Display substrate and display device

Abstract

A display substrate and a display device. The display substrate includes a base substrate, and a light-emitting structure layer, an encapsulation structure layer, and a cutoff filter layer sequentially stacked on the base substrate. The light-emitting structure layer includes a plurality of red light-emitting elements, green light-emitting elements, and blue light-emitting elements arranged at intervals. The cutoff filter layer includes a plurality of first cutoff filter units, second cutoff filter units, and third cutoff filter units arranged at intervals. The first cutoff filter units correspond to the red light-emitting elements and are configured to transmit only red light; the second cutoff filter units correspond to the green light-emitting elements and are configured to transmit only green light; and the third cutoff filter units correspond to the blue light-emitting elements and are configured to transmit only blue light.

Description

Technical Field

[0001] This article relates to but is not limited to display technology, and in particular to a display substrate and a display device. Background Art

[0002] In some technologies, the display substrate adopts a COE (color filter on encapsulation) structure, which adds a color filter layer on the encapsulation structure layer. However, the display substrate of this structure is thick and has poor bending resistance. Summary of the Invention

[0003] The following is a summary of the subject matter described in detail herein. This summary is not intended to limit the scope of the claims.

[0004] The embodiments of the present disclosure provide a display substrate and a display device, which solve the problems of large thickness and poor bending resistance of the display substrate.

[0005] In a first aspect, an embodiment of the present disclosure provides a display substrate, comprising a base substrate, and a light-emitting structure layer, an encapsulation structure layer, and a cutoff filter layer sequentially stacked on the base substrate, wherein the light-emitting structure layer comprises a plurality of red light-emitting elements, green light-emitting elements, and blue light-emitting elements arranged at intervals; the cutoff filter layer comprises a plurality of first cutoff filter units, second cutoff filter units, and third cutoff filter units arranged at intervals, the first cutoff filter unit corresponding to the red light-emitting element, and configured to transmit only red light; the second cutoff filter unit corresponding to the green light-emitting element, and configured to transmit only green light; the third cutoff filter unit corresponding to the blue light-emitting element, and configured to transmit only blue light.

[0006] In some exemplary embodiments, the display substrate includes a light-emitting area and a non-light-emitting area, the light-emitting area includes light-emitting elements of different colors; the non-light-emitting area includes an area outside the light-emitting area; the cut-off filter layer also includes a fourth cut-off filter unit, the fourth cut-off filter unit corresponds to the non-light-emitting area and is configured to reflect light.

[0007] In some exemplary embodiments, the fourth cutoff filter unit is a stacked structure, which includes a first stack, a second stack, and a third stack, the first stack being arranged on the same layer as the third cutoff filter unit, the second stack being arranged on the same layer as the second cutoff filter unit, and the third stack being arranged on the same layer as the first cutoff filter unit.

[0008] In some exemplary embodiments, the encapsulation structure layer includes a first inorganic encapsulation layer, an organic encapsulation layer, and a second inorganic encapsulation layer stacked in sequence, and the orthographic projection of the organic encapsulation layer on the base substrate is located within the range of the orthographic projection of the first inorganic encapsulation layer and the second inorganic encapsulation layer on the base substrate; or, the encapsulation structure layer includes a first inorganic encapsulation layer and an organic encapsulation layer stacked in sequence, and the orthographic projection of the organic encapsulation layer on the base substrate is located within the range of the orthographic projection of the first inorganic encapsulation layer on the base substrate.

[0009] In some exemplary embodiments, the encapsulation structure layer includes a first inorganic encapsulation layer, and a flat layer is arranged between the first inorganic encapsulation layer and the cut-off filter layer; the stacked structure of the fourth cut-off filter unit includes: the first cut-off filter unit, the second cut-off filter unit, the third cut-off filter unit, and a partition layer arranged between adjacent cut-off filter units.

[0010] In some exemplary embodiments, the cut-off filter layer is made of an inorganic material, and the inorganic material includes silicon dioxide and silicon nitride.

[0011] In some exemplary embodiments, the first cutoff filter unit includes a stacked first film layer, a second film layer, and a third film layer, wherein the first film layer includes a stack of nine first sub-layers, the first sub-layer being a stack of silicon nitride with a unit optical thickness and silicon dioxide with a thickness of 0.5 times the optical thickness; the second film layer includes a stack of nine second sub-layers, the second sub-layer being a stack of silicon dioxide with a thickness of 0.3 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness; the third film layer includes a stack of nine third sub-layers, the third sub-layer being a stack of silicon dioxide with a thickness of 0.6 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness.

[0012] In some exemplary embodiments, the second cutoff filter unit includes a stacked fourth film layer, a fifth film layer, and a sixth film layer, wherein the fourth film layer includes nine fourth sublayers stacked in sequence, and the fourth sublayer is a stack of silicon dioxide with a thickness of 0.05 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness; the fifth film layer includes nine fifth sublayers stacked in sequence, and the fifth sublayer is a stack of silicon dioxide with a thickness of 0.9 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness; the sixth film layer includes nine sixth sublayers stacked in sequence, and the sixth sublayer is a stack of silicon dioxide with a thickness of 1.2 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness.

[0013] In some exemplary embodiments, the third cutoff filter unit includes a stacked seventh film layer, an eighth film layer, and a ninth film layer, wherein the seventh film layer includes nine seventh sub-layers stacked in sequence, and the seventh sub-layer is a stack of silicon dioxide with a thickness of 0.5 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness; the eighth film layer includes nine eighth sub-layers stacked in sequence, and the eighth sub-layer is a stack of silicon dioxide with a thickness of 0.9 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness; the ninth film layer includes nine ninth sub-layers stacked in sequence, and the ninth sub-layer is a stack of silicon dioxide with a thickness of 1.3 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness.

[0014] In a second aspect, an embodiment of the present disclosure further provides a display device, comprising the display substrate in any of the above embodiments.

[0015] The display substrate provided by the embodiment of the present disclosure has a cutoff filter layer arranged on the side of the packaging structure layer away from the base substrate. Compared with the COE structure using a color film, the thickness of the cutoff filter layer structure is thinner, which can effectively reduce the overall thickness of the display substrate and improve the bending resistance of the screen.

[0016] Other features and advantages of the present disclosure will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present disclosure. Other advantages of the present disclosure can be realized and obtained through the solutions described in the description and the drawings.

[0017] Still other aspects will become apparent upon reading and understanding the accompanying drawings and detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings are used to provide an understanding of the technical solution of the present disclosure and constitute a part of the specification. Together with the embodiments of the present disclosure, they are used to explain the technical solution of the present disclosure and do not constitute a limitation to the technical solution of the present disclosure.

