array, the second black matrix 61 is located between adjacent filter layers 62 .

In an exemplary embodiment, the plurality of filter layers 62 may include a red filter layer that transmits red light, a blue filter layer that transmits blue light, and a green filter layer that transmits green light. The red filter layer The layer may be located in the area where the red sub-pixel (the third sub-pixel P3) is located, the green filter layer may be located in the area where the green sub-pixel (the second sub-pixel P2) is located, and the blue filter layer may be located in the blue sub-pixel (the first sub-pixel P2). The area where pixel P1) is located.

In an exemplary embodiment, as shown in FIG. 5 , the module layer 70 may be disposed on a side of the color filter layer 60 away from the substrate 10 .

In the display substrate provided by the exemplary embodiment of the present disclosure, the light processing layer 50 including the first light processing structure 51 and the covering layer 52 is disposed on the side of the light conversion layer 30 away from the substrate 10. The first light processing structure 51 and the red quantum The dot layer and the green quantum dot layer are arranged correspondingly, and the first refractive index n51 of the first light processing structure 51 is greater than the second refractive index n52 of the covering layer 52. Refraction is used to cause the light emitted by the red quantum dot layer to move toward the center of the red quantum dot layer. The light emitted by the green quantum dot layer is deflected in the direction of the center of the green quantum dot layer, which can effectively improve the light extraction efficiency of the sub-pixels, increase the light emission color gamut, reduce the white light color cast, and improve the display quality. Moreover, the display substrate with the structure shown in FIG. 4A or FIG. 5 has a simple preparation process and lower production cost. The thickness of the covering layer 52 can be set to a smaller value, which is beneficial to realizing flexible bending display.

FIG. 6 is a schematic cross-sectional view of the display substrate in yet another exemplary embodiment of the present disclosure. It is a cross-sectional view along the A-A direction shown in FIG. 3 , illustrating the structure of three sub-pixels. As shown in FIG. 6 , on a plane perpendicular to the display substrate, the display substrate provided by the embodiment of the present disclosure may include a display structure layer 20 disposed on the substrate 10 , and a light conversion device disposed on the side of the display structure layer 20 away from the substrate 10 Layer 30 is a light processing layer 50 disposed on the side of the light conversion layer 30 away from the substrate 10 .

In an exemplary embodiment, the structures of the display structure layer 20 , the light conversion layer 30 and the light processing layer 50 in this exemplary embodiment are basically the same as those of the embodiment shown in FIG. 4A , except that they are disposed on the red quantum dot layer. The first light processing structure 51 and the first light processing structure 51 disposed on the green quantum dot layer are an integral structure connected to each other.

In an exemplary embodiment, a plurality of first light processing structures 51 may be disposed on a side of the red quantum dot layer and the green quantum dot layer away from the substrate 10 , and the positions of the first light processing structures 51 may be consistent with the red quantum dot layer and the green quantum dot layer. The positions of the quantum dot layers are set accordingly.

In an exemplary embodiment, the orthographic projection of the first light processing structure 51 on the substrate 10 at least partially overlaps the orthographic projections of the corresponding red and green quantum dot layers on the substrate 10 .

In an exemplary embodiment, the orthographic projection of the first light processing structure 51 on the substrate 10 may include a corresponding red color. Orthographic projection of the quantum dot layer and the green quantum dot layer on the substrate 10 .

In an exemplary embodiment, the orthographic projection of the first light processing structure 51 on the substrate 10 corresponds to the corresponding red quantum dot layer, the green quantum dot layer, and the first black quantum dot layer located between the red quantum dot layer and the green quantum dot layer. The orthographic projections of the matrices onto the substrate 10 may substantially coincide.

In an exemplary embodiment, the light emitted by the red quantum dot layer is deflected toward the center of the red quantum dot layer after passing through the first light processing structure 51 , and the light emitted by the green quantum dot layer is deflected toward the center after passing through the first light processing structure 51 . The direction deflection of the center of the green quantum dot layer can improve the light extraction efficiency of the sub-pixels and increase the attenuation of the light brightness of the light conversion layer as the angle changes. In an exemplary embodiment, the center of the red quantum dot layer may be the geometric center of the red quantum dot layer, and the center of the green quantum dot layer may be the geometric center of the green quantum dot layer. In an exemplary embodiment, the shape of the first light processing structure 51 can be set according to the actual pixel topography or process requirements. In a plane parallel to the substrate, the shape of the first light processing structure 51 can be any one or more of the following: Types: triangle, rectangle, pentagon, hexagon, circle and ellipse. In a plane perpendicular to the base, the cross-sectional shape of the first light processing structure 51 may include a trapezoid, an inverted trapezoid or a mushroom shape (T-shape) etc., this disclosure does not limit this.

In an exemplary embodiment, the first refractive index n51 of the first light processing structure 51 may be greater than the second refractive index n52 of the covering layer 52 . The direction of the arrow in FIG. 6 indicates that the light emitted by the light conversion layer passes through the first light processing structure. The principle analysis of the deflection after 51 can be found in the description of Figure 4A and will not be described again here.

In an exemplary embodiment, the first refractive index n51 of the first light processing structure 51 may be greater than or equal to 1.75 and less than or equal to 1.85. In a plane perpendicular to the substrate, the cross-sectional shape of the first light processing structure 51 may be a trapezoid. The length of the upper base of the trapezoid is G1, the length of the lower base is E1, and the height is F1. The geometric dimension relationship of the trapezoid may be 0.65. <(F1/((E1-G1)/2))<0.99. In practical applications, the shape and size of the first light processing structure 51 can be set as needed, and this disclosure does not limit this.

In an exemplary embodiment, the flat layer 40, the color filter layer 60 and the module layer 70 may also be provided in the display substrate with the structure shown in FIG. 6. Please refer to the relevant description of FIG. 5, which will not be described again here.

In the display substrate provided by the exemplary embodiment of the present disclosure, the light processing layer 50 including the first light processing structure 51 and the covering layer 52 is provided on the side of the light conversion layer 30 away from the substrate 10, and the third light processing layer 50 is provided on the red quantum dot layer. A light processing structure 51 and the first light processing structure 51 disposed on the green quantum dot layer are an integral structure connected to each other, and the first refractive index n51 of the first light processing structure 51 is greater than the second refractive index n52 of the covering layer 52 , using refraction to deflect the emitted light of the red quantum dot layer toward the center of the red quantum dot layer, and deflecting the emitted light of the green quantum dot layer toward the center of the green quantum dot layer, which can effectively improve the light extraction efficiency of the sub-pixels and improve the light color. It can also reduce the white light color cast and improve the display quality. Moreover, the display substrate with the structure shown in FIG. 6 simplifies the preparation process of the first light processing structure 51, which helps to improve the production yield and reduce the production cost. Compared with the structure in Figure 4A or Figure 5, the light exit path of the red quantum dot layer in the structure shown in Figure 6 is reduced by a trapezoidal slope, and the light exit path of the green quantum dot layer is reduced by a trapezoidal slope, allowing for more flexibility. Adjust the relationship between brightness attenuation and angle. The thickness H of the cover layer 52 can be set to a smaller value to facilitate flexible bending display.

FIG. 7A is a schematic cross-sectional view of the display substrate in yet another exemplary embodiment of the present disclosure. It is a cross-sectional view along the A-A direction shown in FIG. 3 , illustrating the structure of three sub-pixels. As shown in FIG. 7A , on a plane perpendicular to the display substrate, the display substrate provided by the embodiment of the present disclosure may include a display structure layer 20 disposed on the substrate 10 , and a light conversion device disposed on the side of the display structure layer 20 away from the substrate 10 Layer 30 is a light processing layer 50 disposed on the side of the light conversion layer 30 away from the substrate 10 .

In an exemplary embodiment, the structures of the display structure layer 20 and the light conversion layer 30 in this exemplary embodiment are basically the same as those of the embodiment shown in FIG. 4A , except that the light processing layer 50 further includes a second light processing structure 53 .

In an exemplary embodiment, as shown in FIG. 7A , the light processing layer 50 may include a plurality of second light processing structures 53 disposed on a side of the light conversion layer 30 away from the substrate 10 , and the second light processing structures 53 are disposed on a side away from the substrate. 10 more on one side A first light processing structure 51 and a covering layer 52 disposed on a side of the first light processing structure 51 away from the substrate 10 . The positions of the plurality of second light processing structures 53 may be set in one-to-one correspondence with the positions of the plurality of first black matrices 31 . The positions of the plurality of first light processing structures 51 can correspond to the positions of the plurality of red quantum dot layers and green quantum dot layers. The covering layer 52 may be disposed on a side of the plurality of first light processing structures 51 away from the substrate 10 , and the covering layer 52 may cover the plurality of first light processing structures 51 and the plurality of second light processing structures 53 .

In an exemplary embodiment, the orthographic projection of the second light processing structure 53 on the substrate 10 may overlap with the corresponding orthographic projection of the first black matrix 31 on the substrate 10 .

In an exemplary embodiment, the orthographic projection of the second light processing structure 53 on the substrate 10 may include the corresponding orthographic projection of the first black matrix 31 on the substrate 10 .

In an exemplary embodiment, the orthographic projection of the second light processing structure 53 on the substrate 10 at least partially overlaps with the orthographic projection of the red quantum dot layer on the substrate 10 , and the orthographic projection of the second light processing structure 53 on the substrate 10 At least partially overlaps with the orthographic projection of the green quantum dot layer on the substrate 10 .

In an exemplary embodiment, the orthographic projection of the second light processing structure 53 on the substrate 10 does not overlap with the orthographic projection of the light-transmitting layer on the substrate 10 .

