Display panel and display device
By providing an organic light emitting functional layer with a thickness greater than the metal protrusion in the OLED display panel, the contact between the second electrode layer and the metal protrusion is blocked, the problem of dark spots is solved, and the display quality and product yield are improved.
Patent Information
- Application Number
- CN202510300016.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-13
- Publication Date
- 2025-05-02
- Estimated Expiration
- 2045-03-13
AI Technical Summary
The problem of poor dark spots in the OLED display panel affects the product yield, which is mainly caused by the electrical connection caused by the contact between the metal protrusion and the second electrode layer.
The organic light emitting functional layer is provided in the display panel with a thickness greater than the thickness of the metal protrusion to prevent contact between the second electrode layer and the metal protrusion.
The dark spot defects caused by the contact between the metal protrusions and the second electrode layer are effectively avoided, and the display quality and product yield are improved.
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Figure CN119923074A_ABST
Abstract
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] 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] In the OLED production process, dark spot defects are one of the reasons that affect the product yield. Therefore, it is necessary to improve the dark spot defect problem of OLED to improve the product yield. Summary of the invention
[0004] Embodiments of the present disclosure provide a display panel and a display device, which can improve dark spot defects and enhance display quality and product yield.
[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] substrate substrate;
[0008] A first electrode layer is arranged on one side of the substrate, the first electrode layer comprises a plurality of first electrodes arranged at intervals, and a surface of at least one of the first electrodes away from the substrate has a metal protrusion;
[0009] An organic light-emitting functional layer is provided on a side of the first electrode layer away from the base substrate, and the organic light-emitting functional layer covers the metal protrusion;
[0010] A second electrode layer is arranged on a side of the organic light-emitting functional layer away from the first electrode layer;
[0011] In a direction perpendicular to the base substrate, the thickness of the organic light-emitting functional layer is greater than the thickness of the metal protrusion, so as to block the second electrode layer and the metal protrusion.
[0012] Optionally, the first electrode has a reflective surface, and a microcavity is formed between a side of the second electrode layer close to the substrate and the reflective surface;
[0013] The organic light-emitting functional layer includes at least one light-emitting layer. In a direction perpendicular to the substrate, there is a preset corresponding relationship between the cavity length of the microcavity and the number of microcavity periods. The number of microcavity periods is the number of times the light emitted by the light-emitting layer resonates in the microcavity. The cavity length of the microcavity is greater than or equal to the thickness of the organic light-emitting functional layer, and the number of microcavity periods corresponding to the cavity length of the microcavity is greater than or equal to 2.
[0014] Optionally, the organic light-emitting functional layer includes one light-emitting layer, and the cavity length of the microcavity corresponds to a number of microcavity periods of 3.
[0015] Optionally, the organic light-emitting functional layer includes a plurality of the light-emitting layers, and the cavity length of the microcavity corresponds to a number of microcavity periods of 2 or 3.
[0016] Optionally, it also includes:
[0017] A plurality of sub-pixels, each of which includes the first electrode layer, the organic light-emitting functional layer, and the second electrode layer which are stacked;
[0018] A pixel definition layer, disposed on one side of the base substrate, comprising a plurality of pixel openings, wherein the pixel openings are configured to define a light emitting area of the sub-pixel, and the pixel openings expose at least a portion of the first electrode;
[0019] The surface of the first electrode located in the pixel opening has the metal protrusion.
[0020] Optionally, the organic light-emitting functional layer includes a plurality of light-emitting units arranged at intervals, and at least one of the light-emitting units includes a protruding portion and a flat portion connected to each other, and the protruding portion covers the metal protruding portion.
[0021] Optionally, the organic light-emitting functional layer includes a plurality of light-emitting units arranged at intervals, and the second electrode layer includes a plurality of second electrodes;
[0022] The display panel further includes a plurality of sub-pixels, each of which includes the first electrode, the light-emitting unit, and the second electrode stacked in sequence;
[0023] The plurality of sub-pixels include a first sub-pixel, a second sub-pixel, and a third sub-pixel, wherein the light emitting units in the first sub-pixel, the second sub-pixel, and the third sub-pixel are configured to emit light of different colors;
[0024] The cavity length of the microcavity of the first sub-pixel ranges from 2750 angstroms to 3350 angstroms; the cavity length of the microcavity of the second sub-pixel ranges from 3500 angstroms to 4300 angstroms; the cavity length of the microcavity of the third sub-pixel ranges from 4100 angstroms to 5100 angstroms.
[0025] Optionally, the organic light-emitting functional layer further comprises: a hole transport layer, a buffer layer and an electron transport layer stacked in sequence, and the light-emitting layer is arranged between the buffer layer and the electron transport layer;
[0026] In a direction perpendicular to the substrate, the thickness of the hole transport layer ranges from 2000 angstroms to 2500 angstroms, and / or the thickness of the electron transport layer ranges from 200 angstroms to 500 angstroms;
[0027] The substrate includes a plurality of sub-pixels, including a first sub-pixel, a second sub-pixel and a third sub-pixel. In a direction perpendicular to the substrate, a buffer layer of the first sub-pixel has a thickness range of 50 angstroms to 150 angstroms, a buffer layer of the second sub-pixel has a thickness range of 500 angstroms to 1000 angstroms, and a buffer layer of the third sub-pixel has a thickness range of 1000 angstroms to 1500 angstroms; and / or a light-emitting layer of the first sub-pixel has a thickness range of 200 angstroms to 500 angstroms, a light-emitting layer of the second sub-pixel has a thickness range of 300 angstroms to 700 angstroms, and a light-emitting layer of the third sub-pixel has a thickness range of 500 angstroms to 1000 angstroms.