[0019] Figure 1 A schematic cross-sectional structure diagram of a display substrate provided by an exemplary embodiment;

[0020] Figure 2 A schematic diagram of the planar structure of a display substrate;

[0021] Figure 3 A schematic cross-sectional structure diagram of a display substrate provided in yet another exemplary embodiment;

[0022] Figure 4 A schematic cross-sectional structure diagram of a display substrate provided as yet another exemplary embodiment;

[0023] Figure 5 A schematic cross-sectional structure diagram of a display substrate provided as another exemplary embodiment;

[0024] Figure 6 Schematic diagram of transmittance of different wavelengths of light for different cut-off filter units shown in Table 1;

[0025] Figure 7 Schematic diagram of the reflectivity of different wavelengths of light for different cut-off filter units shown in Table 1;

[0026] Figure 8 Schematic diagram of the reflectivity of the fourth cutoff filter unit of the film structure shown in Table 1 to light of different wavelengths. DETAILED DESCRIPTION

[0027] The present disclosure describes a plurality of embodiments, but this description is exemplary rather than restrictive, and it will be apparent to those skilled in the art that there may be more embodiments and implementations within the scope of the embodiments described in the present disclosure. Although many possible feature combinations are shown in the drawings and discussed in the detailed description, many other combinations of the disclosed features are also possible. Unless specifically limited, any feature or element of any embodiment may be used in combination with any other feature or element in any other embodiment, or may replace any other feature or element in any other embodiment.

[0028] The present disclosure includes and contemplates combinations of features and elements known to those of ordinary skill in the art. The disclosed embodiments, features, and elements of the present disclosure may also be combined with any conventional features or elements to form a unique inventive solution defined by the claims. Any features or elements of any embodiment may also be combined with features or elements from other inventive solutions to form another unique inventive solution defined by the claims. Therefore, it should be understood that any feature shown and / or discussed in this disclosure may be implemented individually or in any appropriate combination. Therefore, the embodiments are not subject to other limitations except for the limitations set forth in the appended claims and their equivalents. In addition, various modifications and changes may be made within the scope of protection of the appended claims.

[0029] In addition, when describing representative embodiments, the specification may have presented the method and / or process as a specific sequence of steps. However, to the extent that the method or process does not rely on the specific order of the steps described herein, the method or process should not be limited to the steps in the specific order described. As will be understood by those skilled in the art, other orders of steps are also possible. Therefore, the specific order of the steps set forth in the specification should not be interpreted as a limitation on the claims. In addition, the claims to the method and / or process should not be limited to performing their steps in the order written, and those skilled in the art can readily understand that these orders can be changed and still remain within the spirit and scope of the disclosed embodiments.

[0030] In the drawings, the size of one or more components, layer thicknesses, or regions may be exaggerated for clarity. Therefore, one embodiment of the present disclosure is not necessarily limited to these dimensions, and the shapes and sizes of one or more components in the drawings do not reflect true proportions. Furthermore, the drawings schematically illustrate idealized examples, and one embodiment of the present disclosure is not limited to the shapes or values ​​shown in the drawings.

[0031] The scales of the figures in this disclosure can be used as a reference for actual processes, but are not limited to such. For example, the width-to-length ratio of the channel, the thickness and spacing of the various film layers, and the width and spacing of the various signal lines 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 this disclosure are merely schematic structural diagrams, and one embodiment of this disclosure is not limited to the shapes or values ​​shown in the figures.

[0032] In this specification, ordinal numbers such as "first," "second," and "third" are provided to avoid confusion among constituent elements, and are not intended to limit the number. "Multiple" in this disclosure means two or more.

[0033] In this specification, for convenience, words and phrases indicating orientation or positional relationships, such as "middle," "upper," "lower," "front," "back," "vertical," "horizontal," "top," "bottom," "inside," and "outside," are used to illustrate the positional relationships of constituent elements with reference to the accompanying drawings. This is merely for the purpose of facilitating the description of this specification and simplifying the description, and is not intended to indicate or imply that the device or element referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present disclosure. The positional relationships of constituent elements may be appropriately changed depending on the orientation of the constituent elements being described. Therefore, the present disclosure is not limited to the words and phrases described in the specification and may be appropriately replaced depending on the circumstances.

[0034] In this specification, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, or a detachable connection, or an integral connection; it can be a mechanical connection, or a connection; it can be a direct connection, or an indirect connection through an intermediate piece, or a connection between the two elements. For those of ordinary skill in the art, the meaning of the above terms in this disclosure can be understood according to the circumstances. Among them, "electrical connection" includes the situation where constituent elements are connected together through an element with some electrical function. There is no special restriction on "elements with some electrical function" as long as they can transmit electrical signals between connected constituent elements. Examples of "elements with some electrical function" include not only electrodes and wiring, but also switching elements such as transistors, resistors, inductors, capacitors, and other elements with one or more functions.

[0035] In this specification, a transistor refers to a device that includes at least three terminals: a gate electrode, a drain electrode, and a source electrode. A transistor has a channel region between a drain electrode (drain electrode terminal, drain region, or drain) and a source electrode (source electrode terminal, source region, or source), and current can flow through the drain electrode, the channel region, and the source electrode. Note that in this specification, the channel region refers to the region through which current primarily flows.

[0036] In this specification, the first electrode can be a drain electrode and the second electrode can be a source electrode, or vice versa. The functions of "source electrode" and "drain electrode" may be interchanged when using transistors with opposite polarity or when the direction of current changes during circuit operation. Therefore, in this specification, "source electrode" and "drain electrode" may be interchanged.

[0037] In this specification, the terms "film" and "layer" may be interchanged. For example, "conductive layer" may be replaced with "conductive film." Similarly, "insulating film" may be replaced with "insulating layer."

[0038] The triangles, rectangles, trapezoids, pentagons or hexagons in this specification are not in the strict sense, but may be approximate triangles, rectangles, trapezoids, pentagons or hexagons, etc. There may be some small deformations caused by tolerances, and there may be chamfers, arc edges and deformations.

[0039] The term "about" in the present disclosure refers to a numerical value that is not strictly defined and allows for process and measurement errors.

[0040] An embodiment of the present disclosure provides a display substrate, which includes a base substrate, and a light-emitting structure layer, an encapsulation structure layer, and a cutoff filter layer stacked in sequence on the base substrate, wherein the light-emitting structure layer includes a plurality of red light-emitting elements, green light-emitting elements, and blue light-emitting elements arranged at intervals; the cutoff filter layer includes a plurality of first cutoff filter units, second cutoff filter units, and third cutoff filter units arranged at intervals, the first cutoff filter unit corresponds to the red light-emitting element and is configured to only transmit red light; the second cutoff filter unit corresponds to the green light-emitting element and is configured to only transmit green light; the third cutoff filter unit corresponds to the blue light-emitting element and is configured to only transmit blue light.

[0041] The display substrate provided by the embodiment of the present disclosure has a cutoff filter layer arranged on the side of the packaging structure layer away from the base substrate. Compared with the COE structure using a color film, the thickness of the cutoff filter layer structure is thinner, which can effectively reduce the overall thickness of the display substrate and improve the bending resistance of the screen.

