Display panel and display device

Abstract

The invention discloses a display panel and a display device. The display panel comprises a substrate, a first electrode layer, a first light-emitting layer, a second light-emitting layer and a second electrode layer. The substrate comprises a plurality of sub-pixel regions including a first sub-pixel region, a second sub-pixel region and a third sub-pixel region. The first electrode layer comprises a plurality of first electrodes, and each first electrode is provided with a reflecting surface; the light-emitting color of the first light-emitting layer is basically the same as the light-emitting color of the first sub-pixel area. The second light-emitting layer is arranged on the side, away from the substrate, of the first light-emitting layer, and the light-emitting wavelength of the second light-emitting layer is larger than that of the first light-emitting layer. In the direction perpendicular to the substrate, the distances between the first light-emitting layers and the reflecting surfaces of the first sub-pixel area, the second sub-pixel area and the third sub-pixel area are the first distance, the second distance and the third distance respectively, the first distance is larger than the second distance, and the first distance is larger than the third distance.

Description

Technical Field

[0001] The present disclosure belongs to the field of display technology, and in particular, relates to a display panel and a display device. Background Art

[0002] White light OLED (Organic Light-Emitting Diode) technology has the advantages of low cost, short response time, high brightness, low driving voltage and flexible light source. It can be applied to display fields such as smart phones, computers, and televisions.

[0003] The commonly used multi-light-emitting layer white light OLED mixes the monochromatic light emitted by different light-emitting layers into white light, and uses the anode and cathode to form a microcavity, thereby producing a microcavity effect on the light-emitting characteristics so that the light emitted by the light-emitting layer forms strong interference of multiple light beams in the microcavity, and light of a specific wavelength is selected and amplified. Summary of the invention

[0004] The embodiments of the present disclosure provide a display panel and a display device, so that the microcavity in the first sub-pixel area can gain light emitted by the first light-emitting layer while effectively suppressing light emitted by the second light-emitting layer, thereby improving the light extraction efficiency of the first sub-pixel area.

[0005] Other features and advantages of the present disclosure will become apparent from the following detailed description, or may be learned in part by the practice of the present disclosure.

[0006] A first aspect of the present disclosure provides a display panel, comprising:

[0007] A substrate, comprising a plurality of sub-pixel regions, wherein the plurality of sub-pixel regions include a first sub-pixel region, a second sub-pixel region and a third sub-pixel region;

[0008] A first electrode layer is arranged on one side of the base substrate, the first electrode layer comprises a plurality of first electrodes arranged at intervals, the orthographic projections of the first electrodes on the base substrate are at least partially located in the sub-pixel area, and the first electrodes have a reflective surface;

[0009] A first light-emitting layer is arranged on a side of the first electrode layer away from the base substrate, the orthographic projection of the first light-emitting layer on the base substrate is at least partially located in the plurality of sub-pixel regions, and the light emission color of the first light-emitting layer is substantially the same as the light emission color of the first sub-pixel region;

[0010] A second light-emitting layer is disposed on a side of the first light-emitting layer away from the base substrate, the orthographic projection of the second light-emitting layer on the base substrate is at least partially located within the plurality of sub-pixel regions, and the light emission wavelength of the second light-emitting layer is greater than the light emission wavelength of the first light-emitting layer;

[0011] A second electrode layer is arranged on a side of the second light-emitting layer away from the base substrate, and the second electrode layer has the characteristics of partially transmitting and partially reflecting the light emitted by the first light-emitting layer and / or the light emitted by the second light-emitting layer;

[0012] Among them, along the direction perpendicular to the base substrate, the distance between the first light-emitting layer and the reflective surface of the first sub-pixel area is a first distance, the distance between the first light-emitting layer and the reflective surface of the second sub-pixel area is a second distance, and the distance between the first light-emitting layer and the reflective surface of the third sub-pixel area is a third distance, the first distance is greater than the second distance, and the first distance is greater than the third distance.

[0013] Optionally, in a direction perpendicular to the base substrate, a thickness of the first electrode of the first sub-pixel region is greater than a thickness of the first electrode of the second sub-pixel region, and a thickness of the first electrode of the first sub-pixel region is greater than a thickness of the first electrode of the third sub-pixel region.

[0014] Optionally, the first electrode comprises:

[0015] A reflective layer, arranged on one side of the base substrate, wherein a side of the reflective layer away from the base substrate is the reflective surface;

[0016] An adjustment layer, disposed on a side of the reflective layer away from the base substrate, the adjustment layer comprising a via hole;

[0017] A conductive layer, disposed on a side of the adjustment layer away from the base substrate, and electrically connected to the reflective layer through the via hole;

[0018] In a direction perpendicular to the base substrate, the thickness of the adjustment layer in the first sub-pixel region is greater than the thickness of the adjustment layer in the second sub-pixel region, and the thickness of the adjustment layer in the first sub-pixel region is greater than the thickness of the adjustment layer in the third sub-pixel region.

[0019] Optionally, the light emission wavelength of the second sub-pixel region is smaller than the light emission wavelength of the third sub-pixel region, and the thickness of the adjustment layer in the second sub-pixel region is smaller than the thickness of the adjustment layer in the third sub-pixel region.

[0020] Optionally, the thickness range of the adjustment layer in the first sub-pixel area is 1300 angstroms to 1600 angstroms; the thickness range of the adjustment layer in the second sub-pixel area is 300 angstroms to 600 angstroms; the thickness range of the adjustment layer in the third sub-pixel area is 1200 angstroms to 1500 angstroms.

[0021] Optionally, the thickness of the adjustment layer in each of the sub-pixel regions is different, the thickness of the conductive layer in each of the sub-pixel regions is substantially the same, and the thickness of the reflective layer in each of the sub-pixel regions is substantially the same.

[0022] Optionally, the second light-emitting layer is configured to emit a first light and a second light, the color of the first light is basically the same as the light emission color of the second sub-pixel area, the color of the second light is basically the same as the light emission color of the third sub-pixel area, and the emission wavelength of the first light is smaller than the emission wavelength of the second light.

[0023] Optionally, the second light-emitting layer includes:

[0024] A first sub-light emitting layer is arranged on a side of the first light emitting layer away from the base substrate, an orthographic projection of the first sub-light emitting layer on the base substrate is at least partially located within the plurality of sub-pixel regions, the first sub-light emitting layer is configured to emit a first light, and a color of the first light is substantially the same as a color of light emitted from the second sub-pixel region;

[0025] A second sub-light emitting layer is arranged on a side of the first sub-light emitting layer away from the base substrate, and the orthographic projection of the second sub-light emitting layer on the base substrate is at least partially located within the plurality of sub-pixel regions. The second sub-light emitting layer is configured to emit a second light, and the color of the second light is substantially the same as the color of light emitted from the third sub-pixel region, and the emission wavelength of the first light is smaller than the emission wavelength of the second light.

[0026] Optionally, in a direction perpendicular to the substrate, a fourth distance exists between the first sub-light emitting layer in the second sub-pixel region and the reflective surface, a fifth distance exists between the second sub-light emitting layer in the third sub-pixel region and the reflective surface, the fifth distance is greater than the fourth distance, the fifth distance is greater than the first distance, and the fourth distance is less than the first distance.

[0027] Optionally, the value range of the first distance is: 1500 angstroms-2000 angstroms; the value range of the fourth distance is: 1500 angstroms-2000 angstroms; the value range of the fifth distance is: 2250 angstroms-2750 angstroms.

[0028] Optionally, along a direction perpendicular to the substrate, the distance between the reflective surface and the second electrode layer is the microcavity length;

[0029] The ratio of the microcavity length of the first sub-pixel region to half the emission wavelength of the first light-emitting layer is N1, the ratio of the microcavity length of the second sub-pixel region to half the emission wavelength of the first sub-light-emitting layer is N2, and the ratio of the microcavity length of the third sub-pixel region to half the emission wavelength of the second sub-light-emitting layer is N3, wherein N1, N2 and N3 are positive integers, N1 is greater than N2 and N1 is greater than N3.

[0030] Optionally, in a direction perpendicular to the base substrate, a sixth distance exists between a side of the first light-emitting layer close to the base substrate and a side of the first electrode far from the base substrate, a seventh distance exists between a side of the first light-emitting layer far from the base substrate and a side of the first sub-light-emitting layer close to the base substrate, and an eighth distance exists between a side of the second sub-light-emitting layer far from the base substrate and a side of the second electrode layer close to the base substrate;

[0031] Among them, the sixth distance is greater than the eighth distance, and the eighth distance is greater than the seventh distance.

[0032] Optionally, in a direction perpendicular to the base substrate, the distance between the first light-emitting layer and the second electrode layer in each of the sub-pixel regions is substantially the same.

[0033] Optionally, the first light-emitting layer is configured to emit blue light, and the second light-emitting layer is configured to emit green light and red light.

[0034] A second aspect of the embodiments of the present disclosure provides a display device, comprising a display panel as described in any one of the first aspects.

[0035] The display panel provided by the embodiment of the present disclosure includes: a base substrate, a first electrode layer, a first light-emitting layer, a second light-emitting layer, and a second electrode layer. The base substrate includes a plurality of sub-pixel areas, and the plurality of sub-pixel areas include a first sub-pixel area, a second sub-pixel area, and a third sub-pixel area. The first electrode layer is arranged on one side of the base substrate, and the first electrode layer includes a plurality of first electrodes arranged at intervals, and the orthographic projection of the first electrode on the base substrate is at least partially located in the sub-pixel area, and the first electrode has a reflective surface. The first light-emitting layer is arranged on a side of the first electrode layer away from the base substrate, and the orthographic projection of the first light-emitting layer on the base substrate is at least partially located in the plurality of sub-pixel areas, and the light-emitting color of the first light-emitting layer is substantially the same as the light-emitting color of the first sub-pixel area. The second light-emitting layer is arranged on a side of the first light-emitting layer away from the substrate, the orthographic projection of the second light-emitting layer on the substrate is at least partially located in a plurality of sub-pixel regions, and the light-emitting wavelength of the second light-emitting layer is greater than the light-emitting wavelength of the first light-emitting layer; the second electrode layer is arranged on a side of the second light-emitting layer away from the substrate; wherein, along a direction perpendicular to the substrate, the distance between the first light-emitting layer and the reflective surface in the first sub-pixel region is a first distance, the distance between the first light-emitting layer and the reflective surface in the second sub-pixel region is a second distance, the distance between the first light-emitting layer and the reflective surface in the third sub-pixel region is a third distance, the first distance is greater than the second distance, and the first distance is greater than the third distance.