[0028] Optionally, the at least one organic light-emitting layer includes a first light-emitting layer and a second light-emitting layer, and the organic light-emitting functional layer further includes: a hole transport layer, a first buffer layer, a charge generation layer, a second buffer layer and an electron transport layer stacked in sequence, the first light-emitting layer is arranged between the first buffer layer and the charge generation layer, and the second light-emitting layer is arranged between the second buffer layer and the charge generation layer;
[0029] In a direction perpendicular to the substrate, the thickness of the hole transport layer ranges from 1000 angstroms to 1500 angstroms, the thickness of the charge generation layer ranges from 100 angstroms to 300 angstroms, and / or the thickness of the electron transport layer ranges from 200 angstroms to 500 angstroms;
[0030] The substrate includes a plurality of sub-pixels, including a first sub-pixel, a second sub-pixel and a third sub-pixel; in a direction perpendicular to the substrate, the thickness of the first buffer layer and the second buffer layer of the first sub-pixel ranges from 100 angstroms to 300 angstroms, the thickness of the first buffer layer and the second buffer layer of the second sub-pixel ranges from 300 angstroms to 500 angstroms, and the thickness of the first buffer layer and the second buffer layer of the third sub-pixel ranges from 500 angstroms to 1000 angstroms; and / or, the thickness of the first light-emitting layer and the second light-emitting layer of the first sub-pixel ranges from 200 angstroms to 500 angstroms, the thickness of the first light-emitting layer and the second light-emitting layer of the second sub-pixel ranges from 300 angstroms to 700 angstroms, and the thickness of the first light-emitting layer and the second light-emitting layer of the third sub-pixel ranges from 500 angstroms to 1000 angstroms.
[0031] 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.
[0032] The display panel provided by the embodiment of the present disclosure includes: a base substrate, a first electrode layer, an organic light-emitting functional layer and a second electrode layer. 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 surface of at least one first electrode away from the base substrate has a metal protrusion. The organic light-emitting functional layer is arranged on the side of the first electrode layer away from the base substrate, and the organic light-emitting functional layer covers the metal protrusion. The second electrode layer is arranged on the side of the organic light-emitting functional layer away from the first electrode layer. In the direction perpendicular to the base substrate, the thickness of the organic light-emitting functional layer is greater than the thickness of the metal protrusion to block the second electrode layer from the metal protrusion, thereby avoiding dark spots caused by the contact between the metal protrusion and the second electrode layer, so that the first electrode layer and the second electrode layer are electrically connected, thereby improving the display quality and product yield.
[0033] 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
[0034] 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:
[0035] Figure 1 A schematic diagram of a microcavity structure in the related art is shown;
[0036] Figure 2A schematic diagram showing the structure of a display panel in the related art is shown;
[0037] Figure 3 A schematic diagram showing a dark spot defect of a display panel in the related art is shown;
[0038] Figure 4 A schematic diagram of a first partial cross-sectional structure of a display panel according to an embodiment of the present application is shown;
[0039] Figure 5 A second partial cross-sectional structural schematic diagram of a display panel according to an embodiment of the present application is shown;
[0040] Figure 6 A third partial cross-sectional structural schematic diagram of the display panel according to the embodiment of the present application is shown;
[0041] Figure 7 A structural block diagram of a display device according to an embodiment of the present disclosure is shown.
[0042] Among them, 100-display panel; 10-base substrate; 11-anode; 12-organic light-emitting layer; 13-cathode; 14-metal protrusion; 200-display panel; 20-base substrate; 201-sub-pixel; 202-first sub-pixel; 203-second sub-pixel; 204-third sub-pixel; 21-first electrode layer; 211-reflective surface; 22-organic light-emitting functional layer; 22A-hole transport layer; 22B-buffer layer; 22C-light-emitting layer; 22D-electron transport layer; 22E-first buffer layer; 22F-second buffer layer; 22G-charge generation layer; 22H-first light-emitting layer; 22I-second light-emitting layer; 221-protrusion; 222-flat portion; 23-second electrode layer; 24-metal protrusion; 25-pixel definition layer; 300-display device. DETAILED DESCRIPTION
[0043] 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.
[0044] 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.
[0045] 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.
[0046] 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.
[0047] 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).
[0048] 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.
[0049] 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.
[0050] 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.
[0051] 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.
[0052] 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.
[0053] 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.
[0054] 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".
[0055] 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.
[0056] 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.
[0057] Figure 1 A schematic diagram of a microcavity structure in related art is shown.
[0058] It should be noted that Figure 1 The anode layer 01 and the cathode layer 02 are shown, and light emitted after multiple reflections between the anode layer 01 and the cathode layer 02, the light is emitted by the organic light-emitting layer between the anode layer 01 and the cathode layer 02 (not shown). Figure 1 When the vertical distance between the anode layer 01 and the cathode layer 02 meets certain conditions (for example, it is an integer multiple of half the wavelength of light), a microcavity is formed between the anode layer 01 and the cathode layer 02. As a result, the light emitted by the organic light-emitting layer is reflected and resonated multiple times in the microcavity before being emitted from the cathode layer 02, thereby improving the light extraction efficiency.
[0059] Since most organic light-emitting devices have a wide luminous spectrum and low color purity, in order to solve the problem of luminous color purity, such as Figure 1 As shown in Figure 1, introducing an optical microcavity into a light-emitting device is a good method. In some OLED products, the metal used as the anode is a fully reflective layer, and the metal used as the cathode is a semi-reflective layer. The luminescent material is excited to emit light between the two metal layers, and the light spontaneously radiates back and forth in the optical microcavity until it reaches the output interface. The introduction of the microcavity narrows the spectrum of the OLED luminescent material, increases the color purity, and improves the light output efficiency.
[0060] In the OLED manufacturing process, the anode is usually made of a transparent conductive material such as indium tin oxide (ITO). In order to introduce a microcavity, a thin metal layer (such as an aluminum metal layer) can be set on the surface of the anode as a reflective layer to form a microcavity between the anode and the cathode. However, since silver ions (Ag + ) solution, when silver ions come into contact with aluminum on the anode surface, under appropriate conditions (such as the pH value of the solution, temperature, etc.), silver ions and aluminum may undergo the following replacement reaction:
[0061] Ag + +Al→Al 3+ +Ag;
[0062] In the above replacement reaction, aluminum acts as a reducing agent to provide electrons to silver ions, reducing them to silver atoms (Ag). Due to the high activity of aluminum, it is easier to lose electrons and become aluminum ions into the solution, while silver ions are reduced and deposited on the anode surface, thus forming silver particles (Ag particles).