In an exemplary embodiment, the orthographic projection of the first light processing structure 51 on the substrate 10 and the orthographic projection of the corresponding red quantum dot layer on the substrate 10 may substantially coincide with the orthographic projection of the first light processing structure 51 on the substrate 10 . The orthographic projection and the orthographic projection of the corresponding green quantum dot layer on the substrate 10 may substantially coincide.

In an exemplary embodiment, the light emitted by the red quantum dot layer is deflected toward the center of the red quantum dot layer after passing through the first light processing structure 51 , and the light emitted by the green quantum dot layer is deflected toward the center after passing through the first light processing structure 51 . The direction deflection at the center of the green quantum dot layer can improve the light extraction efficiency of the sub-pixels. In an exemplary embodiment, the center of the red quantum dot layer may be the geometric center of the red quantum dot layer, and the center of the green quantum dot layer may be the geometric center of the green quantum dot layer. In an exemplary embodiment, the shape of the first light processing structure 51 can be set according to the actual pixel topography or process requirements. On a plane parallel to the display substrate, the shape of the first light processing structure 51 can be any one of the following or Various shapes: triangle, rectangle, pentagon, hexagon, circle and ellipse. In a plane perpendicular to the base, the cross-sectional shape of the first light processing structure 51 may include a trapezoid, an inverted trapezoid or a mushroom shape (T-shape). ), etc., this disclosure does not limit this. FIG. 7A illustrates the situation where light is directly emitted from the first light processing structure 51. For this situation, please refer to the description in FIG. 4A and will not be described again.

In an exemplary embodiment, the first refractive index n51 of the first light processing structure 51 may be set to be greater than or equal to 1.75 and less than or equal to 1.85. FIG. 7B is a schematic diagram of the dimensions of the second light processing structure in an exemplary embodiment of the present disclosure. In a plane perpendicular to the substrate, the cross-sectional shape of the first light processing structure 51 may be a trapezoid. The length of the upper base of the trapezoid is G1, the length of the lower base is E1, and the height is F1. The geometric dimension relationship of the trapezoid may be 0.76. <(F1/((E1-G1)/2))<0.984, the unit of the number in the formula is micron. In an exemplary embodiment, in a plane perpendicular to the substrate, the quantum The cross-sectional length of the dot layer 32 can be expressed as D, the cross-sectional length of the red quantum dot layer is Dr, and the cross-sectional length of the green quantum dot layer is Dg. The upper and lower length G1 of the first light processing structure 51 can be set to be greater than or equal to the cross-sectional length D of the corresponding quantum dot layer 32, which can ensure that more light from the red quantum dot layer or the green quantum dot layer is incident on the first light. In the processing structure 51, the light emitted by the light conversion layer is more concentrated, increasing the degree of attenuation of the brightness of red light and green light with angle changes, and helping to improve the overall light extraction efficiency; in other embodiments, the second The top and bottom length G1 of a light processing structure 51 is set to be smaller than the cross-sectional length D of the corresponding quantum dot layer 32, which helps to better control the relationship between brightness attenuation and angle to reduce white light color cast. In practical applications, the relationship between the upper and lower length of the first light processing structure 51 and the corresponding cross-sectional length Dr of the red quantum dot layer or the cross-sectional length Dg of the green quantum dot layer can be set as needed, and this disclosure does not limit this.

In an exemplary embodiment, the first refractive index n51 of the first light processing structure 51 may be greater than the third refractive index n53 of the second light processing structure 53, and the second incident angle θi2>total reflection critical angle β, total reflection critical angle Angle β=arcsin(n53/n51).

In an exemplary embodiment, light is incident on the interface of the first light processing structure 51 and the second light processing structure 53 at the second incident angle θi2. Since the second incident angle θi2 is greater than the total reflection critical angle β, the incident light occurs Total reflection re-enters the first light processing structure 51 at the second reflection angle θo2. The light re-entering the first light processing structure 51 is deflected toward the center of the sub-pixel. The second incident angle θi2 = the second reflection angle θo2.

In an exemplary embodiment, the third refractive index n53 of the second light processing structure 53 may be set to be greater than or equal to 1.42 and less than or equal to 1.53. As shown in FIGS. 7A and 7B , in a plane perpendicular to the substrate, the cross-sectional shape of the second light processing structure 53 may be a trapezoid. The length of the upper base of the trapezoid is G2, the length of the lower base is E2, and the height is F2. The geometric dimension relationship of the trapezoid can be 0.766<(F2/((E2-G2)/2))<0.939. In an exemplary embodiment, there is an overlap between the orthographic projection of the second light processing structure 53 on the substrate 10 and the orthographic projection of the red quantum dot layer on the substrate 10 . The orthographic projection of the second light processing structure 53 on the substrate 10 In the case where there is overlap with the orthographic projection of the green quantum dot layer on the substrate 10, the larger the overlap area between the projections, the faster the brightness attenuation speed changes with the angle. In an exemplary embodiment, there is no overlap between the orthographic projection of the second light processing structure 53 on the substrate 10 and the orthographic projection of the red quantum dot layer on the substrate 10 . In the case where there is no overlap between the projection and the orthographic projection of the green quantum dot layer on the substrate 10, the farther the distance between adjacent boundaries between the projections, the slower the brightness attenuation speed with angle changes. In practical applications, the positional relationship between the orthographic projection of the second light processing structure 53 on the substrate 10 and the red quantum dot layer, and the positional relationship between the orthographic projection of the second light processing structure 53 on the substrate 10 and the green quantum dot layer can be set as needed. The present disclosure does not limit the positional relationship of the orthographic projection on the substrate 10 .

In an exemplary embodiment, the light processing structure may only include the second light processing structure 53, and the light from the red quantum dot layer and the green quantum dot layer can be deflected toward their respective centers under the reflection of the second light processing structure 53, Thereby improving the light extraction efficiency.

In an exemplary embodiment, the second refractive index of the covering layer 52 may be set to be greater than or equal to 1.4 and less than or equal to 1.55. The thickness H of the covering layer 52 can satisfy F1+F2+1<H<F1+F2+1.5, and the unit of the number in the relational expression is micrometer.

In an exemplary embodiment, the flat layer 40, the color filter layer 60 and the module layer 70 may also be provided in the display substrate with the structure shown in FIG. 7A. Please refer to the relevant description of FIG. 5, which will not be described again here.

The display substrate provided by exemplary embodiments of the present disclosure disposes the light processing layer 50 including the second light processing structure 53, the first light processing structure 51 and the covering layer 52 on the side of the light conversion layer 30 away from the substrate 10. The light processing structure 53 is provided correspondingly to the first black matrix 31 , the first light processing structure 51 is provided correspondingly to the red quantum dot layer and the green quantum dot layer, and the first refractive index n51 of the first light processing structure 51 is greater than the first refractive index n51 of the covering layer 52 . Two refractive index n52, the first refractive index n51 of the first light processing structure 51 is greater than the third refractive index n53 of the second light processing structure 53, using refraction and total reflection The radiation deflects the emitted light of the red quantum dot layer toward the center of the red quantum dot layer, and the emitted light of the green quantum dot layer deflects toward the center of the green quantum dot layer, which can effectively improve the light extraction efficiency of the sub-pixels, improve the light emission color gamut, and also It can reduce the color cast of white light and improve the display quality.

FIG. 8 is a schematic cross-sectional view of the display substrate in yet another exemplary embodiment of the present disclosure. It is a cross-sectional view along the A-A direction shown in FIG. 3 , illustrating the structure of three sub-pixels. As shown in FIG. 8 , on a plane perpendicular to the display substrate, the display substrate provided by the embodiment of the present disclosure may include a display structure layer 20 disposed on the substrate 10 , and a light conversion device disposed on the side of the display structure layer 20 away from the substrate 10 Layer 30 is a light processing layer 50 disposed on the side of the light conversion layer 30 away from the substrate 10 .

In an exemplary embodiment, the structures of the display structure layer 20 , the light conversion layer 30 and the light processing layer 50 in this exemplary embodiment are basically the same as those of the embodiment shown in FIG. 7A , except that they are disposed on the red quantum dot layer. The first light processing structure 51 and the first light processing structure 51 disposed on the green quantum dot layer are an integral structure connected to each other.

In an exemplary embodiment, the light emitted by the red quantum dot layer is deflected toward the center of the red quantum dot layer after passing through the first light processing structure 51 , and the light emitted by the green quantum dot layer is deflected toward the center after passing through the first light processing structure 51 . The direction deflection of the center of the green quantum dot layer can improve the light extraction efficiency of the sub-pixels and increase the attenuation speed of the light brightness of the light conversion layer as the angle changes. In an exemplary embodiment, the center of the red quantum dot layer may be the geometric center of the red quantum dot layer, and the center of the green quantum dot layer may be the geometric center of the green quantum dot layer. In an exemplary embodiment, the shape of the first light processing structure 51 can be set according to the actual pixel topography or process requirements. In a plane parallel to the substrate, the shape of the first light processing structure 51 can be any one or more of the following: Types: triangle, rectangle, pentagon, hexagon, circle and ellipse. In a plane perpendicular to the base, the cross-sectional shape of the first light processing structure 51 may include a trapezoid, an inverted trapezoid or a mushroom shape (T-shape) etc., this disclosure does not limit this.

In an exemplary embodiment, the first refractive index n51 of the first light processing structure 51 may be greater than the second refractive index n52 of the covering layer 52 . The direction of the arrow in FIG. 8 illustrates that the light emitted by the light conversion layer passes through the first light processing structure. The principle analysis of the deflection after 51 can be found in the description of Figure 4A and will not be described again here.