[0036] Thus, the present disclosure forms a microcavity between the reflective surface of the first electrode and the second electrode layer to select and gain light of a specific wavelength in each sub-pixel region, so that different sub-pixel regions emit light of different colors. The light-emitting wavelength of the first light-emitting layer is smaller than the light-emitting wavelength of the second light-emitting layer, and the first light-emitting layer is closer to the substrate than the second light-emitting layer. The present disclosure increases the length of the microcavity in the first sub-pixel region, that is, the first distance is greater than the second distance and the first distance is greater than the third distance, so that the microcavity in the first sub-pixel region can gain the light emitted by the first light-emitting layer while effectively suppressing the light emitted by the second light-emitting layer, thereby improving the light extraction efficiency of the first sub-pixel region.

[0037] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The drawings herein are incorporated into the specification and constitute a part of the specification, showing embodiments consistent with the present disclosure, and together with the specification, are used to explain the principles of the present disclosure. Obviously, the drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0039] Figure 1A partial cross-sectional structural schematic diagram of a display panel in the related art is shown;

[0040] Figure 2 A schematic diagram of a partial cross-sectional structure of a pixel unit in the related art is shown;

[0041] Figure 3 A schematic diagram of a first partial cross-sectional structure of a display panel according to an embodiment of the present disclosure is shown;

[0042] Figure 4 A second partial cross-sectional structural schematic diagram of a display panel according to an embodiment of the present disclosure is shown;

[0043] Figure 5 A third partial cross-sectional structural schematic diagram of the display panel according to the embodiment of the present disclosure is shown;

[0044] Figure 6 A schematic diagram of a partial cross-sectional structure of a first electrode layer according to an embodiment of the present disclosure is shown;

[0045] Figure 7 A fourth partial cross-sectional structural schematic diagram of a display panel according to an embodiment of the present disclosure is shown;

[0046] Figure 8 A fifth partial cross-sectional structural schematic diagram of the display panel according to the embodiment of the present disclosure is shown;

[0047] Fig. 9 A structural block diagram of a display device according to an embodiment of the present disclosure is shown.

[0048] Among them, 100-display panel; 10-base substrate; 11-anode layer; 111-anode; 112-reflection surface; 12-blue light-emitting layer; 13-green light-emitting layer; 14-red light-emitting layer; 15-cathode layer; 16-red sub-pixel area; 17-green sub-pixel area; 18-blue sub-pixel area; 200-display panel; 20-base substrate; 21-first sub-pixel area; 22-second sub-pixel area; 23-third sub-pixel area; 24-first electrode layer; 241-first electrode; 241A-reflection layer; 241B-adjustment layer; 241C-conductive layer; 25-first light-emitting layer; 2 6-second light-emitting layer; 26A-first sub-light-emitting layer; 26B-second sub-light-emitting layer; 27-second electrode layer; 271-second electrode; 31-hole injection layer; 32-first hole transport layer; 33-first electron transport layer; 34-N-type charge transport layer; 35-P-type charge transport layer; 36-second hole transport layer; 37-second electron transport layer; 38-pixel definition layer; 39-first isolation structure layer; 40-second isolation structure layer; 41-encapsulation layer; 42-first encapsulation layer; 43-second encapsulation layer; 44-third encapsulation layer; 45-organic light-emitting functional layer; 300-display device. DETAILED DESCRIPTION

[0049] The following will be combined with the drawings in the embodiments of the present disclosure to clearly and completely describe the technical solutions in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present disclosure.

[0050] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities may be implemented in software form, or in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.

[0051] The flowcharts shown in the accompanying drawings are only exemplary and do not necessarily include all the contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps can be decomposed, and some operations / steps can be combined or partially combined, so the actual execution order may change according to actual conditions.

[0052] It should also be noted that the terms "first", "second", etc. in the specification and claims of the present disclosure and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the objects used in this way can be interchanged where appropriate, so that the embodiments of the present disclosure described herein can be implemented in an order other than those shown or described.

[0053] As used herein, "about," "approximately," "substantially" includes the stated value and the average value that is within an acceptable range of deviation from the particular value, where the acceptable range of deviation is determined by one of ordinary skill in the art taking into account the measurements in question and the errors associated with the measurement of the particular quantity (i.e., the limitations of the measurement system).

[0054] As used herein, "parallel", "perpendicular", and "equal" include the situations described and situations similar to the situations described, and the range of the similar situations is within the acceptable deviation range, wherein the acceptable deviation range is determined by a person of ordinary skill in the art taking into account the measurement in question and the errors associated with the measurement of a particular quantity (i.e., the limitations of the measurement system). For example, "parallel" includes absolute parallelism and approximate parallelism, wherein the acceptable deviation range of approximate parallelism may be, for example, a deviation within 5°; "perpendicular" includes absolute perpendicularity and approximate perpendicularity, wherein the acceptable deviation range of approximate perpendicularity may also be, for example, a deviation within 5°. "Equal" includes absolute equality and approximate equality, wherein the acceptable deviation range of approximate equality may be, for example, the difference between the two equalities is less than or equal to 5% of either one.

[0055] The proportions of the drawings in this disclosure can be used as a reference in the actual process, but are not limited to this. For example: the width-to-length ratio of the channel, the thickness and spacing of each film layer, 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 drawings described in this disclosure are only structural schematic diagrams, and one method of this disclosure is not limited to the shapes or values ​​shown in the drawings.

[0056] 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, a detachable connection, or an integral connection; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate, or the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this disclosure can be understood according to specific circumstances.

[0057] 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, the channel region, and the source electrode. Note that in this specification, the channel region refers to a region where current mainly flows.

[0058] 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. In the case of using transistors with opposite polarities or when the direction of current changes during circuit operation, the functions of the "source electrode" and the "drain electrode" are sometimes interchanged. Therefore, in this specification, the "source electrode" and the "drain electrode" may be interchanged.

[0059] In this specification, "electrical connection" includes the case where components are connected together through an element having some electrical function. There is no particular limitation on the "element having some electrical function" as long as it can transmit and receive electrical signals between the connected components. Examples of "element having some electrical function" include not only electrodes and wiring, but also switching elements such as transistors, resistors, inductors, capacitors, and other elements having various functions.

[0060] In this specification, "film" and "layer" may be interchanged. For example, "conductive layer" may be replaced by "conductive film". Similarly, "insulating film" may be replaced by "insulating layer".

[0061] The triangles, rectangles, trapezoids, pentagons or hexagons in this specification are not in the strict sense, and 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.

[0062] The term "about" in the present disclosure refers to a numerical value that is not strictly limited to a limit and allows for process and measurement errors.

[0063] In recent years, organic light-emitting diode (OLED) technology has been gradually applied. Organic light-emitting diode has the characteristics of active light emission, high brightness, high resolution, wide viewing angle, fast response speed, low energy consumption and flexibility, and has become a mainstream display product.

[0064] OLED devices are usually multi-layer thin-film devices with multiple functional layers. Organic electroluminescent devices with good efficiency and long life are usually the result of optimized matching of various organic materials, which provides great opportunities and challenges for the design and development of functional materials and device structures of various structures.

[0065] In traditional designs, the display screen is generally composed of RGB (Red Green Blue) three-color pixels. Each color pixel requires an independent light-emitting device, and the three colors of pixels require three light-emitting devices with different structures. Therefore, in the preparation process, it is necessary to prepare a fine mask plate, and the cost of the fine mask plate is relatively high, which in turn leads to a high production cost of OLED light-emitting devices.

[0066] With the development of OLED technology, white OLED (WOLED) has gradually been used in display products due to its advantages of low cost, short response time, high brightness, low driving voltage and flexible light source. For example, white OLED can be used in display fields such as smart phones, computers, and TVs.

[0067] Commonly used white light OLEDs include multiple light-emitting layers. Monochromatic light emitted by different light-emitting layers is mixed into white light. A microcavity is formed by the anode and the cathode. The light emitted by the light-emitting layer is confined within the microcavity formed by the anode and the cathode. When the cavity length of the microcavity is at the same order of magnitude as the wavelength of the light emitted by the light-emitting layer, a microcavity effect is generated on the light-emitting characteristics so that the light emitted by the light-emitting layer forms a strong interference of multiple light beams in the microcavity, so that light of a specific wavelength is selected and amplified. As a result, white light OLEDs can emit light of different colors in different sub-pixel areas. For example, for RGB pixels, in the red sub-pixel area, the light emitted by the red light-emitting layer is amplified by the microcavity, and green and blue light are suppressed, so that the red sub-pixel area emits red light; in the green sub-pixel area, the light emitted by the green light-emitting layer is amplified by the microcavity, and red and blue light are suppressed, so that the green sub-pixel area emits green light; in the blue sub-pixel area, the light emitted by the blue light-emitting layer is amplified by the microcavity, and green and red light are suppressed, so that the blue sub-pixel area emits blue light.

[0068] Here, the microcavity technology is further explained. It is understood that when the anode and the cathode have reflective properties, the multiple beams of light emitted by the light-emitting layer between the anode and the cathode may be reflected multiple times in the microcavity between the anode and the cathode. If the length of the microcavity is in the same order of magnitude as the wavelength of the light emitted by the light-emitting layer, and there is a corresponding relationship between the two, it is possible to select and gain light of a specific wavelength. For example, if the period of the two beams of light is the same, the two beams of light will meet at the crest and at the trough. Then, after the two beams of light are superimposed, the intensity of the beam will be enhanced (gain); conversely, if the crests of the two beams of light are misaligned, or the troughs are misaligned, then the intensity of the two beams of light will be weakened (suppressed) after superposition. Corresponding to white light OLED, if multiple beams of light emitted by a certain light-emitting layer interfere with each other between the anode and the cathode, if the two beams of light are superimposed together and the optical path difference between the two is periodic, then the light intensity will be gained after the two beams of light are superimposed. If the optical path difference between the two is non-periodic, then the light intensity will be weakened after the two beams of light are superimposed.