[0063] In this reaction, aluminum acts as a reducing agent to provide electrons to silver ions, reducing them to silver atoms (Ag). Due to the high activity of aluminum, it is easier for it to lose electrons and become aluminum ions and enter the solution, while the silver ions are reduced and deposited on the aluminum surface or nearby areas to form silver particles (Ag particles). In other words, in the etching solution, if the concentration of silver ions is high and aluminum metal is exposed to the anode surface, the above-mentioned replacement reaction may occur, resulting in the generation of more silver particles.
[0064] Figure 2 A schematic diagram showing the structure of a display panel in the related art is shown; Figure 3 A schematic diagram showing a dark spot defect of a display panel in the related art is shown.
[0065] like Figure 2 As shown, the display panel 100 in the related art includes a base substrate 10, an anode 11, an organic light-emitting layer 12 and a cathode 13 sequentially stacked on the base substrate 10. When silver particles are deposited on the surface of the anode 11, a metal protrusion 14 is formed on the surface of the anode 11. When the organic light-emitting material of the OLED is subsequently evaporated, since the organic light-emitting material is usually thin, the presence of the metal protrusion 14 may cause cracks in the organic light-emitting material at the protrusion position, so that the cathode 13 material prepared subsequently contacts the metal protrusion 14, and then the cathode 13 contacts the anode 11, that is, the cathode 13 overlaps the anode 11. The overlap of the cathode 13 and the anode 11 may cause the current to bypass the organic light-emitting layer 12 and flow directly from the cathode 13 to the anode 11, forming a current leakage path, that is, the current that should originally pass through the organic light-emitting layer 12 is shunted, thereby reducing or even preventing the light emission of the organic light-emitting layer 12, forming a dark spot defect (such as Figure 3 ), thereby affecting the display quality and product yield of the display product.
[0066] In addition, in the OLED manufacturing process, after the BP (Backplane) is prepared and before the EV (Electrode Vaporization) process, the longer the BP is placed, if the backplane is exposed to the air or in an environment that does not meet the cleanliness standards, it may absorb dust, moisture or other pollutants. These pollutants will affect the quality of subsequent organic layers and electrode layers. For example, it will cause bulges in certain locations of the anode 11 layer, which may also cause the anode 11 layer and the cathode 13 layer to overlap, causing pixel failure and forming dark spots.
[0067] In view of this, an embodiment of the present application provides a display panel, which can to a certain extent avoid dark spots caused by the metal protrusion contacting the second electrode layer, thereby electrically connecting the first electrode layer and the second electrode layer, thereby improving display quality and product yield.
[0068] The display panel according to the embodiment of the present application will be described below with reference to specific drawings.
[0069] Figure 4 A schematic diagram of a first partial cross-sectional structure of a display panel according to an embodiment of the present application is shown. Figure 5 A second partial cross-sectional structural schematic diagram of the display panel according to an embodiment of the present application is shown.
[0070] It should be noted that in order to make the structure of the partial cross section of the display panel more clearly displayed, Figure 4 The structure of the organic light-emitting functional layer is simplified and Figure 5 The various film layers included in the organic light-emitting functional layer are shown in detail.
[0071] In a first aspect, the present disclosure provides a display panel 200, comprising: a base substrate 20, a first electrode layer 21, an organic light-emitting functional layer 22, and a second electrode layer 23. The first electrode layer 21 is disposed on one side of the base substrate 20, the first electrode layer 21 comprises a plurality of first electrodes disposed at intervals, and a surface of at least one of the first electrodes away from the base substrate 20 has a metal protrusion 24. The organic light-emitting functional layer 22 is disposed on a side of the first electrode layer 21 away from the base substrate 20, and the organic light-emitting functional layer 22 covers the metal protrusion 24. The second electrode layer 23 is disposed on a side of the organic light-emitting functional layer 22 away from the first electrode layer 21. In a direction perpendicular to the base substrate 20, the thickness H1 of the organic light-emitting functional layer 22 is greater than the thickness H2 of the metal protrusion 24, so as to block the second electrode layer 23 from the metal protrusion 24.
[0072] In some embodiments, the first electrode layer 21 may be an anode layer, and the second electrode layer 23 may be a cathode layer; in some embodiments, the first electrode layer 21 may also be a cathode layer, and the second electrode layer 23 may be an anode layer. For ease of description, the embodiments of the present disclosure are described by taking the first electrode layer 21 as an anode layer and the second electrode layer 23 as a cathode layer as an example.
[0073] In some embodiments, the second anode layer may include a plurality of independent second electrodes, each of which is electrically connected to a corresponding first electrode, or the second anode layer may include a whole layer of second electrodes, and the second electrodes are electrically connected to each of the first electrodes.
[0074] In the embodiment of the present application, the first electrode layer 21 is an anode layer, and the anode layer includes a plurality of anodes arranged at intervals. In the anode etching process, the etching solution may contain silver ions, such as metal (such as aluminum metal) on the surface of the anode undergoes a replacement reaction, thereby depositing a metal protrusion 24, such as silver particles, on the surface of at least one anode in the anode layer. It is understandable that the more metal protrusions 24 are formed on the surface of the anode, the more dark spots and bad areas may be caused, thereby worsening the display quality.
[0075] It can be understood that since the organic light-emitting functional layer 22 is evaporated on the anode, in the direction perpendicular to the base substrate 20, the thickness H1 of the organic light-emitting functional layer 22 is greater than the thickness H2 of the metal protrusion 24. Therefore, the organic light-emitting functional layer 22 can cover the surface of the metal protrusion 24 (that is, the surface of the metal protrusion 24 away from the base substrate 20), thereby preventing the metal protrusion 24 from contacting the cathode, and further preventing the cathode and the anode from overlapping, thereby solving the problem of dark spots and improving the display quality and product yield.
[0076] Continue to see Figure 4 or Figure 5 , in some embodiments, further comprising: a plurality of sub-pixels 201 and a pixel definition layer 25. The sub-pixel 201 comprises the first electrode layer 21, the organic light-emitting functional layer 22 and the second electrode layer 23 which are stacked. The pixel definition layer 25 is disposed on one side of the base substrate 20, and comprises a plurality of pixel openings, wherein the pixel openings are configured to define the light-emitting area of the sub-pixel 201, the pixel openings expose at least a portion of the first electrode, and the surface of the first electrode located in the pixel openings has the metal protrusion 24.