In an exemplary embodiment, the first refractive index n51 of the first light processing structure 51 is greater than or equal to 1.75 and less than or equal to 1.85. In a plane perpendicular to the substrate, the cross-sectional shape of the first light processing structure 51 may be a trapezoid. The length of the upper base of the trapezoid is G1, the length of the lower base is E1, and the height is F1. The geometric dimension relationship of the trapezoid may be 0.76. <(F1/((E1-G1)/2))<0.984. In practical applications, the shape and size of the first light processing structure 51 can be set as needed, and this disclosure does not limit this.

In an exemplary embodiment, the flat layer 40, the color filter layer 60 and the module layer 70 may also be provided in the display substrate with the structure shown in Figure 8. Please refer to the relevant description of Figure 5, which will not be described again here.

The display substrate provided by exemplary embodiments of the present disclosure disposes the light processing layer 50 including the second light processing structure 53, the first light processing structure 51 and the covering layer 52 on the side of the light conversion layer 30 away from the substrate 10. The light processing structure 53 is provided correspondingly to the first black matrix 31 , the first light processing structure 51 is provided correspondingly to the red quantum dot layer and the green quantum dot layer, and the first refractive index n51 of the first light processing structure 51 is greater than the first refractive index n51 of the covering layer 52 . The second refractive index n52, the first refractive index n51 of the first light processing structure 51 is greater than the third refractive index n53 of the second light processing structure 53, using refraction and total reflection to make the emitted light of the red quantum dot layer move toward the center of the red quantum dot layer. The light emitted from the green quantum dot layer is deflected in the direction of the center of the green quantum dot layer, which can effectively improve the light extraction efficiency of the sub-pixels, increase the light emission color gamut, reduce the white light color cast, and improve the display quality. Moreover, the display substrate with the structure shown in FIG. 8 simplifies the preparation process of the first light processing structure 51, which helps to improve the production yield and reduce the production cost. Compared with the structure in Figure 7A, the light exit path of the red quantum dot layer in the structure shown in Figure 8 is reduced by a trapezoidal slope, and the light exit path of the green quantum dot layer is reduced by a trapezoidal slope, allowing for more flexible adjustment of brightness attenuation. and changes in angle.

FIG. 9A is a schematic cross-sectional view of the display substrate in yet another exemplary embodiment of the present disclosure. It is a cross-sectional view along the A-A direction shown in FIG. 3 , illustrating the structure of three sub-pixels. As shown in FIG. 9A , on a plane perpendicular to the display substrate, the display substrate provided by the embodiment of the present disclosure may include a display structure layer 20 disposed on the substrate 10 , and a light conversion device disposed on the side of the display structure layer 20 away from the substrate 10 Layer 30 is a light processing layer 50 disposed on the side of the light conversion layer 30 away from the substrate 10 .

In an exemplary embodiment, the structure of the light conversion layer 30 and the light processing layer 50 in this exemplary embodiment is basically the same as that of the embodiment shown in FIG. 7A , except that the display structure layer 20 includes a third light processing structure.

In an exemplary embodiment, the display structure layer 20 includes a driving circuit layer 21 , a light-emitting structure layer located on the side of the driving circuit layer 21 away from the substrate 10 , and an encapsulation structure layer located on the side of the light-emitting structure layer away from the substrate 10 . The driving circuit layer 21 may include a plurality of transistors and storage capacitors constituting a pixel driving circuit. The light-emitting structure layer may include a pixel definition layer 22 and a light-emitting device 23. The pixel definition layer 22 may include a plurality of pixel openings. The pixel openings form a light-emitting area, and between adjacent light-emitting areas are pixel dams. The light-emitting device 23 may include an anode, an organic light-emitting layer and the cathode. The light-emitting device 23 can be a blue light-emitting device. Multiple light-emitting devices 23 can be arranged in one-to-one correspondence with the red quantum dot layer, the green quantum dot layer and the light-transmitting layer. The light-emitting device 23 is schematically illustrated in Figure 9A. The packaging structure layer may include a stacked first sub-layer 24, a second sub-layer 25 and a third sub-layer 26. The first sub-layer 24 and the third sub-layer 26 may be made of inorganic materials, and the second sub-layer 25 may be made of organic materials. Material.

In an exemplary embodiment, the first sub-layer 24 of the packaging structure layer may include a plurality of third light processing structures, and the plurality of third light processing structures may be disposed on a side of the plurality of light emitting devices 23 away from the substrate 10, and a plurality of third light processing structures may be disposed on a side of the plurality of light emitting devices 23 away from the substrate 10. The position of the third light processing structure may correspond to the positions of the plurality of light emitting devices 23 one-to-one. The second sub-layer 25 may be disposed on a side of the plurality of third light processing structures away from the substrate 10 , and the second sub-layer 25 may cover the plurality of third light processing structures. The third sub-layer 26 may be disposed on a side of the second sub-layer 25 away from the substrate 10 , and the third sub-layer 26 may cover the second sub-layer 25 .

In an exemplary embodiment, the orthographic projection of the third light processing structure on the substrate 10 at least partially overlaps the orthographic projection of the corresponding pixel opening on the substrate 10 .

In an exemplary embodiment, the orthographic projection of the third light processing structure on the substrate 10 may include the orthographic projection of the corresponding pixel opening on the substrate 10 .

In an exemplary embodiment, the light emitted by the light-emitting device 23 can be deflected toward the center of the pixel opening after passing through the third light processing structure, allowing more light to illuminate the red quantum dot layer or the green quantum dot layer, which helps Better excitation of quantum dot materials to produce light of corresponding colors can also make the blue light passing through the light-transmitting layer more concentrated and improve the light extraction efficiency. In an exemplary embodiment, the pixel opening center may be the geometric center of the pixel opening. In an exemplary embodiment, the shape of the third light processing structure can be set according to the actual pixel topography or process requirements. In a plane parallel to the substrate, the shape of the third light processing structure can be any one or more of the following: Triangular, rectangular, pentagonal, hexagonal, circular and elliptical, in a plane perpendicular to the base, the cross-sectional shape of the third light processing structure may include a trapezoid Shape, inverted trapezoid or mushroom shape (T-shape), etc., this disclosure does not limit this.

In an exemplary embodiment, the fourth refractive index of the third light processing structure may be greater than the fifth refractive index of the second sub-layer 25 , and the refraction angle of light when incident from the third light processing structure to the second sub-layer 25 is less than The incident angle is such that, relative to the incident light, the light entering the second sub-layer 25 is deflected toward the center of the pixel opening, as shown in FIG. 9A . The greater the difference between the fourth refractive index of the third light processing structure and the fifth refractive index of the second sub-layer 25, the greater the deflection of light entering the second sub-layer 25 toward the center of the pixel opening.

In an exemplary embodiment, the fourth refractive index of the third light processing structure may be set to be greater than or equal to 1.7 and less than or equal to 1.8. FIG. 9B is a schematic diagram of the dimensions of a third light processing structure in an exemplary embodiment of the present disclosure. As shown in FIG. 9A and FIG. 9B , in a plane perpendicular to the substrate, the cross-sectional shape of the third light processing structure may be a trapezoid. The length of the upper base of the trapezoid is G3, the length of the lower base is E3, and the height is F3. The geometric dimension relationship of the trapezoid can be 0.75<(F3/((E3-G3)/2))<0.9.

In an exemplary embodiment, the third refractive index n53 of the second light processing structure 53 may be set to be greater than or equal to 1.42 and less than or equal to 1.53. In a plane perpendicular to the base, the cross-sectional shape of the second light processing structure 53 may be a trapezoid. The length of the upper base of the trapezoid is G2, the length of the lower base is E2, and the height is F2. The geometric size relationship of the trapezoid may be 0.766. <(F2/((E2-G2)/2))<0.939. In an exemplary embodiment, there is an overlap between the orthographic projection of the second light processing structure 53 on the substrate 10 and the orthographic projection of the red quantum dot layer on the substrate 10 . The orthographic projection of the second light processing structure 53 on the substrate 10 In the case where there is overlap with the orthographic projection of the green quantum dot layer on the substrate 10, the larger the overlap area between the projections, the faster the brightness attenuation speed changes with the angle. In an exemplary embodiment, there is no overlap between the orthographic projection of the second light processing structure 53 on the substrate 10 and the orthographic projection of the red quantum dot layer on the substrate 10 . In the case where there is no overlap between the projection and the orthographic projection of the green quantum dot layer on the substrate 10, the farther the distance between adjacent boundaries between the projections, the slower the brightness attenuation speed with angle changes. In practical applications, the positional relationship between the orthographic projection of the second light processing structure 53 on the substrate 10 and the orthographic projection of the red quantum dot layer or the green quantum dot layer on the substrate 10 can be set as needed, and this disclosure does not limit this.