[0042] In some exemplary embodiments, the display substrate includes a light-emitting area and a non-light-emitting area, the light-emitting area includes light-emitting elements of different colors; the non-light-emitting area includes an area outside the light-emitting area; the cut-off filter layer also includes a fourth cut-off filter unit, the fourth cut-off filter unit corresponds to the non-light-emitting area and is configured to reflect light.

[0043] In this embodiment, a fourth cutoff filter unit is provided in the non-luminescent region, so that light passing through the non-luminescent region is reflected by the fourth cutoff filter unit, achieving a mirror display. Compared to the structure using a metal reflective film in some technologies, the use of a cutoff filter unit as a mirror reflective layer has higher reflectivity and better reliability. Furthermore, during manufacturing, the cutoff filter unit enables precise exposure and etching, facilitating accurate alignment with the light-emitting element.

[0044] In some exemplary embodiments, a cutoff filter unit corresponds to a light-emitting element, and the orthographic projection of the cutoff filter unit and the corresponding light-emitting element on the substrate may overlap. For example, a first cutoff filter unit corresponds to a red light-emitting element, and the orthographic projection of the first cutoff filter unit and the red light-emitting element on the substrate may overlap. A fourth cutoff filter unit corresponds to a non-luminescent area, and the orthographic projection of the fourth cutoff filter unit and the non-luminescent area on the substrate may overlap.

[0045] In some exemplary embodiments, a cutoff filter unit corresponds to a light-emitting element, and the cutoff filter unit and the corresponding light-emitting element's orthographic projection on the substrate may overlap. For example, a first cutoff filter unit corresponds to a red light-emitting element, and the first cutoff filter unit and the red light-emitting element's orthographic projection on the substrate may overlap. A fourth cutoff filter unit corresponds to a non-luminescent area, and the fourth cutoff filter unit and the non-luminescent area's orthographic projection on the substrate may overlap.

[0046] In some exemplary embodiments, the fourth cutoff filter unit is a stacked structure, which includes a first stack, a second stack, and a third stack, the first stack being arranged on the same layer as the third cutoff filter unit, the second stack being arranged on the same layer as the second cutoff filter unit, and the third stack being arranged on the same layer as the first cutoff filter unit.

[0047] In this embodiment, by using a stacked structure disposed in the same layer as the first, second, and third cutoff filter units as the fourth cutoff filter unit, the fourth cutoff filter unit can be prepared during the preparation of the first, second, and third cutoff filter units, resulting in a simple preparation process and high production efficiency. The stacking order of the first, second, and third stacks can be set as needed, and this is not limited by the present disclosure.

[0048] In some exemplary embodiments, the encapsulation structure layer includes a first inorganic encapsulation layer, an organic encapsulation layer, and a second inorganic encapsulation layer stacked in sequence, and the orthographic projection of the organic encapsulation layer on the base substrate is located within the range of the orthographic projection of the first inorganic encapsulation layer and the second inorganic encapsulation layer on the base substrate; or, the encapsulation structure layer includes a first inorganic encapsulation layer and an organic encapsulation layer stacked in sequence, and the orthographic projection of the organic encapsulation layer on the base substrate is located within the range of the orthographic projection of the first inorganic encapsulation layer on the base substrate.

[0049] The encapsulation structure layer can adopt a stacked structure consisting of a first inorganic encapsulation layer, an organic encapsulation layer, and a second inorganic encapsulation layer. Alternatively, the encapsulation structure layer can include the first inorganic encapsulation layer and the organic encapsulation layer, and the cutoff filter layer located on the side of the organic encapsulation layer away from the base substrate can function as the second inorganic encapsulation layer, further reducing the thickness of the display substrate.

[0050] In some exemplary embodiments, the encapsulation structure layer includes a first inorganic encapsulation layer, and a flat layer is arranged between the first inorganic encapsulation layer and the cut-off filter layer; the stacked structure of the fourth cut-off filter unit includes: the first cut-off filter unit, the second cut-off filter unit, the third cut-off filter unit, and a partition layer arranged between adjacent cut-off filter units.

[0051] In this embodiment, the encapsulation structure layer may include a first inorganic encapsulation layer. A planarization layer may be provided on the side of the first inorganic encapsulation layer away from the base substrate. The organic encapsulation layer may be omitted to reduce the thickness of the display substrate. The planarization layer may be made of, for example, optical clear adhesive (OCA). A separator layer may be provided between adjacent cutoff filter units in the fourth cutoff filter unit to help improve the accuracy of the stacking alignment of the fourth cutoff filter unit, further reduce the reflectivity of the non-luminescent area, and enhance the mirror display effect. The separator layer may be made of optical adhesive.

[0052] In some exemplary embodiments, the cut-off filter layer is made of an inorganic material.

[0053] In this embodiment, the film layer made of inorganic material is thinner and easier to achieve precise exposure and etching, which is beneficial for accurate alignment with the light-emitting element.

[0054] In some exemplary embodiments, the material of the cut-off filter layer includes silicon dioxide and silicon nitride.

[0055] The cutoff filter layer can be formed by stacking film layers formed of a high-refractive-index inorganic material and a low-refractive-index inorganic material. By adjusting the type and thickness of the stacked film layers, the first cutoff filter unit can have high transmittance only for red light (wavelength of approximately 650nm), the second cutoff filter unit can have high transmittance only for green light (wavelength of approximately 550nm), and the third cutoff filter unit can have high transmittance only for blue light (wavelength of approximately 405nm), while having high reflectivity for light of other wavelengths. The high-refractive-index inorganic material can be, for example, silicon nitride (SiNx), and the low-refractive-index inorganic material can be, for example, silicon dioxide (SiO2). The cutoff filter layer can also be prepared using other types of materials, and this disclosure is not limited to this.

[0056] In some exemplary embodiments, the first cutoff filter unit includes a stacked first film layer, a second film layer, and a third film layer, wherein the first film layer includes a stack of nine first sub-layers, the first sub-layer being a stack of silicon nitride with a unit optical thickness and silicon dioxide with a thickness of 0.5 times the optical thickness; the second film layer includes a stack of nine second sub-layers, the second sub-layer being a stack of silicon dioxide with a thickness of 0.3 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness; the third film layer includes a stack of nine third sub-layers, the third sub-layer being a stack of silicon dioxide with a thickness of 0.6 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness.

[0057] In other embodiments, each film layer of the first cutoff filter unit can adopt other ratios of silicon nitride and silicon dioxide, and the first cutoff filter unit can be stacked by film layers formed by any number and any type of materials, as long as the function of the first cutoff filter unit to only transmit red light can be achieved, and the present disclosure does not impose any restrictions on this.

[0058] In some exemplary embodiments, the second cutoff filter unit includes a stacked fourth film layer, a fifth film layer, and a sixth film layer, wherein the fourth film layer includes nine fourth sublayers stacked in sequence, and the fourth sublayer is a stack of silicon dioxide with a thickness of 0.05 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness; the fifth film layer includes nine fifth sublayers stacked in sequence, and the fifth sublayer is a stack of silicon dioxide with a thickness of 0.9 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness; the sixth film layer includes nine sixth sublayers stacked in sequence, and the sixth sublayer is a stack of silicon dioxide with a thickness of 1.2 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness.