[0077] It is understandable that the pixel opening defines the light-emitting area of the sub-pixel 201, and the organic light-emitting functional layer 22 emits light in the light-emitting area. Therefore, if the surface of the first electrode located in the pixel opening has a metal protrusion 24, it is possible that cracks will be generated in the organic light-emitting functional layer 22 at the location of the metal protrusion 24, thereby causing the metal protrusion 24 to contact the second electrode layer 23, and then causing the first electrode layer 21 and the second electrode layer 23 to overlap and cause dark spots. Therefore, the embodiment of the present application sets the thickness of the organic light-emitting functional layer 22 located in the pixel opening to be greater than the metal protrusion 24, which can avoid the metal protrusion 24 from contacting the second electrode layer 23, and then avoid the first electrode layer 21 and the second electrode layer 23 from overlapping and causing dark spots.
[0078] In some embodiments, the organic light-emitting functional layer 22 includes a plurality of light-emitting units arranged at intervals, and at least one of the light-emitting units includes a protruding portion 221 and a flat portion 222 connected to each other, and the protruding portion 221 covers the metal protruding portion 24 .
[0079] It can be understood that the metal protrusion 24 is formed on the surface of the first electrode due to certain process defects. For example, the aluminum metal of the first electrode mentioned above undergoes a replacement reaction with the silver ions in the etching solution. Therefore, usually not all surfaces of the first electrode will have metal protrusions 24 (such as silver particles). Correspondingly, not all light-emitting units will have corresponding protrusions when the light-emitting units are evaporated on the surface of the first electrode due to the presence of the metal protrusion 24. That is, the organic light-emitting functional layer 22 includes a plurality of light-emitting units arranged at intervals, and at least one light-emitting unit includes a protrusion 221, and the protrusion 221 covers the metal protrusion 24.
[0080] At present, a display screen is generally composed of RGB (Red Green Blue) three-color sub-pixels 201. Each color sub-pixel 201 corresponds to a light-emitting device, and the three colors of pixels correspond to three light-emitting devices with different structures. Different light-emitting devices emit light with different wavelengths. For example, the wavelength of red light is greater than that of green light, and the wavelength of green light is greater than that of blue light.
[0081] It is understandable that when the anode and the cathode have reflective properties, the multiple beams of light emitted by the organic light-emitting layer 22C 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 22C, 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 two beams of light have the same period, the two beams of light will meet at the crest and at the trough, so that after the two beams of light are superimposed, the intensity of the beams 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 OLED, if the multiple beams of light emitted by the organic light-emitting layer 22C 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, and 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.
[0082] It can be seen that the introduction of microcavities narrows the spectrum of OLED luminescent materials, increases color purity and improves light extraction efficiency. Microcavity gain is periodic, which allows light to be enhanced or suppressed in the microcavity, depending on the relative size between the half-wavelength of the light and the length of the microcavity. For example, it can be characterized by the following formula:
[0083]
[0084] Wherein, L represents the length of the microcavity, m represents the resonance order or the number of microcavity periods, λ represents the wavelength of light, and n represents the effective refractive index of the medium in the microcavity.
[0085] It can be seen from the above formula (1) that when the microcavity length is an integer multiple of the half wavelength of light, the light emitted by the organic light-emitting layer 22C can form a standing wave in the microcavity, thereby obtaining gain. For a given microcavity length and effective refractive index, each resonance order corresponds to a specific resonance wavelength. Conversely, for a given emission wavelength and effective refractive index, each resonance order corresponds to a specific microcavity length, and there is a positive correlation between the resonance order and the microcavity length, that is, the larger the resonance order, the larger the microcavity length, and the smaller the resonance order, the smaller the microcavity length. In the related art, the resonance order usually selected for the RGB process is 1, that is, the number of microcavity periods is 1, but the inventors found in the process of preparing the OLED display panel 200 that when the number of microcavity periods is 1, the microcavity length is small, so the corresponding thickness of the organic light-emitting functional layer 22 is small, so that the organic light-emitting functional layer 22 is too thin and it is easy to produce cracks at the position of the metal protrusion 24, thereby causing dark spot defects.
[0086] In view of this, the embodiments of the present application propose the following embodiments based on the above-mentioned corresponding relationship between the microcavity length and the wavelength.
[0087] In some embodiments, the first electrode has a reflective surface 211, and a microcavity is formed between the side of the second electrode layer 23 close to the base substrate 20 and the reflective surface 211. The organic light-emitting functional layer 22 includes at least one light-emitting layer 22C, and in a direction perpendicular to the base substrate 20, there is a preset corresponding relationship between the cavity length H3 of the microcavity and the microcavity period number, the microcavity period number is the number of times the light emitted by the light-emitting layer 22C resonates in the microcavity, that is, the resonance order, the cavity length H3 of the microcavity is greater than or equal to the thickness H1 of the organic light-emitting functional layer 22, and the microcavity period number corresponding to the cavity length H3 of the microcavity is greater than or equal to 2.
[0088] Exemplarily, the first electrode has a reflective surface 211, and the reflective surface 211 may be a surface of the first electrode on a side away from the base substrate 20, or a surface of the first electrode on a side close to the base substrate 20. Figure 4The surface of the first electrode away from the substrate 20 is shown as the reflective surface 211. The second electrode layer 23 has a partial transmission and partial reflection characteristic (for example, a semi-transmission and semi-reflection characteristic, a 60% transmission and 40% reflection characteristic, a 55% transmission and 45% reflection characteristic, etc.), thereby forming a microcavity between the reflective surface 211 of the first electrode and the side of the second electrode layer 23 close to the substrate 20 (between the anode and the cathode). In the direction perpendicular to the substrate 20, the cavity length of the microcavity is the distance between the reflective surface 211 of the first electrode and the side of the second electrode layer 23 close to the substrate 20. As a result, the light beam directly emitted by the organic light-emitting functional layer 22 interferes with the light beam reflected at the interface of the first electrode (or the second electrode layer 23), and the microcavity between the first electrode layer 21 and the second electrode layer 23 can narrow the electroluminescent spectrum of the organic light-emitting functional layer 22, thereby improving the color purity, so that each sub-pixel 201 emits light of different colors.