FIG. 10 is a schematic diagram of the dimensions of a pixel definition layer in an exemplary embodiment of the present disclosure. FIG. 11 is a top view of a pixel opening and a red quantum dot layer in an exemplary embodiment of the present disclosure. As shown in FIG. 10 , the pixel definition layer 22 includes a plurality of pixel openings. The pixel openings form light-emitting areas, and pixel dams are formed between adjacent light-emitting areas. On a plane perpendicular to the base, the cross-sectional shape of the pixel dam can be a trapezoid, the length of the bottom of the pixel dam is A, the length of the orthographic projection of the trapezoidal slope of the pixel dam on the base is B, and the length between adjacent pixel dams is The length of the pixel opening is C, that is, the length of the orthographic projection of the pixel dam on the substrate is A. In an exemplary embodiment, the length B of the orthographic projection of the trapezoidal slope surface of the pixel dam on the substrate may be less than or equal to 8 microns. In other embodiments, the length B of the orthogonal projection of the trapezoidal slope surface of the pixel dam on the substrate Can be less than or equal to 5 microns. In an exemplary embodiment, the orthographic projection of the third light processing structure on the substrate may include the orthographic projection of the pixel opening on the substrate, and the size relationship between the third light processing structure and the pixel opening satisfies: C≤G3<E3<C+8 , the unit of the number in the formula is micron, which can allow more light to enter the corresponding quantum dot layer. In an exemplary embodiment, in a plane perpendicular to the substrate, the cross-sectional length of the quantum dot layer 32 may be represented as D, the cross-sectional length of the red quantum dot layer is Dr, the cross-sectional length of the green quantum dot layer is Dg, and the cross-sectional length of the adjacent quantum dot layer 32 is Dg. The first black matrix 31 between the red quantum dot layer and the green quantum dot layer The cross-sectional length is Db. In an exemplary embodiment, Dr/2+Dg/2+Db≤A can be set to ensure that as much light as possible emitted from the slope of the third light processing structure is incident on the corresponding red quantum dot layer or green quantum dot. layer. Taking the red quantum dot layer as an example, as shown in Figure 11, the cross-sectional length of the red quantum dot layer is Dr and the pixel opening length is C. The relationship between the two can be C＜Dr＜16+C, and the unit of the number in the formula is microns, the distance between the orthographic projection of the quantum dot layer 32 on the substrate 10 and the adjacent sides of the orthographic projection of the corresponding pixel opening on the substrate 10 is less than or equal to 8 microns. The relationship between the green quantum dot layer and the light-transmitting layer and the pixel opening length C can be the same as that of the red quantum dot layer.

In an exemplary embodiment, as shown in FIG. 11 , the distance a between adjacent sides of the orthographic projection of the red quantum dot layer on the substrate 10 and the orthographic projection of the corresponding pixel opening on the substrate 10 may be greater than or equal to 5.5 microns. And less than or equal to 9 microns, the relationship between the green quantum dot layer and the light-transmitting layer and the pixel opening length can be the same as that of the red quantum dot layer. In an exemplary embodiment, the orthographic projection of the second light processing structure 53 on the substrate 10 and the orthographic projection of the pixel opening on the substrate 10 may not overlap, and the orthographic projection of the second light processing structure 53 on the substrate 10 does not overlap with that of the pixel opening. The distance between adjacent sides of the orthographic projection of the opening on the substrate 10 may be set to be greater than or equal to 4 micrometers and less than or equal to 6 micrometers.

In an exemplary embodiment, taking the red quantum dot layer as an example, the size relationship between the first light processing structure 51 and the red quantum dot layer also satisfies: Dr<G1<E1<A+C. The relationship between the green quantum dot layer and the light-transmitting layer and the pixel opening length can be the same as that of the red quantum dot layer.

In an exemplary embodiment, the flat layer 40, the color filter layer 60 and the module layer 70 may also be provided in the display substrate with the structure shown in FIG. 9A. Please refer to the relevant description of FIG. 5, which will not be described again here.

The display substrate provided by exemplary embodiments of the present disclosure can effectively improve the light extraction efficiency of sub-pixels by arranging a third light processing structure corresponding to the pixel opening in the display structure layer 20 and using refraction to deflect the emitted light toward the center of the pixel opening. . By arranging the light processing layer 50 including the second light processing structure 53 , the first light processing structure 51 and the covering layer 52 on the side of the light conversion layer 30 away from the substrate 10 , the second light processing structure 53 is arranged corresponding to the first black matrix 31 , the first light processing structure 51 is arranged corresponding to the red quantum dot layer and the green quantum dot layer. The first refractive index n51 of the first light processing structure 51 is greater than the second refractive index n52 of the covering layer 52. The first refractive index n51 is greater than the third refractive index n53 of the second light processing structure 53. Refraction and total reflection are used to deflect the emitted light of the red quantum dot layer toward the center of the red quantum dot layer, and the emitted light of the green quantum dot layer is deflected toward the center of the red quantum dot layer. The deflection of the center direction of the green quantum dot layer can effectively improve the light extraction efficiency of the sub-pixels, increase the light emission color gamut, reduce the white light color cast, and improve the display quality. The third light processing structure, the second light processing structure 53, the first light processing structure 51, the light emitting device and the light conversion layer are arranged to cooperate with each other in position and size, further improving the display quality.

In an exemplary embodiment, the display structure layer 20 of the structure shown in FIG. 9A can also be applied to the structures shown in other embodiments.

In an exemplary embodiment, the display structure layer 20 of the structure shown in FIG. 9A may be used in the display substrate shown in FIG. 4A , and a third light processing structure may be provided in the display structure layer 20 of FIG. 4A . In this case, the size of the first light processing structure 51 can satisfy: G1<E1<A+C. You can set the size relationship between G1 and D as needed.

In an exemplary embodiment, the display structure layer 20 of the structure shown in FIG. 9A may be used in the display substrate shown in FIG. 8 , and a third light processing structure may be provided in the display structure layer 20 of FIG. 8 . In this case, the size of the first light processing structure 51 can satisfy: 2C+A<G1<E1<2A+2C. You can set the size relationship between G1 and D as needed.

The following describes the effect of adjusting the relationship between brightness attenuation and angle according to the embodiment of the present disclosure through the relationship curve between brightness and angle.

Figure 12 shows the brightness and angle relationship curves of OLED devices and quantum dot materials of different colors. Figure 13 shows the relationship between the blue light-emitting device, the light conversion layer and the brightness and angle under ideal conditions. In Figure 12, the abscissa represents angle and the ordinate represents intensity. The three solid lines represent the brightness and angle relationship of the green light-emitting device, the red light-emitting device and the blue light-emitting device in order from top to bottom. Curve, two nearly coincident dotted lines Indicates the brightness and angle relationship curve of red quantum dot material and green quantum dot material. It can be seen from Figure 12 that the curve of the quantum dot material is overall higher than the curve of the light-emitting device. That is, as the angle increases, the brightness attenuation of the quantum dot material is smaller than that of the light-emitting device, and the brightness of the quantum dot material is the lowest. The intensity of the point is still above 0.7, while the intensity of the lowest point of the brightness of the light-emitting device is below 0.3, and there is a large difference between the two. Therefore, directly using a combination of light-emitting devices + quantum dot materials to generate red, green, and blue light in a display substrate will cause a large color shift of white light and poor display effects. In Figure 13, two approximately overlapping dotted lines represent the brightness and angle relationship curves of red quantum dot materials and green quantum dot materials, the solid line in the center represents the ideal brightness and angle relationship curve, and the solid line below represents blue The relationship between brightness and angle of a light-emitting device. In Figure 13, the intensity of the lowest brightness point of the ideal curve is around 0.6. The direction of the arrow indicates that in order to achieve the ideal curve, the brightness and angle relationship curve of the quantum dot material and the brightness and angle relationship curve of the blue light-emitting device need to be closer to the middle. . That is, it is necessary to increase the degree of brightness attenuation of the quantum dot material as the angle changes, and to reduce the degree of brightness attenuation of the blue light-emitting device as the angle changes.

FIG. 14 is a relationship curve between brightness and angle of the display substrate of FIG. 8 (provided with the third light processing structure) and the display substrate in the embodiment shown in FIG. 9A. The upper curve in FIG. 14 represents the relationship between brightness and angle of the display substrate of FIG. 8 provided with the third light processing structure, and the lower curve in FIG. 14 represents the relationship between brightness and angle of the display substrate in the embodiment shown in FIG. 9A curve. The intensity of the lowest brightness point of both curves is around 0.6. It can be seen that the brightness and angle relationship curve of the display substrate in the above embodiment is basically consistent with the ideal brightness and angle relationship curve, which greatly improves the display effect of the display substrate. The display substrates provided in the embodiments of the present disclosure can all achieve ideal brightness and angle relationship curve effects. When there are differences in structural settings, the brightness and angle relationship curves of different display substrates have different smoothness. Taking the curve in Figure 14 as an example, compared to Figure 9A, the first light processing structure in Figure 8 reduces the slope that can change the light path, so the brightness of the display substrate in Figure 8 changes more slowly with the angle. .

Figure 15 shows the white light color deviation curve before and after structural adjustment. As shown in Figure 15, under the 1931 chromaticity coordinate, the white light color shift curve of a display substrate that directly uses a combination of light-emitting devices + quantum dot materials to generate red, green and blue light is Curve 1, and after the embodiment of the present disclosure The white light color shift curve of the display substrate obtained after structural adjustment is curve 2. It can be clearly seen from Figure 15 that after the structural adjustment of the embodiment of the present disclosure, the white light color cast problem of the display substrate has been greatly improved.

An embodiment of the present disclosure also provides a display device, including the display substrate described in any of the above embodiments. The display device may be: an OLED display, a mobile phone, a tablet computer, a television, a monitor, a notebook computer, a digital photo frame, a navigator, or any other product or component with a display function. The embodiments of the present disclosure are not limited thereto.

Embodiments of the present disclosure also provide a method for preparing a display substrate, including: forming a display structure layer on a substrate; forming a light conversion layer on a side of the display structure layer away from the substrate, where the light conversion layer at least includes A red quantum dot layer, a green quantum dot layer and a light-transmitting layer; a light processing layer is formed on the side of the light conversion layer away from the substrate, and the light processing layer includes a plurality of light processing structures that improve light extraction efficiency and is arranged on The light processing structure is away from the covering layer on the side of the substrate, and the orthographic projection of the light processing structure on the substrate at least partially overlaps with the orthographic projection of the red quantum dot layer on the substrate, and the An orthographic projection of the light processing structure on the substrate at least partially overlaps an orthographic projection of the green quantum dot layer on the substrate, and the refractive index of the light processing structure is greater than the refractive index of the cover layer.