[0059] In other embodiments, each film layer of the second cutoff filter unit can adopt other ratios of silicon nitride and silicon dioxide, and the second cutoff filter unit can be stacked by film layers formed by any number and any type of materials, as long as the function of the second cutoff filter unit to only transmit green light can be achieved, and the present disclosure does not impose any restrictions on this.

[0060] In some exemplary embodiments, the third cutoff filter unit includes a stacked seventh film layer, an eighth film layer, and a ninth film layer, wherein the seventh film layer includes nine seventh sub-layers stacked in sequence, and the seventh sub-layer is a stack of silicon dioxide with a thickness of 0.5 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness; the eighth film layer includes nine eighth sub-layers stacked in sequence, and the eighth sub-layer is a stack of silicon dioxide with a thickness of 0.9 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness; the ninth film layer includes nine ninth sub-layers stacked in sequence, and the ninth sub-layer is a stack of silicon dioxide with a thickness of 1.3 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness.

[0061] In other embodiments, each film layer of the third cutoff filter unit can adopt other ratios of silicon nitride and silicon dioxide, and the third cutoff filter unit can be stacked by film layers formed by any number and any type of materials, as long as the function of the third cutoff filter unit to only transmit green light can be achieved, and the present disclosure does not impose any restrictions on this.

[0062] In some exemplary embodiments, the substrate includes a base and a driving structure layer disposed on the base, the driving structure layer includes a pixel driving circuit, and the pixel driving circuit is configured to drive the light emitting element to emit light.

[0063] In some exemplary embodiments, the display substrate further comprises a protective layer, wherein the protective layer is located on a side of the cut-off filter layer away from the base substrate. In an exemplary embodiment, the protective layer may be made of optical adhesive.

[0064] The display substrate provided by the embodiments of the present disclosure is described below with reference to the accompanying drawings.

[0065] Figure 1 FIG. 1 is a schematic diagram of a cross-sectional structure of a display substrate provided by an exemplary embodiment. Figure 1As shown, the display substrate includes a base substrate 10, and a light-emitting structure layer 3, an encapsulation structure layer 4, and a cutoff filter layer 5 sequentially stacked on the base substrate 10. The light-emitting structure layer 3 includes a plurality of light-emitting elements spaced apart, including a red light-emitting element 31, a green light-emitting element 32, and a blue light-emitting element 33. The cutoff filter layer 5 includes a plurality of spaced-apart cutoff filter units, the orthographic projections of each cutoff filter unit on the base substrate 10 coinciding with the orthographic projections of the corresponding light-emitting element on the base substrate 10. The plurality of cutoff filter units include a first cutoff filter unit 51 corresponding to the red light-emitting element 31, a second cutoff filter unit 52 corresponding to the green light-emitting element 32, and a third cutoff filter unit 53 corresponding to the blue light-emitting element 33. The first cutoff filter unit 51 is configured to transmit only red light, the second cutoff filter unit 52 is configured to transmit only green light, and the third cutoff filter unit 53 is configured to transmit only blue light. The cutoff filter layer 5 can function as a color filter. Figure 1 In the description, one light-emitting element of each color is provided as an example, and the display substrate may include any number of light-emitting elements of different colors, which is not limited in the present disclosure.

[0066] Figure 2 FIG. 1 is a schematic diagram of a planar structure of a display substrate. Figure 2 As shown, the display substrate may include a plurality of light-emitting units P arranged in a matrix, at least one of the plurality of light-emitting units P including a red light-emitting element P1, a green light-emitting element P2, and a blue light-emitting element P3. Light-emitting elements of different colors may emit light under the drive of corresponding pixel driving circuits. Figure 2 The light-emitting elements in the display substrate constitute the light-emitting area, and the part of the display substrate other than the light-emitting elements is the non-light-emitting area.

[0067] In an exemplary embodiment, the light-emitting unit P may include a red light-emitting element, a green light-emitting element, a blue light-emitting element, and a white light-emitting element, which is not limited in this disclosure. In an exemplary embodiment, the shape of the light-emitting element in the light-emitting unit may be rectangular, rhombus, pentagonal, or hexagonal. When the light-emitting unit includes three light-emitting elements, the three light-emitting elements may be arranged horizontally, vertically, or in a triangular pattern. When the light-emitting unit includes four light-emitting elements, the four light-emitting elements may be arranged horizontally, vertically, or in a square pattern, which is not limited in this disclosure.

[0068] Figure 3 FIG. 1 is a schematic cross-sectional view of a display substrate provided by another exemplary embodiment. Figure 3As shown, the display substrate includes a base 1, and a driving structure layer 2, a light emitting structure layer 3, an encapsulation structure layer 4, a cut-off filter layer 5 and a protective layer 6 stacked on the base 1 in sequence. The base substrate 10 includes a base 1 and a driving structure layer 2. The driving structure layer 2 includes a pixel driving circuit, which is configured to drive the light emitting element to emit light. The light emitting structure layer 3 and the encapsulation structure layer 4 are connected to each other. Figure 1 The structure shown in FIG is the same as that shown in FIG, and the first cutoff filter unit 51, the second cutoff filter unit 52 and the third cutoff filter unit 53 of the cutoff filter layer 5 are the same as those shown in FIG. Figure 1 The structure shown in is the same as that shown in , and will not be repeated here. Figure 3 The middle encapsulation structure layer 4 includes a first inorganic encapsulation layer 41, an organic encapsulation layer 42, and a second inorganic encapsulation layer 43 stacked in sequence, wherein the orthographic projection of the organic encapsulation layer 42 on the base substrate 10 is located within the range of the orthographic projections of the first inorganic encapsulation layer 41 and the second inorganic encapsulation layer 43 on the base substrate 10 (not shown). The display substrate includes a light-emitting area and a non-light-emitting area. The light-emitting area includes all light-emitting elements. The non-light-emitting area surrounds the light-emitting area and includes other areas except the light-emitting area, such as Figure 3 As shown, the cutoff filter layer 5 also includes a fourth cutoff filter unit 54 corresponding to the non-luminescent area. The fourth cutoff filter unit 54 is a stacked structure, including a first cutoff filter unit 51, a second cutoff filter unit 52, and a third cutoff filter unit 53. It is configured to reflect light, thereby achieving a mirror display effect on the display substrate. A protective layer 6 is provided on the side of the cutoff filter layer 5 away from the base substrate 10 to smooth the surface of the display substrate.