[0089] It can be understood that, since a microcavity is formed between the reflective surface 211 of the first electrode and the side of the second electrode layer 23 close to the base substrate 20 (between the anode and the cathode), the cavity length H3 of the microcavity is related to the thickness H1 of the organic light-emitting functional layer 22 between the first electrode layer 21 and the second electrode layer 23. When the reflective surface 211 of the first electrode is the surface of the first electrode away from the base substrate 20, the cavity length H3 of the microcavity is equal to the thickness H1 of the organic light-emitting functional layer 22, and when the reflective surface 211 of the first electrode is the other surface of the first electrode (for example, the surface close to the base substrate 20), the cavity length H3 of the microcavity is greater than the thickness H1 of the organic light-emitting functional layer 22. When the reflective surface 211 of the first electrode is the surface of the first electrode close to the base substrate 20, the first electrode may include a reflective layer, an adjustment layer and a conductive layer (not shown) stacked in sequence, wherein the adjustment layer may be used to adjust the thickness of the first electrode, thereby adjusting the cavity length H3 of the microcavity.
[0090] Then, in combination with formula (1), the number of microcavity periods corresponding to the cavity length H3 of the microcavity is greater than or equal to 2, that is, the number of resonance orders corresponding to the cavity length H3 of the microcavity is greater than or equal to 2, for example, it can be 2, 3, 4, 5, etc. That is to say, in the embodiment of the present application, the thickness H1 of the organic light-emitting functional layer 22 is increased, and the organic light-emitting functional layer 22 with increased thickness H1 increases the cavity length H3 of the microcavity, and the number of microcavity periods corresponding to the increased cavity length H3 of the microcavity is greater than or equal to 2. Thus, the organic light-emitting functional layer 22 can cover the surface of the metal protrusion 24 (that is, the surface of the metal protrusion 24 away from the substrate 20), thereby preventing the metal protrusion 24 from contacting the cathode, and further preventing the cathode and the anode from overlapping, thereby solving the problem of poor dark spots and improving display quality and product yield.
[0091] It can be understood that according to formula (1), when the cavity length H3 of the microcavity is an integer multiple of the half wavelength of the light, the light emitted by the organic light-emitting layer 22C can form a standing wave in the microcavity, thereby obtaining gain. Since the wavelengths of the light emitted by the sub-pixels 201 of different colors are different, the cavity lengths of the microcavities corresponding to the different sub-pixels 201 are also different. Among them, for the red sub-pixel 201, the blue sub-pixel 201 and the green sub-pixel 201, the wavelength of the blue sub-pixel 201 is the smallest, so generally speaking, the cavity length of the microcavity of the blue sub-pixel 201 is set to the smallest. However, since the number of microcavity cycles in the related art is small, that is, the cavity length of the corresponding microcavity is small, the incidence rate of dark spot defects of the blue sub-pixel 201 is high. The embodiment of the present application reduces the incidence rate of dark spot defects of the blue sub-pixel 201 by increasing the cavity length of the microcavity of each sub-pixel 201, and of course also reduces the incidence rate of dark spot defects of the red sub-pixel 201 and the green sub-pixel 201.
[0092] It is understood that OLED devices may include Single (single layer) devices and Tandem (tandem) devices. A single layer device refers to a device containing a light emitting unit, which may include multiple organic layers sandwiched between an anode and a cathode, and these organic layers generally include a hole transport layer 22A (HTL), a light emitting layer 22C (EML) and an electron transport layer 22D (ETL). A tandem device is formed by stacking multiple light emitting units, each of which is separated by a connecting layer (charge generation layer 22G), and each light emitting unit can emit light independently, and each light emitting unit contributes to the total output brightness.
[0093] In some embodiments, the organic light-emitting functional layer 22 includes one light-emitting layer 22C, that is, the OLED device is a single-layer device, and the cavity length of the microcavity corresponds to the number of microcavity periods of 3.
[0094] In some embodiments, the organic light-emitting functional layer 22 includes a plurality of light-emitting layers 22C, that is, the OLED device is a series device, and the cavity length of the microcavity corresponds to a microcavity period number of 2 or 3.
[0095] In some embodiments, the organic light-emitting functional layer 22 includes a plurality of light-emitting units arranged at intervals, and the second electrode layer 23 includes a plurality of second electrodes. The display panel 200 also includes a plurality of sub-pixels 201, and the sub-pixels 201 include the first electrode, the light-emitting unit, and the second electrode stacked in sequence.
[0096] The plurality of sub-pixels 201 include a first sub-pixel 202, a second sub-pixel 203, and a third sub-pixel 204, wherein the light-emitting units in the first sub-pixel 202, the second sub-pixel 203, and the third sub-pixel 204 are configured to emit light of different colors. The cavity length H3 of the microcavity of the first sub-pixel 202 has a value range of 2750 angstroms to 3350 angstroms, such as 2750 angstroms, 2850 angstroms, 3000 angstroms, 3050 angstroms, 3100 angstroms, 3150 angstroms, 3200 angstroms, 3250 angstroms, 3350 angstroms, etc.; the cavity length H3 of the microcavity of the second sub-pixel 203 has a value range of 3500 angstroms to 4300 angstroms, such as 3500 angstroms, 3600 angstroms, 3700 angstroms, 3800 angstroms, 3900 angstroms, 4000 angstroms, 4100 angstroms, 4200 angstroms, 4300 angstroms, 4400 angstroms, 4500 angstroms, 4600 angstroms, 4700 angstroms, 4800 angstroms, 4900 angstroms, 5000 angstroms, 5100 angstroms, 5200 angstroms, 5300 angstroms, 5400 angstroms, 5500 angstroms, 5600 angstro 3700 angstroms, 3800 angstroms, 3900 angstroms, 4000 angstroms, 4100 angstroms, 4200 angstroms or 4300 angstroms; the cavity length H3 of the microcavity of the third sub-pixel 204 ranges from 4100 angstroms to 5100 angstroms, for example, 4100 angstroms, 4200 angstroms, 4300 angstroms, 4400 angstroms, 4500 angstroms, 4600 angstroms, 4700 angstroms, 4800 angstroms, 4900 angstroms, 5000 angstroms, 5100 angstroms, etc.