[0069] At present, the mainstream structures of white light OLED devices include: the first is a blue light-emitting layer and a yellow light-emitting layer, and the second is a blue light-emitting layer, a green light-emitting layer, and a red light-emitting layer. Among them, the device structure of the blue light-emitting layer and the yellow light-emitting layer has the advantages of high luminous efficiency and high brightness, but because the yellow light emitted by the yellow light-emitting layer has a higher fluorescence intensity than the blue light emitted by the blue light-emitting layer, the white light mixed by the blue light-emitting layer and the yellow light-emitting layer is generally warm white light, and the color gamut is worse than the color gamut of the white light emitted by the device structure of the blue light-emitting layer, the green light-emitting layer, and the red light-emitting layer. Therefore, the white light OLED device of the blue light-emitting layer, the green light-emitting layer, and the red light-emitting layer is used as an example for the following description of the embodiment of the present disclosure.

[0070] Figure 1A partial cross-sectional structural schematic diagram of a display panel in the related art is shown; Figure 2 A schematic diagram of a partial cross-sectional structure of a pixel unit of a display panel in the related art is shown.

[0071] like Figure 1 and Figure 2 As shown, the display panel 100 includes: a base substrate 10 , an anode layer 11 , a blue light emitting layer 12 , a green light emitting layer 13 , a red light emitting layer 14 and a cathode layer 15 .

[0072] The substrate 10 includes a plurality of pixel units arranged in an array, the pixel units include a plurality of sub-pixel regions, the plurality of sub-pixel regions include a red sub-pixel region, a green sub-pixel region and a blue sub-pixel region; an anode layer 11 is arranged on one side of the substrate 10, the anode layer 11 includes a plurality of anodes 111 arranged at intervals, the orthographic projection of the anode 111 on the substrate 10 is at least partially located in the sub-pixel region, and the anode 111 has a reflecting surface 112; a blue light-emitting layer 12 is arranged on a side of the anode layer 11 away from the substrate 10, the orthographic projection of the blue light-emitting layer 12 on the substrate 10 is at least partially located in the plurality of sub-pixel regions, and the light-emitting color of the blue light-emitting layer 12 is consistent with the light output of the blue sub-pixel region The colors are basically the same; the green light-emitting layer 13 is arranged on the side of the blue light-emitting layer 12 away from the substrate 10, the orthographic projection of the green light-emitting layer 13 on the substrate 10 is at least partially located in multiple sub-pixel areas, and the light-emitting wavelength of the green light-emitting layer 13 is greater than the light-emitting wavelength of the blue light-emitting layer 12; the red light-emitting layer 14 is arranged on the side of the green light-emitting layer 13 away from the substrate 10, the orthographic projection of the red light-emitting layer 14 on the substrate 10 is at least partially located in multiple sub-pixel areas, and the light-emitting wavelength of the red light-emitting layer 14 is greater than the light-emitting wavelength of the green light-emitting layer 13; the cathode layer 15 is arranged on the side of the second light-emitting layer away from the substrate 10, and has the characteristics of partial transmission and partial reflection. Among them, in the direction perpendicular to the substrate 10, the distance D1 between the red light-emitting layer 14 and the reflective surface 112 of the anode 111 is greater than the distance D2 between the green light-emitting layer 13 and the reflective surface 112 of the anode 111, and the distance between the green light-emitting layer 13 and the reflective surface 112 of the anode 111 is greater than the distance D3 between the blue light-emitting layer 12 and the reflective surface 112 of the anode 111.

[0073] It can be understood that by adjusting the length of the microcavity between the cathode and the anode 111, the light in the corresponding sub-pixel area can be selected and amplified, for example: the microcavity length in the red sub-pixel area matches the wavelength of the light emitted by the red light-emitting layer 14, thereby amplifying the red light and suppressing the green light and the blue light; the microcavity length in the green sub-pixel area matches the wavelength of the light emitted by the green light-emitting layer 13, thereby amplifying the green light and suppressing the red light and the blue light; the microcavity length in the blue sub-pixel area matches the wavelength of the light emitted by the blue light-emitting layer 12, thereby amplifying the blue light and suppressing the red light and the green light.

[0074] It should be noted that, since the wavelength of red light is greater than that of green light, the wavelength of green light is greater than that of blue light, and there is a corresponding relationship between the wavelength of light and the microcavity length (for example, there is an integer multiple relationship between the microcavity length and half of the wavelength of light), if the red light-emitting layer 14, the green light-emitting layer 13 and the blue light-emitting layer 12 are located at the same height in the direction perpendicular to the base substrate 10, the distance between each light-emitting layer and the reflective surface 112 of the anode 111 can be set as in the relevant technology, that is, the microcavity length of the red sub-pixel area 16 is greater than the microcavity length of the green sub-pixel area 17, and the microcavity length of the green sub-pixel area 17 is greater than the microcavity length of the blue sub-pixel.

[0075] However, in a device that realizes RGB full-color light emission, the light-emitting device structure of each sub-pixel area in the RGB pixel is the same, and all include light-emitting layers of multiple colors. The light of a specific wavelength is selected and amplified by adjusting the thickness of the anode layer 11. In this case, in a direction perpendicular to the substrate 10, if each light-emitting layer is located at different heights, for example, Figure 1 Neutralization Figure 2In the embodiment, the red light-emitting layer and the green light-emitting layer are far from the surface of the anode 111, and the blue light-emitting layer is close to the surface of the anode 111. If the distance between each light-emitting layer and the reflective surface 112 of the anode 111 is still set according to the distance between the light-emitting layers in the related art and the reflective surface 112, the length of the microcavity in the blue sub-pixel area 18 will not meet the actual demand (for example, the length of the microcavity in the blue sub-pixel area 18 in the related art is less than the microcavity required in the actual demand), which will cause the microcavity in the blue sub-pixel area 18 to have poor suppression effect on red light and / or green light when gaining blue light. In view of this, an embodiment of the present disclosure provides a display panel, which selects and gains light of a specific wavelength in each sub-pixel area by forming a microcavity between the reflective surface of the first electrode and the second electrode layer, so that different sub-pixel areas emit light of different colors. Since the light emission wavelength of the first light emitting layer is smaller than the light emission wavelength of the second light emitting layer, and the first light emitting layer is closer to the substrate than the second light emitting layer, in order to avoid the problem that the microcavity length of the first sub-pixel area cannot meet the actual needs, the present disclosure increases the microcavity length in the first sub-pixel area, that is, the first distance is greater than the second distance and the first distance is greater than the third distance, so that the microcavity in the first sub-pixel area can gain the light emitted by the first light emitting layer while effectively suppressing the light emitted by the second light emitting layer, thereby improving the light extraction efficiency of the first sub-pixel area.

[0076] Figure 3 A schematic diagram of a first partial cross-sectional structure of a display panel according to an embodiment of the present disclosure is shown; Figure 4 A second partial cross-sectional structural schematic diagram of the display panel according to an embodiment of the present disclosure is shown.

[0077] It should be noted that in order to make the structure of the partial cross section of the display panel more complete, Figure 3 The structure of the organic light-emitting functional layer is simplified and Figure 4 The various film layers in the organic light-emitting functional layer are shown in detail.

[0078] A first aspect of the present disclosure provides a display panel, including: a base substrate 20 , a first electrode layer 24 , a first light-emitting layer 25 , a second light-emitting layer 26 and a second electrode layer 27 .

[0079] The base substrate 20 includes a plurality of pixel units arranged in an array, the pixel units include a plurality of sub-pixel areas, the plurality of sub-pixel areas include a first sub-pixel area 21, a second sub-pixel area 22 and a third sub-pixel area 23; a first electrode layer 24 is arranged on one side of the base substrate 20, the first electrode layer 24 includes a plurality of first electrodes 241 arranged at intervals, the orthographic projection of the first electrode 241 on the base substrate 20 is at least partially located in the sub-pixel area, and the first electrode 241 has a reflective surface; a first light-emitting layer 25 is arranged on a side of the first electrode layer 24 away from the base substrate 20, the orthographic projection of the first light-emitting layer 25 on the base substrate 20 is at least partially located in the plurality of sub-pixel areas, and the light-emitting color of the first light-emitting layer 25 is substantially the same as the light-emitting color of the first sub-pixel area 21; a second light-emitting layer 26 is arranged on a side of the first light-emitting layer 25 away from the base substrate 20 On one side of the substrate 20, the orthographic projection of the second light-emitting layer 26 on the substrate 20 is at least partially located in the multiple sub-pixel areas, and the light-emitting wavelength of the second light-emitting layer 26 is greater than the light-emitting wavelength of the first light-emitting layer 25; the second electrode layer 27 is arranged on the side of the second light-emitting layer 26 away from the substrate 20, and the second electrode layer 27 has the characteristics of partial transmission and partial reflection; wherein, along the direction perpendicular to the substrate 20, the distance between the first light-emitting layer 25 of the first sub-pixel area 21 and the reflecting surface is a first distance L1, the distance between the first light-emitting layer 25 of the second sub-pixel area 22 and the reflecting surface is a second distance L2, and the distance between the first light-emitting layer 25 of the third sub-pixel area 23 and the reflecting surface is a third distance L3, the first distance is greater than the second distance L2, and the first distance L1 is greater than the third distance L3.

[0080] It can be understood that, in some embodiments, the first electrode layer 24 can be an anode and the second electrode layer 27 can be a cathode; in some embodiments, the first electrode layer 24 can also be a cathode and the second electrode layer 27 is an anode. For ease of understanding, the embodiment of the present disclosure is described by taking the first electrode layer 24 as an anode layer and the second electrode layer 27 as a cathode as an example.