The structure of the display substrate of the present disclosure is explained below through an example of a display substrate preparation process. The "patterning process" mentioned in this disclosure includes processes such as depositing film layers, coating photoresist, mask exposure, development, etching, and stripping photoresist. The deposition may be any one or more selected from sputtering, evaporation and chemical vapor deposition, the coating may be any one or more selected from spraying and spin coating, and the etching may be selected from dry etching. and any one or more of wet engraving. "Thin film" refers to a thin film produced by depositing or coating a certain material on a substrate. If the "film" does not require a patterning process during the entire production process, the "film" can also be called a "layer." When the "thin film" requires a patterning process during the entire production process, it is called a "thin film" before the patterning process, and it is called a "layer" after the patterning process. The "layer" after the patterning process contains at least one "pattern". “A and B are set on the same layer” mentioned in this disclosure means that A and B are arranged in the same composition The process is formed simultaneously. "The orthographic projection of A contains the orthographic projection of B" means that the orthographic projection of B falls within the orthographic projection range of A, or the orthographic projection of A covers the orthographic projection of B.

In an exemplary embodiment, the preparation process of the display substrate may include the following steps.

(1) Form the driving circuit layer pattern. In an exemplary embodiment, forming the driving circuit layer pattern may include:

A first insulating film and a semiconductor film are sequentially deposited on the substrate 10, and the semiconductor film is patterned through a patterning process to form a first insulating layer covering the substrate, and a semiconductor layer pattern disposed on the first insulating layer. Each sub-pixel The semiconductor layer pattern may include at least a plurality of active layers.

Subsequently, a second insulating film and a first conductive film are deposited in sequence, and the first conductive film is patterned through a patterning process to form a second insulating layer covering the semiconductor layer pattern, and a first conductive layer disposed on the second insulating layer. Layer pattern, the first conductive layer pattern of each sub-pixel may at least include a plurality of gate electrodes and a first electrode plate.

Subsequently, a third insulating film and a second conductive film are deposited in sequence, and the second conductive film is patterned through a patterning process to form a third insulating layer covering the first conductive layer, and a second insulating layer disposed on the third insulating layer. The conductive layer pattern, and the second conductive layer pattern of each sub-pixel may at least include a second electrode plate, and an orthographic projection of the second electrode plate on the substrate at least partially overlaps an orthographic projection of the first electrode plate on the substrate.

Subsequently, a fourth insulating film is deposited, and the fourth insulating film is patterned through a patterning process to form a fourth insulating layer pattern covering the second conductive layer pattern, and two active via holes are formed on the fourth insulating layer of each sub-pixel. , two active vias expose both ends of the active layer.

Subsequently, a third conductive film is deposited, patterned through a patterning process, and a third conductive layer pattern is formed on the fourth insulating layer. The third conductive layer pattern at least includes: a source electrode located on each sub-pixel and a The drain electrode and the source electrode are connected to the active layer through one of the active via holes, and the drain electrode is connected to the active layer through the other active via hole.

Subsequently, a flat film is coated on the substrate with the aforementioned pattern, and the flat film is patterned through a patterning process to form a flat layer pattern covering the third conductive layer pattern. At least one connection via is formed on the flat layer of each sub-pixel. , the connecting via exposes the surface of the drain electrode.

At this point, the driver circuit layer 21 pattern is prepared, as shown in FIG. 16 . FIG. 16 is a cross-sectional view along the A-A direction shown in FIG. 3 , illustrating the structure of three sub-pixels. In an exemplary embodiment, the driving circuit layer 20 of each sub-pixel may include a plurality of transistors and storage capacitors constituting a pixel driving circuit. In FIG. 16 , only the pixel driving circuit including one transistor 101A and a storage capacitor 101B is taken as an example.

In an exemplary embodiment, the transistor 101A may include an active layer, a gate electrode, a source electrode, and a drain electrode, and the storage capacitor 101B may include a first plate and a second plate. In an exemplary embodiment, the transistor 101A may be a driving transistor in a pixel driving circuit, and the driving transistor may be a thin film transistor (TFT).

In exemplary embodiments, the substrate may be a rigid substrate, or may be a flexible substrate. The rigid substrate can be made of materials such as glass or quartz, and the flexible substrate can be made of materials such as polyimide (PI). The flexible substrate can be a single-layer structure, or it can be a laminated structure composed of an inorganic material layer and a flexible material layer. The present disclosure No limitation is made here.

In an exemplary embodiment, the first insulating layer, the second insulating layer, the third insulating layer and the fourth insulating layer may adopt silicon oxide (SiOx), silicon nitride (SiNx) and silicon oxynitride (SiON). Any one or more, can be single layer, multi-layer or composite layer. The first insulating layer may be called a buffer (Buffer) layer, the second insulating layer and the third insulating layer may be called (GI) layers, and the fourth insulating layer may be called an interlayer insulation (ILD) layer. The first conductive layer, the second conductive layer and the third conductive layer may be made of metal materials, such as any one of silver (Ag), copper (Cu), aluminum (Al), titanium (Ti) and molybdenum (Mo) or More kinds, or alloy materials of the above metals, such as aluminum-neodymium alloy (AlNd) or molybdenum-niobium alloy (MoNb), can be a single-layer structure or a multi-layer composite structure, such as Ti/Al/Ti, etc. The flat layer can be Organic materials such as resin, etc. The semiconductor layer can be made of amorphous indium gallium zinc oxide (a-IGZO), zinc oxynitride (ZnON), indium zinc tin oxide (IZTO), amorphous silicon (a-Si), polycrystalline silicon (p-Si), six Various materials such as thiophene and polythiophene, that is, the disclosure is applicable to transistors manufactured based on oxide Oxide technology, silicon technology, and organic technology, and the disclosure is not limited here.

(2) Form a light-emitting structure layer pattern. In an exemplary embodiment, forming the light emitting structure layer pattern may include:

Deposit a fourth conductive film on the substrate with the foregoing pattern, and pattern the fourth conductive film through a patterning process to form an anode electrode layer pattern. The anode electrode layer pattern of each sub-pixel may at least include an anode 201, and the anode 201 is connected through The via hole is connected to the drain electrode of the transistor 101A.

Subsequently, a pixel definition film is coated on the substrate on which the foregoing pattern is formed, and the pixel definition film is patterned through a patterning process to form a pixel definition layer 22. The pixel definition layer of each sub-pixel is provided with a pixel opening, and the pixels in the pixel opening are The definition film is removed, exposing the surface of anode 201.

Subsequently, on the substrate with the foregoing pattern, an organic light-emitting layer 203 located in each sub-pixel is formed by evaporation or inkjet printing. The organic light-emitting layer 203 is connected to the anode 201 through the pixel opening.

Subsequently, on the substrate with the aforementioned pattern, a cathode 204 pattern is formed by evaporation using an open mask. The cathode 204 with a full-surface structure is connected to the organic light-emitting layer 203, thereby realizing the organic light-emitting layer 203, the anode 201 and the cathode 204. Connection.

At this point, the light-emitting structure layer pattern is prepared, as shown in Figure 17. Figure 17 is a cross-sectional view along the A-A direction shown in Figure 3, illustrating the structure of three sub-pixels.

In an exemplary embodiment, the fourth conductive film may adopt a metal material, a transparent conductive material, or a multi-layer composite structure of a metal material and a transparent conductive material. The metal material may include silver (Ag), copper (Cu), aluminum (Al) , any one or more of titanium (Ti) and molybdenum (Mo), or alloy materials of the above metals, the transparent conductive material can include indium tin oxide (ITO) or indium zinc oxide (IZO), multi-layer composite structure It can be ITO/Al/ITO, etc.

In an exemplary embodiment, the material of the pixel definition film may include polyimide, acrylic, or the like. In an exemplary embodiment, a half-tone mask patterning process may be used to form a spacer column pattern when forming the pixel definition layer pattern. The spacer column may be disposed outside the pixel opening, and the spacer column The pillars are configured to support the fine metal mask in the subsequent evaporation process, which is not limited by the present disclosure.

In an exemplary embodiment, the organic light-emitting layer may include an emitting layer (EML), and any one or more of the following: a hole injection layer (HIL), a hole transport layer (HTL), an electron blocking layer (EBL), Hole blocking layer (HBL), electron transport layer (ETL) and electron injection layer (EIL).

In an exemplary embodiment, the organic light-emitting layer can be prepared in the following manner: first, an open mask (OPM) evaporation process is used or an inkjet printing process is used to sequentially form a hole injection layer and a hole transport layer. layer and an electron blocking layer, forming a common layer of a hole injection layer, a hole transport layer and an electron blocking layer on the display substrate. Then, the evaporation process of Fine Metal Mask (FMM) or the inkjet printing process is used to form different luminescent layers in different sub-pixels. The luminescent layers of adjacent sub-pixels can have a small amount of overlap ( For example, the overlapping portion accounts for less than 10% of the area of the respective light-emitting layer patterns), or may be isolated. The hole blocking layer, electron transport layer and electron injection layer are then sequentially formed using an open mask evaporation process or an inkjet printing process, and the hole blocking layer, electron transport layer and electron injection layer are formed on the display substrate. Common layer.