[0069] Figure 4 FIG. 1 is a schematic cross-sectional view of a display substrate provided by another exemplary embodiment. Figure 4 As shown, the display substrate includes a base 1, and a driving structure layer 2, a light emitting structure layer 3, an encapsulation structure layer 4, a cut-off filter layer 5 and a protective layer 6 stacked on the base 1 in sequence. The base substrate 10 includes a base 1 and a driving structure layer 2. The driving structure layer 2, the light emitting structure layer 3, the cut-off filter layer 5 and the protective layer 6 are stacked on the base 1 in sequence. Figure 3 The structure is the same as that shown in , so it will not be described here. Figure 3 The difference is that Figure 4 The middle encapsulation structure layer 4 includes a first inorganic encapsulation layer 41 and an organic encapsulation layer 42 stacked in sequence, wherein the orthographic projection of the organic encapsulation layer 42 on the base substrate 10 is located within the range of the orthographic projection of the first inorganic encapsulation layer 41 on the base substrate 10 (not shown). Figure 4 In the structure shown, the cut-off filter layer 5 can play a role in Figure 3 The second inorganic encapsulation layer 43 plays a role in making the overall thickness of the substrate thinner.

[0070] Figure 5 FIG. 1 is a schematic cross-sectional view of a display substrate provided by another exemplary embodiment. Figure 5 As shown, the display substrate includes a base 1, and a driving structure layer 2, a light emitting structure layer 3, an encapsulation structure layer 4, a flat layer 7, a cut-off filter layer 5 and a protection layer 6 stacked on the base 1 in sequence. The base substrate 10 includes a base 1 and a driving structure layer 2. The driving structure layer 2, the light emitting structure layer 3 and the protection layer 6 are stacked on the base 1 in sequence. Figure 3 The structure is the same as that shown in , and will not be repeated here. Figure 5 As shown, the encapsulation structure layer 4 includes a first inorganic encapsulation layer 41. A flat layer 7 can be provided between the first inorganic encapsulation layer 41 and the cut-off filter layer 5. The flat layer 7 can play the following role: Figure 3 The organic encapsulation layer 42 and the second inorganic encapsulation layer 43 make the overall thickness of the display substrate thinner. The cut-off filter layer 5 includes a first cut-off filter unit 51, a second cut-off filter unit 52, a third cut-off filter unit 53 and a fourth cut-off filter unit 54. The fourth cut-off filter unit 54 is a stacked structure, including a first cut-off filter unit 51, a second cut-off filter unit 52, a third cut-off filter unit 53, and a partition layer arranged between adjacent cut-off filter units, which is arranged to reflect light. In the stacked structure of the fourth cut-off filter unit 54, by providing a partition layer between adjacent cut-off filter units, the accuracy of the stacking alignment of the fourth cut-off filter unit can be improved, and the reflectivity of the non-luminous area can be further reduced, thereby improving the effect of the mirror display.

[0071] Table 1 shows the film layer design of different cutoff filter units in an exemplary embodiment. In this embodiment, the materials of the cutoff filter layer include silicon dioxide and silicon nitride. The fourth cutoff filter unit can be regarded as a stack of the first cutoff filter unit, the second cutoff filter unit, and the third cutoff filter unit in Table 1. The left column in Table 1 shows the different cutoff filter units, and the right column shows the film layer structure of the different cutoff filter units. In the table, H represents silicon nitride, L represents silicon dioxide, each parenthesis represents a sublayer, and "^9" represents the number of sublayers in the preceding parentheses. The units of the numbers in the table are the optical thickness of the corresponding materials.

[0072] Table 1

[0073] Cutoff filter unit <![CDATA[Film layer structure (H: SiNx; L: SiO2)]]> First cutoff filter unit (H0.5L)^9(0.3LH0.5L)^9(0.6LH0.5L)^9 Second cutoff filter unit (0.05LH0.5L)^9(0.9LH0.5L)^9(1.2LH0.5L)^9 The third cutoff filter unit (0.5LH0.5L)^9(0.9LH0.5L)^9(1.3LH0.5L)^9

[0074] As shown in Table 1, the first cutoff filter unit includes a stacked first film layer, a second film layer, and a third film layer, wherein the first film layer includes nine first sub-layers (H0.5L) stacked in sequence, and the first sub-layer (H0.5L) is a stack of silicon nitride with a unit optical thickness and silicon dioxide with a thickness of 0.5 times the optical thickness; the second film layer includes nine second sub-layers (0.3LH0.5L) stacked in sequence, and the second sub-layer (0.3LH0.5L) is a stack of silicon dioxide with a thickness of 0.3 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness; the third film layer includes nine third sub-layers (0.6LH0.5L) stacked in sequence, and the third sub-layer (0.6LH0.5L) is a stack of silicon dioxide with a thickness of 0.6 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness.

[0075] The second cutoff filter unit includes a stacked fourth film layer, a fifth film layer and a sixth film layer, wherein the fourth film layer includes nine fourth sub-layers (0.05LH0.5L) stacked in sequence, and the fourth sub-layer (0.05LH0.5L) is a stack of silicon dioxide with 0.05 times the optical thickness, silicon nitride with a unit optical thickness and silicon dioxide with 0.5 times the optical thickness; the fifth film layer includes nine fifth sub-layers (0.9LH0.5L) stacked in sequence, and the fifth sub-layer (0.9LH0.5L) is a stack of silicon dioxide with 0.9 times the optical thickness, silicon nitride with a unit optical thickness and silicon dioxide with 0.5 times the optical thickness; the sixth film layer includes nine sixth sub-layers (1.2LH0.5L) stacked in sequence, and the sixth sub-layer (1.2LH0.5L) is a stack of silicon dioxide with 1.2 times the optical thickness, silicon nitride with a unit optical thickness and silicon dioxide with 0.5 times the optical thickness.

[0076] The third cutoff filter unit includes a stacked seventh film layer, an eighth film layer and a ninth film layer, wherein the seventh film layer includes nine seventh sub-layers (0.5LH0.5L) stacked in sequence, and the seventh sub-layer (0.5LH0.5L) is a stack of silicon dioxide with 0.5 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with 0.5 times the optical thickness; the eighth film layer includes nine eighth sub-layers (0.9LH0.5L) stacked in sequence, and the eighth sub-layer (0.9LH0.5L) is a stack of silicon dioxide with 0.9 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with 0.5 times the optical thickness; the ninth film layer includes nine ninth sub-layers (1.3LH0.5L) stacked in sequence, and the ninth sub-layer (1.3LH0.5L) is a stack of silicon dioxide with 1.3 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with 0.5 times the optical thickness.

[0077] Figure 6Schematic diagram of the transmittance of different wavelengths of light of different cut-off filter units shown in Table 1. Figure 6 The horizontal axis is the wavelength in nanometers (nm), the vertical axis is the transmittance, and the vertical axis value represents a percentage. R represents the first cutoff filter unit, G represents the second cutoff filter unit, and B represents the third cutoff filter unit. Figure 5 As shown, the first cutoff filter unit R has a high transmittance for red light (wavelength of approximately 650nm) and a low transmittance for light of other wavelengths. The second cutoff filter unit G has a high transmittance for green light (wavelength of approximately 550nm) and a low transmittance for light of other wavelengths. The third cutoff filter unit B has a high transmittance for blue light (wavelength of approximately 405nm) and a low transmittance for light of other wavelengths.