[0097] In some embodiments, the first sub-pixel 202 is a blue sub-pixel 201, the second sub-pixel 203 is a green sub-pixel 201, the third sub-pixel 204 is a red sub-pixel 201, the cavity length H3 of the microcavity of the blue sub-pixel 201 is 3050 angstroms, the cavity length H3 of the microcavity of the green sub-pixel 201 is 3900 angstroms, and the cavity length H3 of the microcavity of the red sub-pixel 201 is 4600 angstroms.
[0098] It can be understood that according to the above formula (1), when the cavity length H3 of the microcavity is an integer multiple of the half wavelength of the light, the light emitted by the light-emitting unit can be gained in the microcavity. In the embodiment of the present application, the cavity length H3 of the microcavity corresponding to the first sub-pixel 202, the second sub-pixel 203 and the third sub-pixel 204 is respectively taken as the above value, so that the number of microcavity periods corresponding to the cavity length H3 of the microcavity of each sub-pixel 201 is greater than or equal to 2, for example, 3, that is, by increasing the cavity length H3 of the microcavity, the contact possibility between the metal protrusion 24 and the second electrode layer 23 is reduced, thereby reducing the dark spot defect rate.
[0099] In some embodiments, when the OLED is a single-layer device, the organic light-emitting functional layer 22 further includes: a hole transport layer 22A (HTL), a buffer layer 22B and an electron transport layer 22D (ETL) stacked in sequence, and the light-emitting layer 22C is provided between the buffer layer 22B and the electron transport layer 22D. In the direction perpendicular to the base substrate 20, the thickness of the hole transport layer 22A ranges from 2000 angstroms to 2500 angstroms, for example, 2000 angstroms, 2100 angstroms, 2200 angstroms, 2300 angstroms, 2400 angstroms or 2500 angstroms, and / or the thickness of the electron transport layer 22D ranges from 200 angstroms to 500 angstroms, for example, 200 angstroms, 300 angstroms, 400 angstroms or 500 angstroms.
[0100] The base substrate 20 includes a plurality of sub-pixels 201. The plurality of sub-pixels 201 include a first sub-pixel 202, a second sub-pixel 203, and a third sub-pixel 204. In a direction perpendicular to the base substrate 20, the thickness of the buffer layer 22B of the first sub-pixel 202 ranges from 50 angstroms to 150 angstroms, such as 50 angstroms, 60 angstroms, 70 angstroms, 80 angstroms, 90 angstroms, 100 angstroms, 120 angstroms, 140 angstroms, or 150 angstroms. The thickness of the buffer layer 22B of the second sub-pixel 203 ranges from 500 angstroms to 1000 angstroms, such as 500 angstroms, 600 angstroms, 700 angstroms, 800 angstroms, 900 angstroms, or 1000 angstroms. The thickness of the buffer layer 22B of the third sub-pixel 204 ranges from 1000 angstroms to 1500 angstroms, for example, 1000 angstroms, 1100 angstroms, 1200 angstroms, 1250 angstroms, 1300 angstroms, 1400 angstroms or 1500 angstroms. And / or, the thickness range of the light-emitting layer 22C of the first sub-pixel 202 is: 200 angstroms-500 angstroms, for example, 200 angstroms, 300 angstroms, 400 angstroms or 500 angstroms, the thickness range of the light-emitting layer 22C of the second sub-pixel 203 is: 300 angstroms-700 angstroms, for example, 300 angstroms, 400 angstroms, 500 angstroms, 600 angstroms or 700 angstroms, the thickness range of the light-emitting layer 22C of the third sub-pixel 204 is: 500 angstroms-1000 angstroms, for example, 500 angstroms, 600 angstroms, 700 angstroms, 800 angstroms, 900 angstroms or 1000 angstroms.
[0101] For example, when the OLED is a single-layer device, the hole transport layer 22A can be made of triphenylamine polymer, butadiene and other materials, and different materials have different refractive indices N and extinction coefficients K.
[0102] Exemplarily, when the OLED is a single-layer device, the buffer layer 22B may be a hole transport layer 22A for matching energy levels to reduce the potential barrier in the hole transport process and improve the transport efficiency. The buffer layer 22B may be made of triphenylamine polymer, butadiene and other materials, and the refractive index N and extinction coefficient K of different materials are different. The thickness of the buffer layer 22B corresponding to different sub-pixels 201 may be different, for example: the thickness of the buffer layer 22B of the blue sub-pixel 201 is 50 angstroms to 150 angstroms, the thickness of the buffer layer 22B of the green sub-pixel 201 is 500 angstroms to 1000 angstroms, and the thickness of the buffer layer 22B of the red sub-pixel 201 is 1000 angstroms to 1500 angstroms.
[0103] Exemplarily, when the OLED is a single-layer device, the light-emitting layer 22C (EML) can be prepared using materials such as rhodamine dyes, coumarin dyes, and N-aromatic benzimidazoles, and different materials have different refractive indices N and extinction coefficients K. The thickness of the light-emitting layer 22C of different sub-pixels 201 can be different, for example: the thickness of the light-emitting layer 22C of the blue sub-pixel 201 is 200 angstroms to 500 angstroms, the thickness of the light-emitting layer 22C of the green sub-pixel 201 is 300 angstroms to 700 angstroms, and the thickness of the light-emitting layer 22C of the red sub-pixel 201 is 500 angstroms to 1000 angstroms.
[0104] Exemplarily, when the OLED is a single-layer device, the electron transport layer 22D (ETL) can be prepared using materials such as Alq (tris(8-hydroxyquinoline)aluminum), PBD (2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole), and different materials have different refractive indices N and extinction coefficients K.
[0105] Figure 6 A third partial cross-sectional structural schematic diagram of the display panel 200 according to the embodiment of the present application is shown.