In an exemplary embodiment, a microcavity adjustment layer may be included in the organic light-emitting layer so that the thickness of the organic light-emitting layer between the cathode and the anode meets the design of the microcavity length. In some exemplary embodiments, a hole transport layer, an electron blocking layer, a hole blocking layer or an electron transport layer can be used as the microcavity adjustment layer, which is not limited by the present disclosure.

In an exemplary embodiment, the light emitting layer may include a host material and a guest doped in the host material. (Dopant) material, the doping ratio of the guest material of the light-emitting layer is 1% to 20%. Within this doping ratio range, on the one hand, the host material of the light-emitting layer can effectively transfer the exciton energy to the guest material of the light-emitting layer to stimulate the guest material of the light-emitting layer to emit light; on the other hand, the host material of the light-emitting layer "dilutes the guest material of the light-emitting layer""It effectively improves the fluorescence quenching caused by the collision between molecules of the guest material in the light-emitting layer and the collision between energy, and improves the luminous efficiency and device life. In exemplary embodiments, the doping ratio refers to the ratio of the mass of the guest material to the mass of the light-emitting layer, that is, the mass percentage. In an exemplary embodiment, the host material and the guest material can be co-evaporated through a multi-source evaporation process, so that the host material and the guest material are evenly dispersed in the light-emitting layer, and the evaporation rate of the guest material can be controlled during the evaporation process. To control the doping ratio, or to control the doping ratio by controlling the evaporation rate ratio of the host material and the guest material. In exemplary embodiments, the thickness of the light emitting layer may be approximately 10 nm to 50 nm.

In exemplary embodiments, the hole injection layer may use inorganic oxides, such as molybdenum oxide, titanium oxide, vanadium oxide, rhenium oxide, ruthenium oxide, chromium oxide, zirconium oxide, and hafnium oxide. , tantalum oxide, silver oxide, tungsten oxide or manganese oxide, or a p-type dopant of a strong electron-withdrawing system and a dopant of a hole transport material can be used, and the thickness of the hole injection layer can be about 5nm to 20nm.

In an exemplary embodiment, the hole transport layer may use a material with a high hole mobility, such as an aromatic amine compound, and its substituent may be carbazole, methylfluorene, or spirofluene. , dibenzothiophene or furan, etc., the thickness of the hole transport layer can be about 40nm to 150nm.

In exemplary embodiments, the hole blocking layer and the electron transport layer may use aromatic heterocyclic compounds, such as benzimidazole derivatives, imidazopyridine derivatives, benziimidazophenanthridine derivatives and other imidazole derivatives; pyrimidine Derivatives, triazine derivatives and other oxazine derivatives; quinoline derivatives, isoquinoline derivatives, phenanthroline derivatives and other compounds containing a nitrogen-containing six-membered ring structure (also including compounds with a phosphine oxide system on the heterocyclic ring) Substituent compounds), etc. In exemplary embodiments, the hole blocking layer may have a thickness of approximately 5 nm to 15 nm, and the electron transport layer may have a thickness of approximately 20 nm to 50 nm.

In exemplary embodiments, the electron injection layer may use alkali metals or metals, such as lithium fluoride (LiF), ytterbium (Yb), magnesium (Mg) or calcium (Ca), or compounds of these alkali metals or metals. etc., the thickness of the electron injection layer may be about 0.5nm to 2nm.

In an exemplary embodiment, the cathode may be made of any one or more of magnesium (Mg), silver (Ag), aluminum (Al), copper (Cu), and lithium (Li), or any one of the above metals. made of one or more alloys.

In some possible exemplary embodiments, the optical coupling layer pattern can be formed after the cathode pattern is formed. The optical coupling layer is disposed on the cathode. The refractive index of the optical coupling layer can be greater than the refractive index of the cathode, which is beneficial to light extraction and increases light extraction. Efficiency, the material of the optical coupling layer can be made of organic materials, or inorganic materials, or organic materials and inorganic materials, and can be a single layer, multi-layer or composite layer, which is not limited by this disclosure.

(3) Form the packaging structure layer pattern. In an exemplary embodiment, forming the encapsulation structure layer pattern may include: first depositing a first encapsulation film using an open mask using a deposition method on the substrate on which the foregoing pattern is formed, and then patterning the first encapsulation film using dry etching. to form a first sub-layer 24 including a third light processing structure. Alternatively, the third optical glue may be coated after depositing the first packaging film, and the third optical glue may be formed into a third light processing structure through a photolithography process. In an exemplary embodiment, the optical glue may be doped to obtain a third optical glue having a fourth refractive index. Then, an open mask is used to print the second packaging material using an inkjet printing process to form the second sub-layer 25 . Then, an open mask is used to deposit a third packaging film using a deposition method to form the third sub-layer 26 .

At this point, the packaging structural layer pattern is prepared, as shown in Figure 18. Figure 18 is a cross-sectional view along the A-A direction shown in Figure 3, illustrating the structure of three sub-pixels.

In an exemplary embodiment, the first sub-layer 24 of the packaging structure layer may include a plurality of third light processing structures, and the plurality of third light processing structures may be disposed on a side of the plurality of light emitting devices 23 away from the substrate 10, and a plurality of third light processing structures may be disposed on a side of the plurality of light emitting devices 23 away from the substrate 10. The position of the third light processing structure may correspond to the positions of the plurality of light emitting devices 23 one-to-one. The second sub-layer 25 may be disposed in a plurality of third light processing On the side of the structure away from the substrate 10, the second sub-layer 25 may cover a plurality of third light processing structures. The third sub-layer 26 may be disposed on a side of the second sub-layer 25 away from the substrate 10 , and the third sub-layer 26 may cover the second sub-layer 25 .

In an exemplary embodiment, the light emitted by the light-emitting device 23 can be deflected toward the center of the pixel opening after passing through the third light processing structure, allowing more light to illuminate the red quantum dot layer or the green quantum dot layer, which helps Better excitation of quantum dot materials to produce light of corresponding colors can also make the blue light passing through the light-transmitting layer more concentrated and improve the light extraction efficiency. In an exemplary embodiment, the pixel opening center may be the geometric center of the pixel opening. In an exemplary embodiment, the shape of the third light processing structure can be set according to the actual pixel topography or process requirements. In a plane parallel to the substrate, the shape of the third light processing structure can be any one or more of the following: Triangular, rectangular, pentagonal, hexagonal, circular and elliptical, in a plane perpendicular to the base, the cross-sectional shape of the third light processing structure may include trapezoid, inverted trapezoid or mushroom shape (T-shape), etc., this There are no restrictions on disclosure.

In an exemplary embodiment, the fourth refractive index of the third light processing structure may be set to be greater than or equal to 1.7 and less than or equal to 1.8. In a plane perpendicular to the substrate, the cross-sectional shape of the third light processing structure may be a trapezoid. The length of the upper base of the trapezoid is G3, the length of the lower base is E3, and the height is F3. The geometric size relationship of the trapezoid may be 0.75< (F3/((E3-G3)/2))<0.9.

In an exemplary embodiment, the first packaging film and the third packaging film may be made of any one or more of silicon oxide (SiOx), silicon nitride (SiNx), and silicon oxynitride (SiON), and may be a single material. Layers, multi-layers or composite layers can ensure that external water and oxygen cannot enter the light-emitting structure layer. The deposition method can be chemical vapor deposition (CVD) or atomic layer deposition (ALD). The second packaging film can be made of organic materials, such as resin, etc., and plays the role of covering each film layer of the display substrate to improve structural stability and flatness.

(4) Patterns of the light conversion layer 30 and the flat layer 40 are formed in sequence.

In an exemplary embodiment, forming the light conversion layer 30 pattern may include: first coating a black matrix film on the substrate on which the foregoing pattern is formed, and patterning the black matrix film through a patterning process to form a first black matrix pattern, The first black matrix pattern may at least include a plurality of first black matrices 31 , and the plurality of first black matrices 31 may be arranged at intervals to form light-transmitting openings between adjacent first black matrices 31 . Subsequently, processes such as spin coating and inkjet printing can be used to form a plurality of red quantum dot layers, green quantum dot layers and light-transmitting layers respectively in the light-transmitting openings formed by the first black matrix 31 . Subsequently, the flat layer 40 is formed. The material of the flat layer 40 may be organic materials such as optical glue, or may be inorganic materials, and this disclosure does not limit this.

At this point, the light conversion layer 30 and the flat layer 40 patterns are prepared, as shown in Figure 19. Figure 19 is a cross-sectional view along the A-A direction shown in Figure 3, illustrating the structure of three sub-pixels.

In an exemplary embodiment, the light conversion layer 30 may include at least a plurality of first black matrices 31 and a plurality of quantum dot layers 32 . A plurality of first black matrices 31 and a plurality of quantum dot layers 32 may be disposed on the side of the display structure layer 20 away from the substrate 10 , and the plurality of first black matrices 31 may be disposed at intervals between adjacent first black matrices 31 Forming light-transmitting openings, multiple quantum The dot layers 32 can be arranged at intervals and can be arranged in multiple light-transmitting openings. For example, a single quantum dot layer 32 can be arranged in a single light-transmitting opening to form an array of quantum dot layers separated by the first black matrix 31. A black matrix 31 is located between adjacent quantum dot layers 32 .