[0078] Figure 7 Schematic diagram of the reflectivity of different cut-off filter units to light of different wavelengths shown in Table 1. Figure 7 The horizontal axis is the wavelength in nanometers (nm), the vertical axis is the transmittance, and the vertical axis value represents a percentage. R represents the first cutoff filter unit, G represents the second cutoff filter unit, and B represents the third cutoff filter unit. Figure 6 As shown, the first cutoff filter unit R has a low reflectivity for red light (wavelength of approximately 650nm) and a high reflectivity for light of other wavelengths. The second cutoff filter unit G has a low reflectivity for green light (wavelength of approximately 550nm) and a high transmittance for light of other wavelengths. The third cutoff filter unit B has a low reflectivity for blue light (wavelength of approximately 405nm) and a high reflectivity for light of other wavelengths.

[0079] Figure 8 Schematic diagram of the reflectivity of the fourth cutoff filter unit for light of different wavelengths of the film structure shown in Table 1. The fourth cutoff filter unit can be regarded as a stack of the first cutoff filter unit, the second cutoff filter unit and the third cutoff filter unit of the film structure shown in Table 1. Figure 8 The horizontal axis is the wavelength, the unit is nanometer (nm), the vertical axis is the transmittance, and the vertical axis value represents the percentage. Figure 8 As shown, the fourth cut-off filter unit has a high reflectivity (about 99%) for light of different wavelengths. Figure 8 At the downward peak in the middle, the fourth cutoff filter unit also has a reflectivity of over 60%. This shows that the fourth cutoff filter unit, formed by stacking the first, second, and third cutoff filter units, has a good reflectivity for light of different wavelengths, and the non-luminous area has a good mirror-like display effect.

[0080] The present disclosure also provides a display device comprising the display substrate described in any of the above embodiments. The display device can be any product or component with a display function, such as an OLED display, a mobile phone, a tablet computer, a television, a monitor, a laptop computer, a digital photo frame, or a navigation system, but the present disclosure is not limited thereto.

[0081] The present disclosure provides a method for preparing a display substrate, comprising:

[0082] forming a light-emitting structure layer on a base substrate, wherein the light-emitting structure layer includes a plurality of red light-emitting elements, green light-emitting elements, and blue light-emitting elements that are spaced apart;

[0083] forming a packaging structure layer on the base substrate;

[0084] A cutoff filter layer is formed on the base substrate; the cutoff filter layer includes a plurality of first cutoff filter units, a second cutoff filter unit, and a third cutoff filter unit that are arranged at intervals, the first cutoff filter unit corresponds to the red light-emitting element and is configured to only transmit red light; the second cutoff filter unit corresponds to the green light-emitting element and is configured to only transmit green light; the third cutoff filter unit corresponds to the blue light-emitting element and is configured to only transmit blue light.

[0085] In the solution of the embodiment of the present disclosure, a cutoff filter layer is formed on the side of the packaging structure layer away from the base substrate. Compared with the COE structure using color film, the thickness of the cutoff filter layer is thinner, which can effectively reduce the overall thickness of the display substrate and improve the bending resistance of the screen.

[0086] In some exemplary embodiments, the display substrate includes a light-emitting area and a non-light-emitting area, the light-emitting area includes light-emitting elements of different colors; the non-light-emitting area includes an area outside the light-emitting area; the cut-off filter layer is formed on the base substrate, and further includes: forming a fourth cut-off filter unit on the base substrate, the fourth cut-off filter unit corresponding to the non-light-emitting area, and configured to reflect light.

[0087] In some exemplary embodiments, the forming of the encapsulation structure layer on the base substrate includes: sequentially forming a first inorganic encapsulation layer, an organic encapsulation layer, and a second inorganic encapsulation layer on the base substrate, the orthographic projection of the organic encapsulation layer on the base substrate being within the range of the orthographic projection of the first inorganic encapsulation layer and the second inorganic encapsulation layer on the base substrate; or, sequentially forming a first inorganic encapsulation layer and an organic encapsulation layer on the base substrate, the orthographic projection of the organic encapsulation layer on the base substrate being within the range of the orthographic projection of the first inorganic encapsulation layer on the base substrate.

[0088] In some exemplary embodiments, forming the packaging structure layer on the base substrate includes: forming a first inorganic packaging layer on the base substrate; before forming the cutoff filter layer on the base substrate, the method further includes: forming a flat layer on the first inorganic packaging layer.

[0089] The preparation process of the display substrate is exemplified below. The "patterning process" mentioned in the present disclosure includes processes such as coating photoresist, mask exposure, development, etching, and stripping photoresist for metal materials, inorganic materials or transparent conductive materials, and includes processes such as coating organic materials, mask exposure and development for organic materials. Deposition can be carried out by any one or more of sputtering, evaporation, and chemical vapor deposition, coating can be carried out by any one or more of spraying, spin coating and inkjet printing, and etching can be carried out by any one or more of dry etching and wet etching, which are not limited in the present disclosure. "Thin film" refers to a thin film made by deposition, coating or other processes of a certain material on a substrate. If the "thin film" does not require a patterning process during the entire production process, the "thin film" can also be called a "layer". If the "thin film" requires a patterning process during the entire production process, it is called a "thin film" before the patterning process and a "layer" after the patterning process. The "layer" after the patterning process contains at least one "pattern". As used in this disclosure, "A and B are disposed in the same layer" means that A and B are formed simultaneously through the same patterning process, and the "thickness" of the film layer refers to the dimension of the film layer in a direction perpendicular to the display substrate. In exemplary embodiments of this disclosure, "the orthographic projection of B is within the range of the orthographic projection of A" or "the orthographic projection of A contains the orthographic projection of B" means that the boundary of the orthographic projection of B falls within the boundary of the orthographic projection of A, or that the boundary of the orthographic projection of A overlaps with the boundary of the orthographic projection of B.

[0090] Figure 3 The preparation process of the display substrate may include the following steps.

[0091] (1) Forming a base substrate 10. A driving structure layer 2 is formed on the base substrate 1. In an exemplary embodiment, the driving structure layer 2 may include: a plurality of pixel driving circuits. The structure of the driving structure layer 2 can be designed as needed, and the present disclosure does not limit the structure and preparation process of the driving structure layer 2. The base substrate 10 includes a base substrate 1 and a driving structure layer 2.

[0092] (2) Forming the light emitting structure layer 3. In an exemplary embodiment, the light emitting structure layer 3 may include a plurality of red light emitting elements 31, green light emitting elements 32, and blue light emitting elements 33 arranged at intervals. Each light emitting element may include an anode, an organic light emitting layer, and a cathode. Forming the light emitting structure layer 3 may include:

[0093] A transparent conductive film is deposited on the patterned substrate 1 and patterned through a patterning process to form an anode (not shown). The anode is connected to the corresponding transistor of the pixel drive circuit in the drive structure layer 2. The transparent conductive film can be made of indium tin oxide (ITO) or indium zinc oxide (IZO).

[0094] Subsequently, on the substrate 1 with the aforementioned pattern formed thereon, an organic light-emitting layer pattern is sequentially formed by evaporation or inkjet printing.