[0081] The first electrode layer 24 has a reflective surface, and the second electrode layer 27 has a partially transmissive and partially reflective characteristic (e.g., a semi-transmissive and semi-reflective characteristic, a 60% transmissive and 40% transmissive characteristic, etc.), thereby forming a microcavity between the reflective surface of the first electrode layer 24 and the second electrode layer 27 (between the anode and the cathode), and in a direction perpendicular to the substrate 20, the length of the microcavity is the distance between the reflective surface of the first electrode layer 24 and the second electrode layer 27. Thus, the light beam directly emitted by the first light-emitting layer 25 interferes with the light beam reflected at the interface of the first electrode layer 24 (or the second electrode layer 27), and the light beam directly emitted by the second light-emitting layer 26 interferes with the light beam reflected at the interface of the first electrode layer 24 (or the second electrode layer 27), and the microcavity between the first electrode layer 24 and the second electrode layer 27 can narrow the electroluminescent spectrum of the first light-emitting layer 25, or narrow the electroluminescent spectrum of the second light-emitting layer 26, thereby improving the color purity, so that each sub-pixel area emits light of different colors.

[0082] The orthographic projection of the first electrode 241 on the substrate 20 is at least partially located in the sub-pixel area. This may be that the orthographic projection area of ​​the first electrode 241 on the substrate 20 is larger than the area of ​​the sub-pixel area, or the orthographic projection of the first electrode 241 on the substrate 20 covers the sub-pixel area.

[0083] The orthographic projection of the first light-emitting layer 25 on the base substrate 20 is at least partially located in the multiple sub-pixel regions. This may be that: the orthographic projection area of ​​the first light-emitting layer 25 on the base substrate 20 is larger than the area of ​​the multiple sub-pixel regions, or the orthographic projection of the first light-emitting layer 25 on the base substrate 20 covers the multiple sub-pixel regions.

[0084] The orthographic projection of the second light-emitting layer 26 on the base substrate 20 is at least partially located in the multiple sub-pixel regions. This can be: the orthographic projection area of ​​the second light-emitting layer 26 on the base substrate 20 is larger than the area of ​​the multiple sub-pixel regions, or the orthographic projection of the second light-emitting layer 26 on the base substrate 20 covers the multiple sub-pixel regions.

[0085] It is understood that the commonly used white light OLED light emitting layer structure includes: a blue light emitting layer, a green light emitting layer and a red light emitting layer, wherein the wavelength of light emitted by the blue light emitting layer is smaller than the wavelength of light emitted by the green light emitting layer, and the wavelength of light emitted by the blue light emitting layer is smaller than the wavelength of light emitted by the red light emitting layer. For ease of understanding, the embodiment of the present disclosure takes the first light emitting layer 25 configured to emit blue light and the second light emitting layer 26 configured to emit green light and red light as an example for explanation below.

[0086] It can be understood that when the first light-emitting layer 25 is configured to emit blue light, the first sub-pixel area 21 can be configured to emit blue light, that is, the first sub-pixel area 21 can be a blue sub-pixel area; when the second light-emitting layer 26 is configured to emit green light and red light, the second sub-pixel area 22 can be configured to emit green light, that is, the second sub-pixel area 22 can be a green sub-pixel area, and the third sub-pixel area 23 can be configured to emit red light, that is, the third sub-pixel area 23 can be a red sub-pixel area.

[0087] It should be noted that, although the microcavity of each sub-pixel region can play a role in gaining the color light emitted from the sub-pixel region and suppressing other color lights, for example, the microcavity of the blue sub-pixel region can gain blue light and suppress red light and green light. Ideally, the blue sub-pixel region only emits blue light, but in actual situations, the blue sub-pixel region may not be able to completely suppress red light and / or green light, and the blue sub-pixel region may emit a small amount of green light and / or blue light. Therefore, the light color of the first light-emitting layer 25 (for example, the blue light-emitting layer) in the embodiment of the present disclosure is substantially the same as the light color of the first sub-pixel region 21 (for example, the blue sub-pixel region).

[0088] In some embodiments, in a direction perpendicular to the base substrate 20 , the distance between the first light emitting layer 25 and the second electrode layer 27 of each of the sub-pixel regions is substantially the same.

[0089] It is understood that a plurality of pixels arranged in an array are generally provided on the base substrate 20. In the embodiment of the present disclosure, each of the pixels may include the first sub-pixel region 21, the second sub-pixel region 22, and the third sub-pixel region 23. Then, for the same pixel, the structures of the first light-emitting layer 25, the second light-emitting layer 26, and the second electrode layer 27 of the first sub-pixel region 21, the second sub-pixel region 22, and the third sub-pixel region 23 may be the same. That is, in the direction perpendicular to the base substrate 20, the first light-emitting layer 25 in each sub-pixel region is substantially at the same height, and the second light-emitting layer 26 in each sub-pixel region is substantially at the same height. In addition, the first anodes of the first sub-pixel region 21, the second sub-pixel region 22, and the third sub-pixel region 23 may be different.

[0090] In some embodiments, the second anode layer may include multiple independent second electrodes 271 , each second electrode 271 is electrically connected to a corresponding first electrode 241 , or the second anode layer may include a whole layer of second electrodes 271 , and the second electrode 271 is electrically connected to each of the first electrodes 241 .

[0091] It can be understood that, when the first light-emitting layer 25, the second light-emitting layer 26, and the second anode layer of each sub-pixel region are substantially the same, the distance from the first light-emitting layer 25 of each sub-pixel region to the reflective surface of the first electrode 241 determines the microcavity length of each sub-pixel region. Then, when the first distance is greater than the second distance L2, and the first distance L1 is greater than the third distance L3, the microcavity length H1 of the first sub-pixel region 21 is greater than the microcavity length H2 of the second sub-pixel region 22, and the microcavity length H1 of the first sub-pixel region 21 is greater than the microcavity length H3 of the third sub-pixel region 23. Since the light emission color of the first sub-pixel area 21 is substantially the same as the light emission color of the first light-emitting layer 25, the first light-emitting layer 25 is closer to the base substrate 20 than the second light-emitting layer 26, and the light emission wavelength of the first light-emitting layer 25 is smaller than the light emission wavelength of the second light-emitting layer 26. That is to say, the embodiment of the present disclosure increases the microcavity length of the sub-pixel area with a smaller light emission wavelength, thereby meeting the actual requirements of the first sub-pixel area 21 for the microcavity length, so that the microcavity length of the first sub-pixel area 21 can gain the light emitted by the first light-emitting layer 25 while effectively suppressing the light emitted by the second light-emitting layer 26, thereby improving the light extraction efficiency of the first sub-pixel area 21.

[0092] Figure 5 A third partial cross-sectional structural schematic diagram of the display panel according to an embodiment of the present disclosure is shown.

[0093] In some embodiments, in a direction perpendicular to the base substrate 20, the thickness of the first electrode 241 of the first sub-pixel region 21 is greater than the thickness of the first electrode 241 of the second sub-pixel region 22, and the thickness of the first electrode 241 of the first sub-pixel region 21 is greater than the thickness of the first electrode 241 of the third sub-pixel region 23.

[0094] Based on the above, it can be known that, in the case where the structures of the first light-emitting layer 25, the second light-emitting layer 26, and the second electrode layer 27 in each sub-pixel region are substantially the same, the distance from the first light-emitting layer 25 to the reflective surface of the first electrode 241 can be determined by the thickness of the first electrode 241. Then, in the case where the thickness S1 of the first electrode 241 in the first sub-pixel region 21 is greater than the thickness S2 of the first electrode 241 in the second sub-pixel region 22, and the thickness S1 of the first electrode 241 in the first sub-pixel region 21 is greater than the thickness S3 of the first electrode 241 in the third sub-pixel region 23, the first distance L1 can be greater than the second distance L2, and the first distance L1 can be greater than the third distance L3.

[0095] Figure 6 A schematic diagram of a partial cross-sectional structure of the first electrode layer 24 according to an embodiment of the present disclosure is shown.

[0096] In some embodiments, the first electrode 241 includes a reflective layer 241A, an adjustment layer 241B, and a conductive layer 241C. The reflective layer 241A is disposed on one side of the base substrate 20, and the side of the reflective layer 241A away from the base substrate 20 is the reflective surface; the adjustment layer 241B is disposed on the side of the reflective layer 241A away from the base substrate 20, and the adjustment layer 241B includes a via hole; the conductive layer 241C is disposed on the side of the adjustment layer 241B away from the base substrate 20, and is electrically connected to the reflective layer 241A through the via hole; in a direction perpendicular to the base substrate 20, the thickness G1 of the adjustment layer 241B in the first sub-pixel region 21 is greater than the thickness G2 of the adjustment layer 241B in the second sub-pixel region 22, and the thickness G1 of the adjustment layer 241B in the first sub-pixel region 21 is greater than the thickness G3 of the adjustment layer 241B in the third sub-pixel region 23.

[0097] Exemplarily, the reflective layer 241A has conductivity and opacity, and the reflective layer 241A may be a metal single substance layer or a metal alloy layer, for example, may include one or more of Mg (magnesium), Al (aluminum), and Ag (silver). Thus, the light emitted by the first light-emitting layer 25 or the light emitted by the second light-emitting layer 26 may be reflected on the reflective surface of the reflective layer 241A, and generate strong interference with the light directly emitted by the first light-emitting layer 25, thereby obtaining gain.

[0098] Exemplarily, the adjustment layer 241B is an inorganic layer with insulating properties, and the adjustment layer 241B may include at least two of the three elements Si (silicon), N (nitrogen), and O (oxygen). Thus, the microcavity length of each sub-pixel region can be adjusted by only setting the thickness of the adjustment layer 241B, simplifying the process flow and improving the process efficiency.

[0099] Exemplarily, the conductive layer 241C may be a conductive compound, such as a conductive metal oxide material, including indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), aluminum zinc oxide (AZO), etc. Thus, the conductive performance of the first anode layer is ensured by the electrical connection between the conductive layer 241C and the reflective layer 241A.