In an exemplary embodiment, the display structure layer 20 may be provided with a blue light-emitting device, and the plurality of quantum dot layers 32 may include a red quantum dot layer that emits red light, a green quantum dot layer that emits green light, and a light-transmitting layer. The layer is at least transparent to blue light. The red quantum dot layer, the green quantum dot layer and the light-transmitting layer respectively correspond to the blue light-emitting device provided in the display structure layer 20. The red quantum dot layer can be located in the area where the red sub-pixel (third sub-pixel P3) is located, and the green quantum dot layer can be located in the area where the red sub-pixel (third sub-pixel P3) is located. The dot layer may be located in the area where the green sub-pixel (second sub-pixel P2) is located, and the light-transmitting layer may be located in the area where the blue sub-pixel (first sub-pixel P1) is located. The light emitted by the blue light-emitting device excites the red quantum dot layer and emits red light. The light emitted by the blue light-emitting device excites the green quantum dot layer and emits green light. The light emitted by the blue light-emitting device remains blue light after passing through the light-transmitting layer. Thus, the emitted red light, green light and blue light can be used for image display.

The pixel definition layer 22 includes a plurality of pixel openings, the pixel openings form light-emitting areas, and pixel dams are formed between adjacent light-emitting areas. On a plane perpendicular to the base, the cross-sectional shape of the pixel dam can be a trapezoid, the length of the bottom of the pixel dam is A, the length of the orthographic projection of the trapezoidal slope of the pixel dam on the base is B, and the length between adjacent pixel dams is The length of the pixel opening is C, that is, the length of the orthographic projection of the pixel dam on the substrate is A. In an exemplary embodiment, the length B of the orthographic projection of the trapezoidal slope surface of the pixel dam on the substrate may be less than or equal to 8 microns. In other embodiments, the length B of the orthogonal projection of the trapezoidal slope surface of the pixel dam on the substrate Can be less than or equal to 5 microns. In an exemplary embodiment, the orthographic projection of the third light processing structure on the substrate may include the orthographic projection of the pixel opening on the substrate, and the size relationship between the third light processing structure and the pixel opening satisfies: C≤G3<E3<C+8 , the unit of the number in the formula is micron, which can allow more light to enter the corresponding quantum dot layer. In an exemplary embodiment, in a plane perpendicular to the substrate, the cross-sectional length of the quantum dot layer 32 may be represented as D, the cross-sectional length of the red quantum dot layer is Dr, the cross-sectional length of the green quantum dot layer is Dg, and the cross-sectional length of the adjacent quantum dot layer 32 is Dg. The cross-sectional length of the first black matrix 31 between the red quantum dot layer and the green quantum dot layer is Db. In an exemplary embodiment, Dr/2+Dg/2+Db≤A can be set to ensure that as much light as possible emitted from the slope of the third light processing structure is incident on the corresponding red quantum dot layer or green quantum dot. layer. Taking the red quantum dot layer as an example, as shown in Figure 11, the cross-sectional length of the red quantum dot layer is Dr and the pixel opening length is C. The relationship between the two can be C＜Dr＜16+C, and the unit of the number in the formula is microns, the distance between the orthographic projection of the quantum dot layer 32 on the substrate 10 and the adjacent sides of the orthographic projection of the corresponding pixel opening on the substrate 10 is less than or equal to 8 microns. The relationship between the green quantum dot layer and the light-transmitting layer and the pixel opening length C can be the same as that of the red quantum dot layer.

(5) Form the light processing layer 50 pattern.

In an exemplary embodiment, forming the pattern of the light processing layer 50 may include: first depositing a second optical film by deposition on the substrate on which the foregoing pattern is formed, and then patterning the second optical film to form a second light processing structure. 53. Alternatively, a second optical glue may be coated on the substrate on which the foregoing pattern is formed, and the second optical glue may be formed into the second light processing structure 53 through a photolithography process. In an exemplary embodiment, doping may be performed in the optical glue to obtain a second optical glue having a third refractive index.

Then, a first optical film is deposited by a deposition method, and then the first optical film is patterned to form a first light processing structure 51 . Alternatively, the first optical glue can be coated on the substrate on which the foregoing pattern is formed, and the first optical glue can be used to form the first light processing structure 51 through a photolithography process. In an exemplary embodiment, doping may be performed in the optical glue to obtain a first optical glue having a first refractive index. A third optical film is then deposited to form a covering layer 52 covering the plurality of first light processing structures 51 .

In an exemplary embodiment, the first optical film, the second optical film and the third optical film may be made of any one or more of silicon oxide (SiOx), silicon nitride (SiNx) and silicon oxynitride (SiON). It can be a single layer, multiple layers or composite layers, and the deposition method can be chemical vapor deposition (CVD) or atomic layer deposition (ALD).

At this point, the pattern of the light processing layer 50 is prepared, as shown in FIG. 20 . FIG. 20 is a cross-sectional view along the A-A direction shown in FIG. 3 , illustrating the structure of three sub-pixels.

In an exemplary embodiment, the light processing layer 50 may include a plurality of second light processing structures 53 disposed on a side of the light conversion layer 30 away from the substrate 10 , and a plurality of second light processing structures 53 disposed on a side of the second light processing structure 53 away from the substrate 10 . The first light processing structure 51 and the covering layer 52 provided on the side of the first light processing structure 51 away from the substrate 10 . The positions of the plurality of second light processing structures 53 may be set in one-to-one correspondence with the positions of the plurality of first black matrices 31 . The positions of the plurality of first light processing structures 51 can correspond to the positions of the plurality of red quantum dot layers and green quantum dot layers. The covering layer 52 may be disposed on a side of the plurality of first light processing structures 51 away from the substrate 10 , and the covering layer 52 may cover the plurality of first light processing structures 51 and the plurality of second light processing structures 53 .

In an exemplary embodiment, the first refractive index n51 of the first light processing structure 51 may be set to be greater than or equal to 1.75 and less than or equal to 1.85. In a plane perpendicular to the substrate, the cross-sectional shape of the first light processing structure 51 may be a trapezoid. The length of the upper base of the trapezoid is G1, the length of the lower base is E1, and the height is F1. The geometric dimension relationship of the trapezoid may be 0.76. <(F1/((E1-G1)/2))<0.984, the unit of the number in the formula is micron. In an exemplary embodiment, in a plane perpendicular to the substrate, the cross-sectional length of the quantum dot layer 32 may be denoted as D, the cross-sectional length of the red quantum dot layer is Dr, and the cross-sectional length of the green quantum dot layer is Dg. The upper and lower length G1 of the first light processing structure 51 can be set to be greater than or equal to the cross-sectional length D of the corresponding quantum dot layer 32, which can ensure that more light from the red quantum dot layer or the green quantum dot layer is incident on the first light. In the processing structure 51, the light emitted by the light conversion layer is more concentrated, increasing the degree of attenuation of the brightness of red light and green light with angle changes, and helping to improve the overall light extraction efficiency; in other embodiments, the second The top and bottom length G1 of a light processing structure 51 is set to be smaller than the cross-sectional length D of the corresponding quantum dot layer 32, which helps to better control the relationship between brightness attenuation and angle to reduce white light color cast. In practical applications, the relationship between the upper and lower length of the first light processing structure 51 and the corresponding cross-sectional length Dr of the red quantum dot layer can be set as needed, and the relationship between the upper and lower length of the first light processing structure 51 and the corresponding green quantum dot layer can be set as needed. The present disclosure does not limit the relationship between the cross-sectional length Dg of the quantum dot layer.

In the exemplary embodiment, the light is incident on the interface of the first light processing structure 51 and the second light processing structure 53 at the second incident angle θi2. Since the second incident angle θi2 is greater than the total reflection critical angle β, the incident light is completely reflected. Reflected, the light re-enters the first light processing structure 51 at the second reflection angle θo2. The light re-entering the first light processing structure 51 is deflected toward the center of the sub-pixel, and the second incident angle θi2 = the second reflection angle θo2.

In an exemplary embodiment, the light processing structure may only include the second light processing structure 53. The light from the red quantum dot layer can be deflected toward the center of the red quantum dot layer under the reflection of the second light processing structure 53. The green quantum dot layer The light from the dot layer can be deflected toward the center of the green quantum dot layer under the reflection of the second light processing structure 53, thereby improving the light extraction efficiency.

The pixel definition layer 22 includes a plurality of pixel openings, the pixel openings form light-emitting areas, and pixel dams are formed between adjacent light-emitting areas. On a plane perpendicular to the base, the cross-sectional shape of the pixel dam can be a trapezoid, the length of the bottom of the pixel dam is A, the length of the orthographic projection of the trapezoidal slope of the pixel dam on the base is B, and the length between adjacent pixel dams is The length of the pixel opening is C, that is, the length of the orthographic projection of the pixel dam on the substrate is A. In an exemplary embodiment, the orthographic projection of the trapezoidal slope of the pixel dam on the substrate The length B of the shadow may be less than or equal to 8 microns. In other embodiments, the length B of the orthographic projection of the trapezoidal slope of the pixel dam on the substrate may be less than or equal to 5 microns. In an exemplary embodiment, the orthographic projection of the third light processing structure on the substrate may include the orthographic projection of the pixel opening on the substrate, and the size relationship between the third light processing structure and the pixel opening satisfies: C≤G3<E3<C+8 , the unit of the number in the formula is micron, which can allow more light to enter the corresponding quantum dot layer. In an exemplary embodiment, in a plane perpendicular to the substrate, the cross-sectional length of the quantum dot layer 32 may be represented as D, the cross-sectional length of the red quantum dot layer is Dr, the cross-sectional length of the green quantum dot layer is Dg, and the cross-sectional length of the adjacent quantum dot layer 32 is Dg. The cross-sectional length of the first black matrix 31 between the red quantum dot layer and the green quantum dot layer is Db. In an exemplary embodiment, Dr/2+Dg/2+Db≤A can be set to ensure that as much light as possible emitted from the slope of the third light processing structure is incident on the corresponding red quantum dot layer or green quantum dot. layer. Taking the red quantum dot layer as an example, as shown in Figure 11, the cross-sectional length of the red quantum dot layer is Dr and the pixel opening length is C. The relationship between the two can be C＜Dr＜16+C, and the unit of the number in the formula is microns, the distance between the orthographic projection of the quantum dot layer 32 on the substrate 10 and the adjacent sides of the orthographic projection of the corresponding pixel opening on the substrate 10 is less than or equal to 8 microns. The relationship between the green quantum dot layer and the light-transmitting layer and the pixel opening length C can be the same as that of the red quantum dot layer.