[0095] Subsequently, a cathode pattern (not shown) is formed on the patterned substrate 1 by vapor deposition using an open mask. The cathode is connected to the organic light-emitting layer, achieving simultaneous connection of the organic light-emitting layer to both the anode and the first cathode. The cathode can be a reflective cathode and can be made of any one or more of magnesium (Mg), silver (Ag), aluminum (Al), copper (Cu), and lithium (Li), or an alloy of any one or more of these metals.

[0096] In exemplary embodiments, the organic light emitting layer may include an emission layer (EML), and any one or more of a hole injection layer (HIL), a hole transport layer (HTL), an electron blocking layer (EBL), a hole blocking layer (HBL), an electron transport layer (ETL), and an electron injection layer (EIL).

[0097] In an exemplary embodiment, the organic light emitting layer may be prepared in the following manner:

[0098] First, an open mask (OPM) evaporation process or an inkjet printing process is used to sequentially form a hole injection layer, a hole transport layer, and an electron blocking layer, thereby forming a common layer of the hole injection layer, the hole transport layer, and the electron blocking layer on a display substrate.

[0099] Subsequently, an open-mask evaporation process or inkjet printing is used to form different light-emitting layers in different sub-pixels. The light-emitting layers of adjacent sub-pixels can have a small overlap (for example, the overlap accounts for less than 10% of the area of ​​the respective light-emitting layer patterns) or can be isolated.

[0100] Subsequently, a hole blocking layer, an electron transport layer and an electron injection layer are sequentially formed by an open mask evaporation process or an inkjet printing process, thereby forming a common layer of the hole blocking layer, the electron transport layer and the electron injection layer on the display substrate.

[0101] In exemplary embodiments, the organic light-emitting layer may include a microcavity adjustment layer, such that the thickness of the organic light-emitting layer between the cathode and the anode satisfies 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 may be used as the microcavity adjustment layer, and this disclosure is not limited thereto.

[0102] In an exemplary embodiment, the light-emitting layer may include a host material and a guest material doped in the host material, with the doping ratio of the guest material in the light-emitting layer being between 1% and 20%. Within this doping ratio range, the host material in the light-emitting layer can effectively transfer exciton energy to the guest material in the light-emitting layer to stimulate the guest material to emit light. Furthermore, the host material in the light-emitting layer "dilutes" the guest material in the light-emitting layer, effectively improving the fluorescence quenching caused by collisions between guest material molecules and energy collisions, thereby improving the luminous efficiency and device life. In an exemplary embodiment, the doping ratio refers to the ratio of the mass of the guest material to the mass of the light-emitting layer, i.e., the mass percentage. In an exemplary embodiment, the host material and the guest material can be co-evaporated using a multi-source evaporation process so that the host material and the guest material are uniformly dispersed in the light-emitting layer. The doping ratio can be controlled by controlling the evaporation rate of the guest material during the evaporation process, or by controlling the ratio of the evaporation rates of the host material and the guest material. In an exemplary embodiment, the thickness of the light-emitting layer can be approximately 10 nm to 50 nm.

[0103] In an exemplary embodiment, the hole injection layer may be made of an inorganic oxide, such as molybdenum oxide, titanium oxide, vanadium oxide, rhenium oxide, ruthenium oxide, chromium oxide, zirconium oxide, hafnium oxide, tantalum oxide, silver oxide, tungsten oxide, or manganese oxide, or may be made of a p-type dopant of a strong electron-withdrawing system and a dopant of a hole transport material. In an exemplary embodiment, the hole injection layer may have a thickness of approximately 5 nm to 20 nm.

[0104] In an exemplary embodiment, the hole transport layer may be made of a material with high hole mobility, such as an aromatic amine compound, whose substituent group may be carbazole, methylfluorene, spirofluorene, dibenzothiophene, or furan. In an exemplary embodiment, the hole transport layer may have a thickness of approximately 40 nm to 150 nm.

[0105] In an exemplary embodiment, the hole blocking layer and the electron transport layer may be made of aromatic heterocyclic compounds, such as imidazole derivatives such as benzimidazole derivatives, imidazopyridine derivatives, and benzimidazolephenanthridine derivatives; oxazine derivatives such as pyrimidine derivatives and triazine derivatives; and compounds containing a nitrogen-containing six-membered ring structure such as quinoline derivatives, isoquinoline derivatives, and phenanthroline derivatives (including compounds having a phosphine oxide-based substituent on the heterocyclic ring). In an exemplary embodiment, 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.

[0106] In an exemplary embodiment, the electron injection layer may be made of an alkali metal or metal, such as lithium fluoride (LiF), ytterbium (Yb), magnesium (Mg), or calcium (Ca), or a compound of these alkali metals or metals. In an exemplary embodiment, the electron injection layer may have a thickness of approximately 0.5 nm to 2 nm.

[0107] (3) Forming a package structure layer pattern. In an exemplary embodiment, forming a package structure layer pattern may include:

[0108] On the substrate 1 with the aforementioned pattern, a first encapsulation film is first deposited using an open mask to form a pattern for the first inorganic encapsulation layer 41. Subsequently, an open mask is used to print a second encapsulation material using an inkjet printing process to form a pattern for the organic encapsulation layer 42. Subsequently, an open mask is used to deposit a third encapsulation film to form a pattern for the second inorganic encapsulation layer 43. At this point, the encapsulation structure layer pattern is complete. The encapsulation structure layer 4 may also have other structures, which are not limited in this disclosure.

[0109] In an exemplary embodiment, the first and third encapsulation films can be made of any one or more of silicon oxide (SiOx), silicon nitride (SiNx), and silicon oxynitride (SiON). They can be single-layer, multi-layer, or composite layers, ensuring that external water and oxygen cannot enter the light-emitting structure layer. Deposition methods such as chemical vapor deposition (CVD) or atomic layer deposition (ALD) can be used. The second encapsulation film can be made of an organic material, such as a resin, to cover the various film layers of the display substrate, improving structural stability and flatness.

[0110] (4) Forming a cutoff filter layer pattern. In an exemplary embodiment, forming a cutoff filter layer pattern may include:

[0111] Using PECVD equipment, a third cutoff filter unit material is deposited on the substrate 1 formed with the aforementioned pattern. The third cutoff filter unit material is patterned using a photolithography / etching process (or a photopatterning process) to form a first stack of third cutoff filter units 53 and fourth cutoff filter units 54. The orthographic projection of the third cutoff filter unit 53 on the substrate 1 coincides with the orthographic projection of the blue light-emitting element 33 on the substrate 1, and is configured to transmit only blue light. The first stack can cover the non-luminescent area.

[0112] Subsequently, a second cutoff filter unit material is deposited on the substrate 1 formed with the aforementioned pattern, and the second cutoff filter unit material is patterned using a photolithography / etching process to form a second stack of second cutoff filter units 52 and fourth cutoff filter units 54. The orthographic projection of the second cutoff filter unit 52 on the substrate 1 coincides with the orthographic projection of the green light-emitting element 32 on the substrate 1, and is configured to transmit only green light. The orthographic projection of the second stack on the substrate 1 coincides with the orthographic projection of the first stack on the substrate 1.