[0106] In some embodiments, when the OLED is a tandem device, the at least one organic light-emitting layer 22C includes a first light-emitting layer 22H and a second light-emitting layer 22I, and the organic light-emitting functional layer 22 further includes: a hole transport layer 22A, a first buffer layer 22E, a charge generation layer 22G, a second buffer layer 22F and an electron transport layer 22D stacked in sequence, the first light-emitting layer 22H is provided between the first buffer layer 22E and the charge generation layer 22G, and the second light-emitting layer 22I is provided between the second buffer layer 22F and the charge generation layer 22G;
[0107] In the direction perpendicular to the base substrate 20, the thickness of the hole transport layer 22A ranges from 1000 angstroms to 1500 angstroms, for example, 1000 angstroms, 1100 angstroms, 1200 angstroms, 1300 angstroms, 1400 angstroms or 1500 angstroms, the thickness of the charge generation layer 22G (including the N-type charge generation layer 22G and the P-type charge generation layer 22G) ranges from 100 angstroms to 300 angstroms, for example, 100 angstroms, 200 angstroms or 300 angstroms, and / or the thickness of the electron transport layer 22D ranges from 200 angstroms to 500 angstroms, for example, 200 angstroms, 300 angstroms, 400 angstroms or 500 angstroms.
[0108] The base substrate 20 includes a plurality of sub-pixels 201, and the plurality of sub-pixels 201 include a first sub-pixel 202, a second sub-pixel 203, and a third sub-pixel 204. In a direction perpendicular to the base substrate 20, the thickness of the first buffer layer 22E and the second buffer layer 22F of the first sub-pixel 202 ranges from 100 angstroms to 300 angstroms, for example, 100 angstroms, 200 angstroms, or 300 angstroms. The thickness of the first buffer layer 22E and the second buffer layer 22F of the second sub-pixel 203 ranges from 300 angstroms to 500 angstroms, for example, 300 angstroms, 400 angstroms, or 500 angstroms. The thickness of the first buffer layer 22E and the second buffer layer 22F of the third sub-pixel 204 ranges from 500 angstroms to 1000 angstroms, for example, 500 angstroms. , 600 angstroms, 700 angstroms, 800 angstroms, 900 angstroms or 1000 angstroms; and / or, the thickness range of the first light-emitting layer 22H and the second light-emitting layer 22I of the first sub-pixel 202 is: 200 angstroms-500 angstroms, for example, 200 angstroms, 300 angstroms, 400 angstroms, 500 angstroms, the thickness range of the first light-emitting layer 22H and the second light-emitting layer 22I of the second sub-pixel 203 is: 300 angstroms-700 angstroms, for example, 300 angstroms, 400 angstroms, 500 angstroms, 600 angstroms or 700 angstroms, the thickness range of the first light-emitting layer 22H and the second light-emitting layer 22I of the third sub-pixel 204 is: 500 angstroms-1000 angstroms, for example, 500 angstroms, 600 angstroms, 700 angstroms, 800 angstroms, 900 angstroms or 1000 angstroms.
[0109] For example, when the OLED is a tandem device, the hole transport layer 22A can be made of triphenylamine polymer, butadiene and other materials, and the refractive index N and extinction coefficient K of different materials are different.
[0110] Exemplarily, when the OLED is a single-layer device, the buffer layer 22B may be a hole transport layer 22A for matching energy levels to reduce the potential barrier in the hole transport process and improve the transport efficiency. The buffer layer 22B may be prepared using triphenylamine polymer, butadiene and other materials, and the refractive index N and extinction coefficient K of different materials are different. Among them, the thickness of the buffer layer 22B corresponding to different sub-pixels 201 may be different, for example: the thickness of the first buffer layer 22E and the second buffer layer 22F of the blue sub-pixel 201 is 100 angstroms to 300 angstroms, the thickness of the first buffer layer 22E and the second buffer layer 22F of the green sub-pixel 201 is 300 angstroms to 500 angstroms, and the thickness of the first buffer layer 22E and the second buffer layer 22F of the red sub-pixel 201 is 1000 angstroms to 1500 angstroms.
[0111] Exemplarily, when the OLED is a tandem device, the light-emitting layer 22C (EML) can be prepared using rhodamine dyes, coumarin dyes, N-aromatic benzimidazoles and other materials, and different materials have different refractive indices N and extinction coefficients K. The thicknesses of the first light-emitting layer 22H and the second light-emitting layer 22I of different sub-pixels 201 can be different, for example: the thickness of the first light-emitting layer 22H and the second light-emitting layer 22I of the blue sub-pixel 201 is 200 angstroms to 500 angstroms, the thickness of the first light-emitting layer 22H and the second light-emitting layer 22I of the green sub-pixel 201 is 300 angstroms to 700 angstroms, and the thickness of the first light-emitting layer 22H and the second light-emitting layer 22I of the red sub-pixel 201 is 500 angstroms to 1000 angstroms.
[0112] Exemplarily, when the OLED is a tandem device, the electron transport layer 22D (ETL) can be prepared using materials such as Alq (tris(8-hydroxyquinoline)aluminum), PBD (2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole), and different materials have different refractive indices N and extinction coefficients K.
[0113] In some embodiments, the second electrode layer 23 is a cathode layer, and the thickness of the cathode layer in the direction perpendicular to the substrate 20 ranges from 100 angstroms to 200 angstroms, for example, 100 angstroms, 150 angstroms or 200 angstroms; and / or, the cathode layer can be prepared using metal materials such as Mg (magnesium), Ag (silver) or Al (aluminum).
[0114] In some embodiments, the display panel 200 also includes a light extraction layer (CPL) (not shown), which is arranged on the side of the second electrode layer 23 away from the base substrate 20. In the direction perpendicular to the base substrate 20, the thickness of the light extraction layer ranges from 500 angstroms to 900 angstroms, for example, 500 angstroms, 600 angstroms, 700 angstroms, 800 angstroms or 900 angstroms.
[0115] Figure 7A structural block diagram of a display device according to an embodiment of the present disclosure is shown.
[0116] 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.
[0117] Exemplarily, 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.
[0118] 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.