[0100] In some embodiments, the light emission wavelength of the second sub-pixel region 22 is smaller than the light emission wavelength of the third sub-pixel region 23 , and the thickness of the adjustment layer 241B of the second sub-pixel region 22 is smaller than the thickness of the adjustment layer 241B of the third sub-pixel region 23 .

[0101] For example: the first sub-pixel area 21 is a blue sub-pixel area, the second sub-pixel area 22 is a green sub-pixel area, and the third sub-pixel area 23 is a red sub-pixel area. The thickness of the adjustment layer 241B in the blue sub-pixel area is greater than the thickness of the adjustment layer 241B in the green sub-pixel area, the thickness of the adjustment layer 241B in the blue sub-pixel area is greater than the thickness of the adjustment layer 241B in the red sub-pixel area, and the thickness of the adjustment layer 241B in the green sub-pixel area is less than the thickness of the adjustment layer 241B in the red sub-pixel area.

[0102] In some embodiments, the thickness of the adjustment layer 241B of the first sub-pixel region 21 ranges from 1300 angstroms to 1600 angstroms, for example, 1300 angstroms, 1350 angstroms, 1400 angstroms, 1450 angstroms, 1500 angstroms, 1550 angstroms, 1600 angstroms, etc.

[0103] The thickness of the adjustment layer 241B of the second sub-pixel region 22 ranges from 300 angstroms to 600 angstroms, for example, 300 angstroms, 350 angstroms, 400 angstroms, 450 angstroms, 500 angstroms, 550 angstroms, 600 angstroms, etc.

[0104] The thickness of the adjustment layer 241B of the third sub-pixel region 23 ranges from 1200 angstroms to 1500 angstroms, for example, 1200 angstroms, 1250 angstroms, 1300 angstroms, 1350 angstroms, 1400 angstroms, 1450 angstroms, 1500 angstroms, etc.

[0105] It should be noted that there is an intersection between the thickness value range of the adjustment layer 241B of the first sub-pixel area 21 and the thickness value range of the adjustment layer 241B of the third sub-pixel area 23. Since the thickness of the adjustment layer 241B of the first sub-pixel area 21 is greater than the thickness of the adjustment layer 241B of the third sub-pixel area 23, when the thickness of the adjustment layer 241B of the two sub-pixel areas is determined, it is necessary to satisfy the relationship that the thickness of the adjustment layer 241B of the first sub-pixel area 21 is greater than the thickness of the adjustment layer 241B of the third sub-pixel area 23. For example, when the thickness of the adjustment layer 241B of the first sub-pixel area 21 is 1300 angstroms, the thickness of the adjustment layer 241B of the third sub-pixel area 23 may be 1200 angstroms. When the thickness of the adjustment layer 241B of the first sub-pixel area 21 is 1500 angstroms, the thickness of the adjustment layer 241B of the third sub-pixel area 23 may be 1400 angstroms.

[0106] In some embodiments, the thickness of the adjustment layer 241B in each of the sub-pixel regions is different, the thickness of the conductive layer 241C in each of the sub-pixel regions is substantially the same, and the thickness of the reflective layer 241A in each of the sub-pixel regions is substantially the same.

[0107] It should be noted that, since a driving circuit layer (not shown) is usually provided between the entire first electrode layer 24 and the base substrate 20, the driving circuit needs to be electrically connected to the first electrode layer 24, so it is necessary to connect the reflective layer 241A and the conductive layer 241C through vias. By setting the thickness of the adjustment layer 241B in each sub-pixel area to be different, the microcavity lengths of each sub-pixel area are different. For example: the thickness G1 of the adjustment layer 241B of the first sub-pixel area 21 is greater than the thickness G2 of the adjustment layer 241B of the second sub-pixel area 22, and the thickness G1 of the adjustment layer 241B of the first sub-pixel area 21 is greater than the thickness G3 of the adjustment layer 241B of the third sub-pixel area 23.

[0108] In some embodiments, in a direction perpendicular to the base substrate 20, the thickness of the adjustment layer 241B is greater than the thickness of the conductive layer 241C. The thickness of the adjustment layer 241B in the first sub-pixel region 21 is greater than the thickness of the reflective layer 241A, the thickness of the adjustment layer 241B in the second sub-pixel region 22 is less than the thickness of the reflective layer 241A, and the thickness of the adjustment layer 241B in the third sub-pixel region 23 is greater than the thickness of the reflective layer 241A.

[0109] It is understandable that if the adjustment layer 241B is set as a conductive film layer, it may cause the conductivity of the first electrode 241 to change, thereby damaging the device performance. Therefore, in order to reduce the resistance of the first electrode 241 and improve the conductivity, the adjustment layer 241B is set as an inorganic layer (insulating layer), which can have a small impact on the conductivity of the first electrode 241. In addition, the microcavity length of each sub-pixel area is determined only by setting the thickness of the adjustment layer 241B, so that the first light-emitting layer 25, the second light-emitting layer 26, the second electrode layer 27, the conductive layer 241C and the reflective layer 241A in each sub-pixel area can all adopt the same structure, thereby simplifying the process and improving the process efficiency.

[0110] In some embodiments, the microcavity length of each sub-pixel region may be set by setting the height of the conductive layer 241C and / or the reflective layer 241A, which is not limited here.

[0111] In some embodiments, the second light emitting layer 26 is configured to emit a first light and a second light, the color of the first light is substantially the same as the light emitting color of the second sub-pixel area 22, the color of the second light is substantially the same as the light emitting color of the third sub-pixel area 23, and the emission wavelength of the first light is smaller than the emission wavelength of the second light.

[0112] It is understandable that, in the preparation process, the second light-emitting layer 26 can be prepared by using a mixed first light-emitting material and a second light-emitting material, such as a red light-emitting material and a green light-emitting material. Thus, the second light-emitting layer 26 can emit both red light and green light, and the selection and gain of red light or green light can be achieved later by different microcavity lengths of each sub-pixel region, for example: the microcavity length of the second sub-pixel region 22 matches the wavelength of green light, so that the light color of the second sub-pixel region 22 is green, and the microcavity length of the third sub-pixel region 23 matches the wavelength of red light, so that the light color of the third sub-pixel region 23 is red.

[0113] In some embodiments, the second light emitting layer 26 includes:

[0114] A first sub-light emitting layer 26A is disposed on a side of the first light emitting layer 25 away from the base substrate 20, and an orthographic projection of the first sub-light emitting layer 26A on the base substrate 20 is at least partially located in the plurality of sub-pixel regions. The first sub-light emitting layer 26A is configured to emit a first light, and a color of the first light is substantially the same as a color of light emitted from the second sub-pixel region 22;

[0115] The second sub-light emitting layer 26B is arranged on the side of the first sub-light emitting layer 26A away from the base substrate 20, and the orthographic projection of the second sub-light emitting layer 26B on the base substrate 20 is at least partially located in the multiple sub-pixel areas. The second sub-light emitting layer 26B is configured to emit a second light, and the color of the second light is basically the same as the light emission color of the third sub-pixel area 23, and the emission wavelength of the first light is smaller than the emission wavelength of the second light.

[0116] For example, the first sub-light emitting layer 26A is configured to emit green light, and the second sub-pixel region 22 is configured to emit green light; the second sub-light emitting layer 26B is configured to emit red light, and the third sub-pixel region 23 is configured to emit red light.

[0117] The orthographic projection of the first sub-light-emitting layer 26A on the base substrate 20 is at least partially located in the multiple sub-pixel regions. This can be: the orthographic projection area of ​​the first sub-light-emitting layer 26A on the base substrate 20 is larger than the area of ​​the multiple sub-pixel regions, or the orthographic projection of the first sub-light-emitting layer 26A on the base substrate 20 covers the multiple sub-pixel regions.

[0118] The orthographic projection of the second sub-light-emitting layer 26B on the base substrate 20 is at least partially located in the multiple sub-pixel regions. This may be that: the orthographic projection area of ​​the second sub-light-emitting layer 26B on the base substrate 20 is larger than the area of ​​the multiple sub-pixel regions, or the orthographic projection of the second sub-light-emitting layer 26B on the base substrate 20 covers the multiple sub-pixel regions.

[0119] It should be noted that, although the microcavity of each sub-pixel area can play a role in gaining the color light emitted from the sub-pixel area and suppressing other color lights, for example, the microcavity of the green sub-pixel area can gain green light and suppress red light and blue light. Ideally, the green sub-pixel area only emits green light, but in actual situations, the green sub-pixel area may not be able to completely suppress red light and / or blue light, and the green sub-pixel area may emit a small amount of red light and / or blue light. Therefore, taking the first sub-light emitting layer 26A as a green light emitting layer, the second sub-pixel area 22 as a green sub-pixel area, the second sub-light emitting layer 26B as a red light emitting layer, and the third sub-pixel area 23 as a red sub-pixel area as an example, the color of the first light is substantially the same as the color of the light emitted from the second sub-pixel area 22, and the color of the second light is substantially the same as the color of the light emitted from the third sub-pixel area 23.

[0120] Figure 7 A fourth partial cross-sectional structural schematic diagram of the display panel according to an embodiment of the present disclosure is shown.

[0121] In some embodiments, in a direction perpendicular to the base substrate 20, there is a fourth distance L4 between the first sub-light emitting layer 26A of the second sub-pixel region 22 and the reflective surface, there is a fifth distance L5 between the second sub-light emitting layer 26B of the third sub-pixel region 23 and the reflective surface, the fifth distance L5 is greater than the fourth distance L4, the fifth distance L5 is greater than the first distance L1, and the fourth distance L4 is less than the first distance L1.

[0122] It can be understood that, in the direction perpendicular to the base substrate 20, the distance between the lower surface of the first light-emitting layer 25 of the first sub-pixel region 21 and the reflective surface is L1, the distance between the lower surface of the first sub-light-emitting layer 26A of the second sub-pixel region 22 and the reflective surface is a fourth distance L4, and there is a fifth distance L5 between the second sub-light-emitting layer 26B of the third sub-pixel region 23 and the reflective surface. By setting the thickness of the adjustment layer 241B of each sub-pixel region, the light-emitting layer in each sub-pixel region and the anode reflective surface have the above-mentioned distance relationship, so that the microcavity length of each sub-pixel region meets the requirements.