[0113] Subsequently, a first cutoff filter unit material is deposited on the substrate 1 forming the aforementioned pattern, and the first cutoff filter unit material is patterned using a photolithography / etching process to form a third stack of a first cutoff filter unit 51 and a fourth cutoff filter unit 54. The first cutoff filter unit 51 can correspond to the red light-emitting element 31 and is set to only transmit red light. The orthographic projection of the third stack on the substrate 1 coincides with the orthographic projection of the first stack on the substrate 1.

[0114] At this point, the cutoff filter layer 5 is completed.

[0115] The present disclosure does not limit the order of forming the cutoff filter units. The first cutoff filter unit, the second cutoff filter unit and the third cutoff filter unit can adopt the materials and film layer structures described in Table 1 above, and the present disclosure does not limit this. Figure 3 In the embodiment, the first stack is provided in the same layer as the third cutoff filter unit 53, the second stack is provided in the same layer as the second cutoff filter unit 52, and the third stack is provided in the same layer as the first cutoff filter unit 51. In other embodiments, the stacking order of the first stack, the second stack, and the third stack can be set as needed, and this disclosure is not limited thereto.

[0116] (5) Forming a protective layer pattern. In an exemplary embodiment, forming the protective layer pattern may include:

[0117] OC glue is coated on the substrate 1 with the aforementioned pattern formed thereon to form a protective layer 6 to make the surface of the display substrate smooth.

[0118] After the above preparation, the structure of the display substrate obtained is as follows Figure 3The display substrate may also include other film layer structures, such as a touch structure layer, etc., which can be prepared according to actual needs and will not be described in detail here.

[0119] Display substrates with other structures in the embodiments of the present disclosure can be prepared by referring to the above-mentioned preparation method, which will not be described in detail here.

[0120] The drawings in this disclosure only relate to the structures involved in this disclosure, and other structures may refer to general designs. In the absence of conflict, the embodiments of this disclosure, that is, the features in the embodiments, may be combined with each other to obtain new embodiments.

Claims

1. A display substrate, characterized in that: The display substrate includes a base substrate, and a light emitting structure layer, an encapsulation structure layer and a cutoff filter layer sequentially stacked on the base substrate, wherein: The light emitting structure layer includes a plurality of red light emitting elements, green light emitting elements and blue light emitting elements arranged at intervals; The cutoff filter layer includes a plurality of first cutoff filter units, second cutoff filter units, and third cutoff filter units that are spaced apart. The first cutoff filter units correspond to the red light-emitting elements and are configured to transmit only red light. The second cutoff filter units correspond to the green light-emitting elements and are configured to transmit only green light. The third cutoff filter units correspond to the blue light-emitting elements and are configured to transmit only blue light. The encapsulation structure layer comprises a first inorganic encapsulation layer and an organic encapsulation layer stacked in sequence, the orthographic projection of the organic encapsulation layer on the base substrate is located within the range of the orthographic projection of the first inorganic encapsulation layer on the base substrate, and the cut-off filter layer cooperates with the encapsulation structure layer to perform an encapsulation function; or The packaging structure layer includes the first inorganic packaging layer. A flat layer is provided between the first inorganic packaging layer and the cut-off filter layer. The flat layer cooperates with the packaging structure layer to perform a packaging function.

2. The display substrate according to claim 1, wherein: The display substrate includes a light-emitting area and a non-light-emitting area, wherein the light-emitting area includes light-emitting elements of different colors; and the non-light-emitting area includes an area outside the light-emitting area. The cutoff filter layer further includes a fourth cutoff filter unit, which corresponds to the non-luminescent area and is configured to reflect light.

3. The display substrate according to claim 2, wherein: The fourth cutoff filter unit is a stacked structure, which includes a first stack, a second stack and a third stack. The first stack is arranged on the same layer as the third cutoff filter unit, the second stack is arranged on the same layer as the second cutoff filter unit, and the third stack is arranged on the same layer as the first cutoff filter unit.

4. The display substrate according to claim 3, wherein: The stacked structure of the fourth cutoff filter unit includes: the first cutoff filter unit, the second cutoff filter unit, the third cutoff filter unit, and a separation layer arranged between adjacent cutoff filter units.

5. The display substrate according to claim 3, wherein: The cut-off filter layer is made of an inorganic material, which includes silicon dioxide and silicon nitride.

6. The display substrate according to claim 5, wherein: The first cutoff filter unit includes a stacked first film layer, a second film layer and a third film layer, wherein: The first film layer includes nine first sub-layers stacked in sequence, wherein the first sub-layer is a stack of silicon nitride with a unit optical thickness and silicon dioxide with a thickness of 0.5 times the optical thickness; The second film layer includes nine second sub-layers stacked in sequence, wherein the second sub-layer is a stack of silicon dioxide with a thickness of 0.3 times the optical thickness, silicon nitride with a thickness of unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness; The third film layer includes nine third sub-layers stacked in sequence, and the third sub-layer is a stack of silicon dioxide with 0.6 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with 0.5 times the optical thickness.

7. The display substrate according to claim 5, wherein: The second cutoff filter unit includes a stacked fourth film layer, a fifth film layer and a sixth film layer, wherein: The fourth film layer includes nine fourth sub-layers stacked in sequence, wherein the fourth sub-layer is a stack of silicon dioxide with a thickness of 0.05 times the optical thickness, silicon nitride with a thickness of unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness; The fifth film layer includes nine fifth sub-layers stacked in sequence, wherein the fifth sub-layer is a stack of silicon dioxide with a thickness of 0.9 times the optical thickness, silicon nitride with a thickness of unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness; The sixth film layer includes nine sixth sub-layers stacked in sequence, and the sixth sub-layer is a stack of silicon dioxide with 1.2 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with 0.5 times the optical thickness.

8. The display substrate according to claim 5, wherein: The third cutoff filter unit includes a seventh film layer, an eighth film layer and a ninth film layer stacked together, wherein: The seventh film layer includes nine seventh sub-layers stacked in sequence, wherein the seventh sub-layer is a stack of silicon dioxide with a thickness of 0.5 times the optical thickness, silicon nitride with a thickness of unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness; The eighth film layer includes nine eighth sub-layers stacked in sequence, wherein the eighth sub-layer is a stack of silicon dioxide with a thickness of 0.9 times the optical thickness, silicon nitride with a thickness of unit optical thickness, and silicon dioxide with a thickness of 0.5 times the optical thickness; The ninth film layer includes nine ninth sub-layers stacked in sequence, and the ninth sub-layer is a stack of silicon dioxide with 1.3 times the optical thickness, silicon nitride with a unit optical thickness, and silicon dioxide with 0.5 times the optical thickness.

9. A display device, characterized in that: The display substrate comprises the display substrate according to any one of claims 1 to 8.

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