(6) Form the color filter layer 60 and the module layer 70 patterns.

In an exemplary embodiment, forming the color filter layer 60 pattern may include: first coating a black matrix film on the substrate on which the foregoing pattern is formed, and patterning the black matrix film through a patterning process to form a second black matrix pattern; The second black matrix pattern may at least include a plurality of second black matrices 61 , and the plurality of second black matrices 61 may be arranged at intervals to form light-transmitting openings between adjacent second black matrices 61 . Subsequently, the red filter film, the blue filter film and the green filter film are sequentially coated, and the red filter film, the blue filter film and the green filter film are individually patterned through a patterning process. In the second black A plurality of filter layers are respectively formed in the light-transmitting openings formed by the matrix 1 . The module layer 70 can then be prepared using a module segment process.

At this point, the color filter layer 60 and the module layer 70 pattern are prepared, as shown in Figure 21. Figure 21 is a cross-sectional view along the A-A direction shown in Figure 3, illustrating the structure of three sub-pixels.

In an exemplary embodiment, the color filter layer 60 may include at least a plurality of second black matrices 61 and a plurality of filter layers 62 . A plurality of second black matrices 61 and a plurality of filter layers 62 may be disposed on a side of the light processing layer 50 away from the substrate 10 , and a plurality of second black matrices 61 may be disposed at intervals between adjacent second black matrices 61 To form a light-transmitting opening, multiple filter layers 62 may be spaced apart and may be provided in multiple light-transmitting openings. For example, a single filter layer 62 may be provided in a single light-transmitting opening, forming a layer separated by a second black matrix 61 . In an open filter layer array, the second black matrix 61 is located between adjacent filter layers 62 .

After the above preparation, the structure of the obtained display substrate is shown in Figure 21. The display substrate may also include other film layer structures, such as touch structure layers, protective layers and other structures, which can be prepared according to actual needs and will not be described again here.

The structures and preparation processes shown in the exemplary embodiments of the present disclosure are only illustrative. During actual implementation, the corresponding structure can be changed and the patterning process can be added or reduced according to actual needs, and this disclosure is not limited here.

Although the embodiments disclosed in the present disclosure are as above, the described contents are only used to facilitate the understanding of the present disclosure and are not intended to limit the present disclosure. Any person skilled in the field to which this disclosure belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope of this disclosure. However, the patent protection scope of this disclosure still must The scope is defined by the appended claims.

Claims

A display substrate, including: a substrate, a display structure layer provided on the substrate, a light conversion layer provided on the side of the display structure layer away from the substrate, and a light conversion layer provided on a side of the light conversion layer away from the substrate. The light processing layer on the side; the light conversion layer at least includes a red quantum dot layer, a green quantum dot layer and a light-transmitting layer. The light processing layer includes a plurality of light processing structures that improve light extraction efficiency and is arranged on the light processing structure. The covering layer on the side away from the substrate, the orthographic projection of the light processing structure on the substrate at least partially overlaps the orthographic projection of the red quantum dot layer on the substrate, the light processing structure is on the The orthographic projection on the substrate at least partially overlaps the orthographic projection of the green quantum dot layer on the substrate, and the refractive index of the light processing structure is greater than the refractive index of the covering layer.
The display substrate according to claim 1, wherein the light processing structure includes a first light processing structure, and an orthographic projection of the first light processing structure on the substrate includes the red quantum dot layer on the substrate. The orthographic projection of the first light processing structure on the substrate includes the orthographic projection of the green quantum dot layer on the substrate.
The display substrate according to claim 2, wherein the first light processing structure provided on the red quantum dot layer and the first light processing structure provided on the green quantum dot layer are spaced apart.
The display substrate according to claim 2, wherein the first light processing structure provided on the red quantum dot layer and the first light processing structure provided on the green quantum dot layer are connected to each other. integrated structure.
The display substrate according to claim 2, wherein in a plane perpendicular to the substrate, the cross-sectional shape of the first light processing structure is a trapezoid, the length of the upper base of the trapezoid is G1, and the length of the lower base is E1, the height is F1, and the size relationship of the trapezoid satisfies: 0.65 microns < (F1/((E1-G1)/2)) <0.99 microns.
The display substrate according to claim 1, wherein the light conversion layer further includes a first black matrix, the first black matrix is disposed between the red quantum dot layer, the green quantum dot layer and the light-transmitting layer;

The light processing structure includes a second light processing structure, the second light processing structure is disposed on a side of the light conversion layer away from the substrate, and the orthographic projection of the second light processing structure on the substrate is equal to Orthographic projections of the first black matrix on the substrate at least partially overlap;

There is no overlap between the orthographic projection of the second light processing structure on the substrate and the orthographic projection of the light-transmitting layer on the substrate.
The display substrate according to claim 6, wherein in a plane perpendicular to the substrate, the cross-sectional shape of the second light processing structure is a trapezoid, the length of the upper base of the trapezoid is G2, and the length of the lower base is E2, the height is F2, and the geometric size relationship of the trapezoid satisfies: 0.766 micron＜(F2/((E2-G2)/2))＜0.939 micron.
The display substrate according to claim 1, wherein the light conversion layer further includes a first black matrix, the first black matrix is disposed between the red quantum dot layer, the green quantum dot layer and the light-transmitting layer; The light processing structure includes a first light processing structure and a second light processing structure, and an orthographic projection of the first light processing structure on the substrate includes the red quantum dot layer and the green quantum dot layer on the substrate. The orthographic projection of the second light processing structure on the substrate at least partially overlaps with the orthographic projection of the first black matrix on the substrate, and the second light processing structure is on the substrate. There is no overlap between the orthographic projection of the light-transmitting layer on the substrate and the orthographic projection of the light-transmitting layer on the substrate.
The display substrate according to claim 8, wherein the first light processing structure is located on a side of the second light processing structure away from the substrate, and the refractive index of the second light processing structure is smaller than the first light processing structure. Refractive index of light processing structures.
The display substrate of claim 8, wherein the refractive index of the first light processing structure is set to be greater than or equal to 1.75 and less than or equal to 1.85.
The display substrate of claim 8, wherein the refractive index of the second light processing structure is set to be greater than or equal to 1.42 and less than or equal to 1.53.
The display substrate according to any one of claims 1 to 11, wherein the display structure layer includes a driving circuit layer, a light-emitting structure layer and a packaging structure layer sequentially stacked on the substrate; wherein the light-emitting structure layer The structural layer at least includes a pixel definition layer, with pixel openings provided on the pixel definition layer; the packaging structural layer includes a plurality of third light processing structures that improve light extraction efficiency, and the third light processing structures are on the substrate. The orthographic projection includes the orthographic projection of the pixel opening on the substrate.
The display substrate according to claim 12, wherein in a plane perpendicular to the substrate, the cross-sectional shape of the third light processing structure is a trapezoid, the length of the upper base of the trapezoid is G3, and the length of the lower base is E3, the height is F3, and the geometric size relationship of the trapezoid satisfies: 0.75 micron＜(F3/((E3-G3)/2))＜0.9 micron.
The display substrate according to claim 12, wherein the refractive index of the third light processing structure is set to be greater than or equal to 1.7 and less than or equal to 1.8.
The display substrate according to claim 13, wherein in a plane perpendicular to the substrate, the length of the pixel opening is C, and the size relationship between the third light processing structure and the pixel opening satisfies: C≤G3 <E3<C+8 micron.
The display substrate according to claim 15, wherein an orthographic projection of the quantum dot layer on the substrate includes an orthographic projection of the pixel opening on the substrate, and an orthographic projection of the quantum dot layer on the substrate The distance between the orthographic projection and adjacent sides of the orthographic projection of the pixel opening on the substrate is less than or equal to 8 microns.
The display substrate according to claim 15, wherein between adjacent pixel openings is a pixel dam, and in a plane perpendicular to the substrate, the length of the orthographic projection of the pixel dam on the substrate is A, so The cross-sectional length of the red quantum dot layer is Dr, the cross-sectional length of the green quantum dot layer is Dg, and the cross-sectional length of the first black matrix located between the red quantum dot layer and the green quantum dot layer is Db, Dr/2 +Dg/2+Db≤A.
A display device, characterized by comprising the display substrate according to any one of claims 1 to 17.
A method for preparing a display substrate, including: forming a display structure layer on a substrate;

A light conversion layer is formed on the side of the display structure layer away from the substrate, and the light conversion layer at least includes a red quantum dot layer, a green quantum dot layer and a light-transmitting layer;

A light processing layer is formed on the side of the light conversion layer away from the substrate. The light processing layer includes a plurality of light processing structures that improve light extraction efficiency and a covering layer disposed on the side of the light processing structure away from the substrate. , the orthographic projection of the light processing structure on the substrate at least partially overlaps with the orthographic projection of the red quantum dot layer on the substrate, and the orthographic projection of the light processing structure on the substrate overlaps with the orthographic projection of the red quantum dot layer on the substrate. Orthographic projections of the green quantum dot layer on the substrate at least partially overlap, and the refractive index of the light processing structure is greater than the refractive index of the cover layer.