[0123] In some embodiments, the first distance ranges from 1500 angstroms to 2000 angstroms, for example, 1500 angstroms, 1550 angstroms, 1600 angstroms, 1650 angstroms, 1700 angstroms, 1750 angstroms, 1800 angstroms, 1850 angstroms, 1900 angstroms, 1950 angstroms, 2000 angstroms, etc.

[0124] The value range of the fourth distance is: 1500 angstroms-2000 angstroms, for example, 1500 angstroms, 1550 angstroms, 1600 angstroms, 1650 angstroms, 1700 angstroms, 1750 angstroms, 1800 angstroms, 1850 angstroms, 1900 angstroms, 1950 angstroms, 2000 angstroms, etc.

[0125] The value range of the fifth distance is: 2250 angstroms-2750 angstroms, for example, 2250 angstroms, 2300 angstroms, 2350 angstroms, 2400 angstroms, 2450 angstroms, 2500 angstroms, 2550 angstroms, 2600 angstroms, 2650 angstroms, 2700 angstroms, 2750 angstroms, etc.

[0126] It should be noted that there is an overlap between the values ​​of the first distance and the fourth distance. When the values ​​of the first distance and the fourth distance are specifically taken, the distance relationship that the fourth distance L4 is smaller than the first distance L1 still needs to be satisfied.

[0127] In some embodiments, along a direction perpendicular to the base substrate 20, the distance between the reflective surface and the second electrode layer 27 is the microcavity length; the ratio of the microcavity length H1 of the first sub-pixel area 21 to half of the emission wavelength of the first light-emitting layer 25 is N1, the ratio of the microcavity length H2 of the second sub-pixel area 22 to half of the emission wavelength of the first sub-light-emitting layer 26A is N2, and the ratio of the microcavity length H3 of the third sub-pixel area 23 to half of the emission wavelength of the second sub-light-emitting layer 26B is N3, wherein N1, N2 and N3 are positive integers, N1 is greater than N2 and N1 is greater than N3.

[0128] It should be noted that the matching relationship between the microcavity length and the wavelength can determine what wavelength of light can form a standing wave in the microcavity. For example, for a linear microcavity, the key to light forming a standing wave in the microcavity is to meet the following conditions:

[0129]

[0130] Where L is the length of the microcavity, m is a positive integer (mode order), which is the number of half wavelengths; λ eff represents the effective wavelength of light in the medium, and the medium in the embodiment of the present disclosure is the reflective surface of the first electrode layer 24 and each film layer between the second electrode layer 27. It can be seen from the formula that in order to form a standing wave in the microcavity, the length of the microcavity needs to be an integer multiple of half the wavelength of light.

[0131] The following example takes the first sub-pixel region 21 as a blue sub-pixel region, the second sub-pixel region 22 as a green sub-pixel region, the third sub-pixel region 23 as a red sub-pixel region, the first light-emitting layer 25 as a blue light-emitting layer, the first sub-light-emitting layer 26A as a green light-emitting layer, and the second sub-light-emitting layer 26B as a blue light-emitting layer.

[0132] In the related art, it is assumed that the ratio of the microcavity length of the red sub-pixel area to half of the red light wavelength is 10, the ratio of the microcavity length of the green sub-pixel area to half of the red light wavelength is 10, and the ratio of the microcavity length of the blue sub-pixel area to half of the blue light wavelength is 10. In the above ratio relationship, since the blue light-emitting layer is closer to the substrate 20 than the green light-emitting layer and the red light-emitting layer, the microcavity length of the blue sub-pixel area cannot effectively suppress red light and / or green light except for gaining the blue light wavelength, resulting in poor light extraction efficiency of the blue sub-pixel area.

[0133] In the embodiment of the present disclosure, it is assumed that the ratio of the microcavity length of the red sub-pixel region to half the wavelength of red light is 10, the ratio of the microcavity length of the green sub-pixel region to half the wavelength of red light is 10, and the ratio of the microcavity length of the blue sub-pixel region to half the wavelength of blue light is 20. In the above ratio relationship, by increasing the microcavity length of the blue sub-pixel region, on the one hand, the microcavity length of the blue sub-pixel region can still satisfy the integer multiple relationship with half the wavelength of blue light, and on the other hand, the microcavity length of the blue sub-pixel region deviates further from the integer multiple relationship with half the wavelength of red light and / or half the wavelength of green light, so that the blue light wavelength can be gained while effectively suppressing red light and / or green light, thereby improving the light extraction efficiency of the blue sub-pixel region.

[0134] It is understandable that the above examples of ratio relationships are only for ease of understanding and do not constitute a limitation on the embodiments of the present disclosure.

[0135] In some embodiments, the display panel further includes: a hole injection layer 31, a first hole transport layer 32, a first electron transport layer 33, an N (Negtive, negative) type charge transport layer 34, a P (Positive, positive) type charge transport layer 35, a second hole transport layer 36, and a second electron transport layer 37, which are sequentially stacked on the side of the first light-emitting layer 25 away from the base substrate 20. Among them, the hole injection layer 31 is arranged on one side of the base substrate 20; the first hole transport layer 32 is arranged on the side of the hole injection layer 31 away from the base substrate 20, and is arranged on the side of the first light-emitting layer 25 close to the base substrate 20; the second hole transport layer 36 is arranged on the side of the first sub-light-emitting layer 26A close to the base substrate 20; the second electron transport layer 37 is arranged on the side of the second sub-light-emitting layer 26B away from the base substrate 20.

[0136] It is understandable that the principles and structures of the various organic functional layers of the above-mentioned light-emitting device can be referred to in the relevant technology and will not be described in detail here.

[0137] In some embodiments, a first electron blocking layer (not shown) is provided between the first hole transport layer 32 and the first light-emitting layer 25, and / or a second electron blocking layer (not shown) is provided between the second hole transport layer 36 and the first sub-light-emitting layer 26A.

[0138] In some embodiments, a first hole blocking layer (not shown) is disposed between the first electron transport layer 33 and the first light-emitting layer 25, and / or a second hole blocking layer (not shown) is disposed between the second electron transport layer 37 and the second sub-light-emitting layer 26B.

[0139] It should be noted that, since the electron transport materials in organic light-emitting diode devices are mostly metal oxides such as ZnO (zinc oxide) and ZnMgO (zinc magnesium oxide), their electron mobility is high and the energy level matches the LUMO (Lowest Unoccupied Molecular Orbital) energy level of quantum dots, while the hole side is mostly organic hole injection and transport materials. The lower mobility of organic materials and the larger HOMO (Highest Occupied Molecular Orbital) energy level difference between them and quantum dots result in relatively poor hole injection in the device, and there are often excess electrons in the device. The thickness of the material film layer in the light-emitting device may affect the balance of carriers. For example, if the mobility or carrier transmission efficiency of a certain film layer in the light-emitting device is particularly high, then the thickness of the film layer of this material should be thickened, otherwise there will be an imbalance in carrier transmission. If the carriers in the light-emitting device are unbalanced, not only will the device efficiency be affected, but the excess charge will also charge the quantum dots, thereby reducing the device life.

[0140] Figure 8 A fifth partial cross-sectional structural schematic diagram of the display panel according to an embodiment of the present disclosure is shown.

[0141] In some embodiments, in a direction perpendicular to the base substrate 20, there is a sixth distance L6 between a side of the first light-emitting layer 25 close to the base substrate 20 and a side of the first electrode 241 away from the base substrate 20, there is a seventh distance L7 between a side of the first light-emitting layer 25 away from the base substrate 20 and a side of the first sub-light-emitting layer 26A close to the base substrate 20, and there is an eighth distance L8 between a side of the second sub-light-emitting layer 26B away from the base substrate 20 and a side of the second electrode layer 27 close to the base substrate 20; wherein the sixth distance L6 is greater than the eighth distance L8, and the eighth distance L8 is greater than the seventh distance L7.

[0142] It can be understood that, in the direction perpendicular to the base substrate 20, the superposition of the sixth distance L6, the seventh distance L7 and the eighth distance L8 is equivalent to the difference between the distance between the lower surface of the first electrode layer 24 and the upper surface of the second electrode layer 27 (conductive layer 241C) and the sum of the thicknesses of the various light-emitting layers. That is, based on the thickness of each light-emitting layer, the embodiment of the present disclosure takes into account the influence of the thickness of each material film layer in the light-emitting device on the balance of carriers, and establishes the above thickness relationship of each film layer, so that

[0143] This balances the carriers in the light-emitting device, improves the device efficiency, and increases the device life.

[0144] In some embodiments, the display panel further includes: a covering layer, an encapsulation layer 41 and a color filter layer.

[0145] The covering layer is arranged on a side of the second electrode layer 27 away from the base substrate 20 . The covering layer may be a single layer or multiple layers stacked together. The covering layer is configured to protect the second electrode layer 27 .

[0146] The encapsulation layer 41 is disposed on a side of the cover layer away from the base substrate 20 . The encapsulation layer 41 may be one side or multiple layers stacked, for example, including a first encapsulation layer 42 , a second encapsulation layer 43 and a third encapsulation layer 44 stacked.

[0147] The color filter layer is arranged on a side of the encapsulation layer 41 away from the base substrate 20, and includes a first color filter unit, a second color filter unit and a third color filter unit. The orthographic projection of the first color filter unit on the base substrate 20 substantially overlaps with the orthographic projection of the first sub-pixel area 21 on the base substrate 20. The first color filter unit is configured to filter light emitted from the first sub-pixel area 21 (for example, the first sub-pixel area 21 emits blue light, and the first color filter unit is configured to filter red light and green light).