[0119] 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: substrate substrate; A first electrode layer is arranged on one side of the substrate, the first electrode layer comprises a plurality of first electrodes arranged at intervals, and a surface of at least one of the first electrodes away from the substrate has a metal protrusion; An organic light-emitting functional layer is provided on a side of the first electrode layer away from the base substrate, and the organic light-emitting functional layer covers the metal protrusion; A second electrode layer is arranged on a side of the organic light-emitting functional layer away from the first electrode layer; In a direction perpendicular to the base substrate, the thickness of the organic light-emitting functional layer is greater than the thickness of the metal protrusion, so as to block the second electrode layer and the metal protrusion.
2. The display panel according to claim 1, characterized in that: The first electrode has a reflective surface, and a microcavity is formed between a side of the second electrode layer close to the substrate and the reflective surface; The organic light-emitting functional layer includes at least one light-emitting layer. In a direction perpendicular to the substrate, there is a preset corresponding relationship between the cavity length of the microcavity and the number of microcavity periods. The number of microcavity periods is the number of times the light emitted by the light-emitting layer resonates in the microcavity. The cavity length of the microcavity is greater than or equal to the thickness of the organic light-emitting functional layer, and the number of microcavity periods corresponding to the cavity length of the microcavity is greater than or equal to 2.
3. The display panel according to claim 2, characterized in that: The organic light-emitting functional layer includes one light-emitting layer, and the cavity length of the microcavity corresponds to a number of microcavity periods of 3.
4. The display panel according to claim 2, characterized in that: The organic light-emitting functional layer includes a plurality of light-emitting layers, and the cavity length of the microcavity corresponds to a microcavity period number of 2 or 3.
5. The display panel according to claim 1, characterized in that: Also includes: A plurality of sub-pixels, each of which includes the first electrode layer, the organic light-emitting functional layer, and the second electrode layer which are stacked; A pixel definition layer, disposed on one side of the base substrate, comprising a plurality of pixel openings, wherein the pixel openings are configured to define a light emitting area of the sub-pixel, and the pixel openings expose at least a portion of the first electrode; The surface of the first electrode located in the pixel opening has the metal protrusion.
6. The display panel according to claim 1, characterized in that: The organic light-emitting functional layer includes a plurality of light-emitting units arranged at intervals, at least one of the light-emitting units includes a protruding portion and a flat portion connected to each other, and the protruding portion covers the metal protruding portion.
7. The display panel according to claim 1, characterized in that: The organic light-emitting functional layer includes a plurality of light-emitting units arranged at intervals, and the second electrode layer includes a plurality of second electrodes; The display panel further includes a plurality of sub-pixels, each of which includes the first electrode, the light-emitting unit, and the second electrode stacked in sequence; The plurality of sub-pixels include a first sub-pixel, a second sub-pixel, and a third sub-pixel, wherein the light emitting units in the first sub-pixel, the second sub-pixel, and the third sub-pixel are configured to emit light of different colors; The cavity length of the microcavity of the first sub-pixel ranges from 2750 angstroms to 3350 angstroms; the cavity length of the microcavity of the second sub-pixel ranges from 3500 angstroms to 4300 angstroms; the cavity length of the microcavity of the third sub-pixel ranges from 4100 angstroms to 5100 angstroms.
8. The display panel according to claim 3, characterized in that: The organic light-emitting functional layer further comprises: a hole transport layer, a buffer layer and an electron transport layer stacked in sequence, wherein the light-emitting layer is disposed between the buffer layer and the electron transport layer; In a direction perpendicular to the substrate, the thickness of the hole transport layer ranges from 2000 angstroms to 2500 angstroms, and / or the thickness of the electron transport layer ranges from 200 angstroms to 500 angstroms; The substrate includes a plurality of sub-pixels, including a first sub-pixel, a second sub-pixel and a third sub-pixel. In a direction perpendicular to the substrate, a buffer layer of the first sub-pixel has a thickness range of 50 angstroms to 150 angstroms, a buffer layer of the second sub-pixel has a thickness range of 500 angstroms to 1000 angstroms, and a buffer layer of the third sub-pixel has a thickness range of 1000 angstroms to 1500 angstroms; and / or a light-emitting layer of the first sub-pixel has a thickness range of 200 angstroms to 500 angstroms, a light-emitting layer of the second sub-pixel has a thickness range of 300 angstroms to 700 angstroms, and a light-emitting layer of the third sub-pixel has a thickness range of 500 angstroms to 1000 angstroms.
9. The display panel according to claim 4, characterized in that: The at least one organic light-emitting layer includes a first light-emitting layer and a second light-emitting layer, and the organic light-emitting functional layer further includes: a hole transport layer, a first buffer layer, a charge generation layer, a second buffer layer and an electron transport layer stacked in sequence, the first light-emitting layer is arranged between the first buffer layer and the charge generation layer, and the second light-emitting layer is arranged between the second buffer layer and the charge generation layer; In a direction perpendicular to the substrate, the thickness of the hole transport layer ranges from 1000 angstroms to 1500 angstroms, the thickness of the charge generation layer ranges from 100 angstroms to 300 angstroms, and / or the thickness of the electron transport layer ranges from 200 angstroms to 500 angstroms; The substrate includes a plurality of sub-pixels, including a first sub-pixel, a second sub-pixel and a third sub-pixel; in a direction perpendicular to the substrate, the thickness of the first buffer layer and the second buffer layer of the first sub-pixel ranges from 100 angstroms to 300 angstroms, the thickness of the first buffer layer and the second buffer layer of the second sub-pixel ranges from 300 angstroms to 500 angstroms, and the thickness of the first buffer layer and the second buffer layer of the third sub-pixel ranges from 500 angstroms to 1000 angstroms; and / or, the thickness of the first light-emitting layer and the second light-emitting layer of the first sub-pixel ranges from 200 angstroms to 500 angstroms, the thickness of the first light-emitting layer and the second light-emitting layer of the second sub-pixel ranges from 300 angstroms to 700 angstroms, and the thickness of the first light-emitting layer and the second light-emitting layer of the third sub-pixel ranges from 500 angstroms to 1000 angstroms.
10. A display device, characterized in that: include: A display panel as described in any one of claims 1 to 9.
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