[0148] The orthographic projection of the second color filter unit on the base substrate 20 is substantially overlapped with the orthographic projection of the second sub-pixel area 22 on the base substrate 20, and the second color filter unit is configured to filter the light emitted from the first sub-pixel area 21 (for example, the second sub-pixel area 22 emits green light, and the second color filter unit is configured to filter red light and blue light); the orthographic projection of the third color filter unit on the base substrate 20 is substantially overlapped with the orthographic projection of the third sub-pixel area 23 on the base substrate 20, and the third color filter unit is configured to filter the light emitted from the third sub-pixel area 23 (for example, the third sub-pixel area 23 emits red light, and the third color filter unit is configured to filter green light and blue light).

[0149] It is understandable that although the microcavity of each sub-pixel area can enhance and suppress colored light, for example, ideally, the first sub-pixel area 21 only emits blue light, but in actual situations, the microcavity of the first sub-pixel area 21 may not be able to suppress red light and / or green light by 100%. Therefore, a small amount of red light and / or green light may be doped in the light emitted by the first sub-pixel area 21. Therefore, the embodiment of the present disclosure further filters the light emitted by the sub-pixel area by setting a color filter layer to improve the light output efficiency.

[0150] In some embodiments, the display panel further comprises:

[0151] The pixel definition layer 38 is located on the side of the first electrode 241 away from the base substrate 20. The pixel definition layer 38 is provided with a plurality of openings, and the openings leak out at least a portion of the first electrode 241. An organic functional layer is provided between the first electrode layer 24 and the second electrode layer 27. The light-emitting region of the organic functional layer is located in the opening and in contact with the first electrode 241.

[0152] In some embodiments, the display panel further comprises:

[0153] A first isolation structure layer 39, disposed on a side of the pixel definition layer 38 away from the opening;

[0154] The second isolation structure layer 40 is arranged on the side of the first isolation structure layer 39 away from the pixel definition layer 38. The first isolation structure layer 39 and the second isolation structure layer 40 are configured to separate the organic functional layer between the anode layer and the cathode layer so that each sub-pixel area is isolated from each other.

[0155] An exemplary method for preparing the display panel according to an embodiment of the present disclosure is described below.

[0156] Step 1: An anode layer is formed on a glass substrate, and the glass substrate with the anode layer (eg, ITO (Indium Tin Oxide)) is ultrasonically treated in a cleaning agent, rinsed in deionized water, ultrasonically degreased in an acetone-ethanol mixed solvent, and baked in a clean environment until moisture is completely removed.

[0157] Step 2: Place the glass substrate with the anode layer in a vacuum chamber, evacuate to 1×10-5~1×10-6, and vacuum evaporate to form a hole injection layer 31HIL on the anode layer, wherein the evaporation ratio can be 97:3, and the thickness of the hole injection layer 31HIL can be 10nm.

[0158] Step 3: Form a first hole transport layer 32HTL-1 on the hole injection layer 31HIL by evaporation. The thickness of the first hole transport layer 32HTL-1 may be 10 nm.

[0159] Step 4: forming a first electron blocking layer EBL on the first hole transport layer 32HTL-1 by evaporation. The thickness of the first electron blocking layer EBL may be X nm.

[0160] Step 5: Using a multi-source co-evaporation method, vacuum evaporate and form a blue light-emitting layer on the first electron blocking layer EBL. The blue light-emitting layer may include a host material and a guest material. The thickness of the blue light-emitting layer may be 22 nm, and BH:BD=98:2.

[0161] Step 6: Form a first hole blocking layer HBL-1 by evaporation on the blue light-emitting layer. The thickness of the first hole blocking layer may be 5 nm.

[0162] Step 7: On the first hole blocking layer HBL-1, a BCP material and a Liq material are co-evaporated from dual sources, and the mass ratio of the BCP material to the Liq material may be 1:1, to form a first electron transport layer 33 .

[0163] Step 8: On the first electron transport layer 33, an N-type charge transport layer 34 (CGL: Li 1%) is formed by a multi-source co-evaporation method, and the thickness may be 10 nm.

[0164] Step 9: On the N-type charge transport layer 34, a P-type charge transport layer 35 (HTL: HIL 10%) is formed by a multi-source co-evaporation method, and the thickness may be 7 nm.

[0165] Step 10: Form a second hole transport layer 36 by evaporation on the P-type charge transport layer 35. The thickness of the second hole transport layer 36 may be Y nm.

[0166] Step 11: Form a second electron blocking layer on the second hole transport layer 36 by evaporation. The thickness of the second electron blocking layer may be 5 nm.

[0167] Step 12: on the second electron blocking layer, vacuum evaporate a red light-emitting layer by using a multi-source co-evaporation method, the red light-emitting layer includes a host material and a guest material, and the thickness of the red light-emitting layer can be 10 nm;

[0168] Step 13: A green light-emitting layer is formed by evaporation on the red light-emitting layer. The green light-emitting layer includes a host material and a guest material. The thickness of the green light-emitting layer can be 30 nm by using a multi-source co-evaporation method, and GH:GD=90:10.

[0169] Step 14: Form a second hole blocking layer by evaporation on the green light-emitting layer. The thickness of the second hole blocking layer may be 5 nm.

[0170] Step 15: BCP and Liq are co-evaporated from dual sources on the second hole blocking layer with a mass ratio of 1:1 and a thickness of Z nm to form a second electron transport layer 37 .

[0171] Step 16: Yb with a thickness of 1 nm is vacuum-evaporated on the second electron transport layer 37 as an electron injection layer.

[0172] Step 17: Dual-source co-evaporation of Mg and Al at a mass ratio of 8:2 is performed on the electron injection layer to form the cathode layer of the device.

[0173] Step 18: Evaporate CPL material on the cathode layer, the thickness can be 60nm.

[0174] Table 1

[0175]

[0176] It should be noted that X in Table 1 refers to the thickness of the first electron blocking layer, Y refers to the thickness of the second hole transport layer 36, Z refers to the thickness of the second electron transport layer 37, voltage refers to the operating voltage of the light-emitting device, EQE refers to External Quantum Efficiency, and the life of a chip model LT95@1000nit is used as an example for explanation.

[0177] It can be seen from Table 1 that when one or more of the thickness of the first electron blocking layer, the thickness of the second hole transport layer 36 and the thickness of the second electron transport layer 37 are different, one or more of the operating voltage, external electron efficiency and chip life of the light-emitting device will be different.

[0178] For example: Based on Examples 1-3, Comparative Examples 1 and 2 increase the thickness X of the first electron blocking layer. When the thickness X of the first electron blocking layer is too large, the distance L6 from the lower surface of the blue light-emitting layer to the upper surface of the anode will be greater than the distance L8 from the upper surface of the red light-emitting layer to the lower surface of the cathode layer, that is, L6>L8, thereby increasing the hole transmission path. It can be seen from the data in Table 1 that when the hole transmission path increases, the EQE decreases, the chip life is also reduced, and the performance of the light-emitting device is reduced.

[0179] For another example: Based on Examples 1, 4 and 5, Comparative Examples 3 and 4 reduce the thickness Y of the second hole transport layer 36. When the thickness Y of the second hole transport layer 36 is small, the distance L8 from the upper surface of the red light-emitting layer to the lower surface of the cathode layer will be greater than the distance L7 from the upper surface of the blue light-emitting layer to the lower surface of the green light-emitting layer, that is, L8>L7, which will cause the distance from the charge transport layer (N-type and P-type) to the red light-emitting layer and the green light-emitting layer to be too short, thereby causing electrons to accumulate in the red light-emitting layer and the green light-emitting layer toward the cathode layer. It can be seen from the data in Table 1 that when L8>L7, EQE is reduced, the chip life is also reduced, and the performance of the light-emitting device is reduced.

[0180] For another example: Based on Examples 1, 7 and 8, Comparative Examples 5 and 6 reduce the thickness Z of the second electron transport layer 37. When the thickness Z of the second electron transport layer 37 is small, the distance L6 from the lower surface of the blue light-emitting layer to the upper surface of the anode is greater than the distance L8 from the upper surface of the red light-emitting layer to the lower surface of the cathode layer, that is, L6>L8, thereby increasing the hole transport path. From the data in Table 1, it can be seen that when the hole transport path increases, the EQE decreases, thereby reducing the performance of the light-emitting device. However, compared with Comparative Examples 1 and 2, Comparative Examples 5 and 6 have a loss in EQE, but almost no loss in life, that is, when the thickness Z of the second electron transport layer 37 changes, it has almost no effect on the device life.

[0181] Based on Examples 1-8 and Comparative Examples 1-6 in Table 1, it can be verified that, in the direction perpendicular to the base substrate 20, there is a sixth distance L6 between the side of the first light-emitting layer 25 (blue light-emitting layer) close to the base substrate 20 and the side of the first electrode 241 (anode) away from the base substrate 20, there is a seventh distance L7 between the side of the first light-emitting layer 25 (blue light-emitting layer) away from the base substrate 20 and the side of the first sub-light-emitting layer 26A (green light-emitting layer) close to the base substrate 20, and there is an eighth distance L8 between the side of the second sub-light-emitting layer 26B (red light-emitting layer) away from the base substrate 20 and the side of the second electrode layer 27 (cathode layer) close to the base substrate 20; wherein the sixth distance L6 is greater than the eighth distance L8, and the eighth distance L8 is greater than the seventh distance L7, on this basis, it is possible to balance the carriers, ensure the external electron efficiency of the light-emitting device, and ensure the life of the light-emitting device.

[0182] For example, based on the thickness of the first electron blocking layer, the thickness of the second hole transport layer 36, and the thickness of the second electron transport layer 37 in Example 1 in Table 1, the organic light-emitting functional layer 45 and the cathode of the light-emitting device can be prepared. As shown in Table 2, the thickness values ​​of each film layer of one of the light-emitting devices are shown.

[0183] Table 2

[0184] First hole injection layer 100 Angstroms First hole transport layer 100 Angstroms The first electron blocking layer 50 Angstroms Blue light emitting layer 220 Angstroms First hole blocking layer 50 Angstroms First electron transport layer 100 Angstroms First charge generation layer 100 Angstroms Second charge generation layer 70 Angstroms Second hole transport layer 250 Angstroms The second electron blocking 50 Angstroms Red light emitting layer 100 Angstroms Green light emitting layer 300 Angstroms Second hole blocking layer 50 Angstroms Second electron transport layer 400 Angstroms Electron injection layer 10 Angstroms cathode 130 Angstroms

[0185] Exemplarily, based on the thickness values ​​of each film layer of the light-emitting device in Table 2, the thickness values ​​of the anode layer corresponding to each sub-pixel area of ​​the pixel are described.

[0186] Table 3

[0187]

[0188] According to the settings in the relevant technology, if the distance between the red light-emitting layer and the reflective surface is greater than the distance between the green light-emitting layer and the reflective surface, and the distance between the green light-emitting layer and the reflective surface is greater than the distance between the blue light-emitting layer and the reflective surface, it can be seen from Comparative Example 7 that the thickness of the adjustment layer 241B in the red sub-pixel area is 1300 angstroms, the thickness of the adjustment layer 241B in the blue sub-pixel area is 400 angstroms, the thickness of the adjustment layer 241B in the blue sub-pixel area is 300 angstroms, the microcavity length in the red sub-pixel area is 3300 angstroms, the microcavity length in the green sub-pixel area is 2400 angstroms, and the microcavity length in the blue sub-pixel area is 2300 angstroms. The microcavity length in the blue sub-pixel area is close to the microcavity length in the green sub-pixel area, so the green light suppression effect is poor.

[0189] In the disclosed embodiments, it can be seen from Embodiment 10 that the thickness of the adjustment layer 241B in the red sub-pixel region is 1300 angstroms, the thickness of the adjustment layer 241B in the blue sub-pixel region is 400 angstroms, the thickness of the adjustment layer 241B in the blue sub-pixel region is 1600 angstroms, the microcavity length in the red sub-pixel region is 3300 angstroms, the microcavity length in the green sub-pixel region is 2400 angstroms, and the microcavity length in the blue sub-pixel region is 3600 angstroms. The microcavity length in the blue sub-pixel region is significantly different from that in the green sub-pixel region, so that the microcavity length in the blue sub-pixel region and half of the wavelength of green light deviate further from the integer multiple relationship, thereby being able to enhance the suppression effect on green light.

[0190] It can be understood that the thickness of the adjustment layer 241B in the blue sub-pixel area of ​​the embodiment of the present disclosure is increased, which can also have a better suppression effect on red light. The specific setting can be based on actual product requirements and will not be repeated here.

[0191] Fig. 9 A structural block diagram of a display device according to an embodiment of the present disclosure is shown.

[0192] A second aspect of the embodiments of the present disclosure provides a display device 300 , comprising a display panel 200 as described in any one of the first aspects.

[0193] The display device 300 may be any product or component with a display function, such as a mobile phone, a tablet computer, a television, a monitor, a notebook computer, a digital photo frame, a navigator, or the like.

[0194] It should be noted that the above embodiments illustrate the present invention rather than limit it, and that those skilled in the art may devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference symbol between brackets shall not be construed as a limitation on the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "one" or "an" preceding an element does not exclude the presence of a plurality of such elements. The present invention may be implemented by means of hardware comprising a number of different elements and by means of a suitably programmed computer. In a unit claim enumerating a number of devices, several of these devices may be embodied by the same hardware item. The use of the words first, second, and third, etc., does not indicate any order. These words may be interpreted as names.

[0195] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A display panel, characterized in that: include: A substrate, comprising a plurality of sub-pixel regions, wherein the plurality of sub-pixel regions include a first sub-pixel region, a second sub-pixel region and a third sub-pixel region; A first electrode layer is arranged on one side of the base substrate, the first electrode layer comprises a plurality of first electrodes arranged at intervals, the orthographic projections of the first electrodes on the base substrate are at least partially located in the sub-pixel area, and the first electrodes have a reflective surface; A first light-emitting layer is arranged on a side of the first electrode layer away from the base substrate, the orthographic projection of the first light-emitting layer on the base substrate is at least partially located in the plurality of sub-pixel regions, and the light emission color of the first light-emitting layer is substantially the same as the light emission color of the first sub-pixel region; A second light-emitting layer is arranged on a side of the first light-emitting layer away from the base substrate, the orthographic projection of the second light-emitting layer on the base substrate is at least partially located in the plurality of sub-pixel regions, and the light emission wavelength of the second light-emitting layer is greater than the light emission wavelength of the first light-emitting layer; A second electrode layer is arranged on a side of the second light-emitting layer away from the base substrate; Among them, along the direction perpendicular to the base substrate, the distance between the first light-emitting layer and the reflective surface of the first sub-pixel area is a first distance, the distance between the first light-emitting layer and the reflective surface of the second sub-pixel area is a second distance, and the distance between the first light-emitting layer and the reflective surface of the third sub-pixel area is a third distance, the first distance is greater than the second distance, and the first distance is greater than the third distance.

2. The display panel according to claim 1, characterized in that: In a direction perpendicular to the base substrate, a thickness of the first electrode in the first sub-pixel region is greater than a thickness of the first electrode in the second sub-pixel region, and a thickness of the first electrode in the first sub-pixel region is greater than a thickness of the first electrode in the third sub-pixel region.

3. The display panel according to claim 1, characterized in that: The first electrode comprises: A reflective layer, arranged on one side of the base substrate, wherein a side of the reflective layer away from the base substrate is the reflective surface; An adjustment layer, disposed on a side of the reflective layer away from the base substrate, the adjustment layer comprising a via hole; A conductive layer, disposed on a side of the adjustment layer away from the base substrate, and electrically connected to the reflective layer through the via hole; In a direction perpendicular to the base substrate, the thickness of the adjustment layer in the first sub-pixel region is greater than the thickness of the adjustment layer in the second sub-pixel region, and the thickness of the adjustment layer in the first sub-pixel region is greater than the thickness of the adjustment layer in the third sub-pixel region.

4. The display panel according to claim 3, characterized in that: The light emission wavelength of the second sub-pixel region is smaller than the light emission wavelength of the third sub-pixel region, and the thickness of the adjustment layer in the second sub-pixel region is smaller than the thickness of the adjustment layer in the third sub-pixel region.

5. The display panel according to claim 3, characterized in that: The thickness of the adjustment layer in the first sub-pixel region ranges from 1300 angstroms to 1600 angstroms; The thickness of the adjustment layer in the second sub-pixel region ranges from 300 angstroms to 600 angstroms; The thickness of the adjustment layer in the third sub-pixel region ranges from 1200 angstroms to 1500 angstroms.

6. The display panel according to claim 3, characterized in that: The thickness of the adjustment layer in each of the sub-pixel regions is different, the thickness of the conductive layer in each of the sub-pixel regions is substantially the same, and the thickness of the reflective layer in each of the sub-pixel regions is substantially the same.

7. The display panel according to claim 1, characterized in that: The second light-emitting layer is configured to emit a first light and a second light, the color of the first light is substantially the same as the light color of the second sub-pixel area, the color of the second light is substantially the same as the light color of the third sub-pixel area, and the light emission wavelength of the first light is smaller than the light emission wavelength of the second light.

8. The display panel according to claim 1, characterized in that: The second light-emitting layer comprises: A first sub-light emitting layer is disposed on a side of the first light emitting layer away from the base substrate, an orthographic projection of the first sub-light emitting layer on the base substrate is at least partially located in the plurality of sub-pixel regions, the first sub-light emitting layer is configured to emit a first light, and a color of the first light is substantially the same as a color of light emitted from the second sub-pixel region; The second sub-light emitting layer is arranged on a side of the first sub-light emitting layer away from the base substrate, and the orthographic projection of the second sub-light emitting layer on the base substrate is at least partially located in the multiple sub-pixel areas. The second sub-light emitting layer is configured to emit a second light, and the color of the second light is basically the same as the light emission color of the third sub-pixel area, and the emission wavelength of the first light is smaller than the emission wavelength of the second light.

9. The display panel according to claim 8, characterized in that: In a direction perpendicular to the base substrate, a fourth distance exists between the first sub-light emitting layer in the second sub-pixel region and the reflective surface, a fifth distance exists between the second sub-light emitting layer in the third sub-pixel region and the reflective surface, the fifth distance is greater than the fourth distance, the fifth distance is greater than the first distance, and the fourth distance is less than the first distance.

10. The display panel according to claim 9, characterized in that: The value range of the first distance is: 1500 angstroms-2000 angstroms; The value range of the fourth distance is: 1500 angstroms-2000 angstroms; The value range of the fifth distance is: 2250 angstroms-2750 angstroms.

11. The display panel according to claim 8, characterized in that: Along the direction perpendicular to the substrate, the distance between the reflective surface and the second electrode layer is the microcavity length; The ratio of the microcavity length of the first sub-pixel region to half the emission wavelength of the first light-emitting layer is N1, the ratio of the microcavity length of the second sub-pixel region to half the emission wavelength of the first sub-light-emitting layer is N2, and the ratio of the microcavity length of the third sub-pixel region to half the emission wavelength of the second sub-light-emitting layer is N3, wherein N1, N2 and N3 are positive integers, N1 is greater than N2 and N1 is greater than N3.

12. The display panel according to claim 8, characterized in that: In a direction perpendicular to the base substrate, a sixth distance exists between a side of the first light-emitting layer close to the base substrate and a side of the first electrode far from the base substrate, a seventh distance exists between a side of the first light-emitting layer far from the base substrate and a side of the first sub-light-emitting layer close to the base substrate, and an eighth distance exists between a side of the second sub-light-emitting layer far from the base substrate and a side of the second electrode layer close to the base substrate; The sixth distance is greater than the eighth distance, and the eighth distance is greater than the seventh distance.

13. The display panel according to any one of claims 1 to 12, characterized in that: In a direction perpendicular to the base substrate, the distance between the first light emitting layer and the second electrode layer in each of the sub-pixel regions is substantially the same.

14. The display panel according to claims 1-12, characterized in that: The first light emitting layer is configured to emit blue light, and the second light emitting layer is configured to emit green light and red light.

15. A display device, characterized in that: include: A display panel as described in any one of claims 1 to 14.

Images