Display panel

Abstract

The invention provides a display panel which comprises a driving back plate, a plurality of light-emitting elements which are located on one side of the driving back plate and arranged in an array, and the light-emitting elements emit blue light. The quantum dot material layer is located on the side, away from the driving backboard, of the light-emitting element; the color conversion layer is located on the side, away from the driving backboard, of the quantum dot material layer and can enable the multiple light-emitting elements to achieve color display; the orthographic projection of the color conversion layer and the quantum dot material layer on the driving backboard at least covers the orthographic projection of the light-emitting element on the driving backboard; the quantum dot material layer comprises a red quantum dot material and a green quantum dot material, and the quantum dot material layer can convert blue light emitted by the light-emitting element into white light. The display panel not only can realize full-color display, but also can reduce the preparation process difficulty of light-emitting elements with different colors and improve the yield of the light-emitting elements with different colors.

Description

Technical Field

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

[0002] With the continuous advancement of display technology, the resolution of current display products is getting higher and higher. OLED (Organic Light-Emitting Diode) display devices and Micro LED (Micro Light Emitting Diode Display) display devices can both achieve higher resolutions, but OLED display devices generally have a short lifespan, while micro LED display devices have the advantages of long lifespan and high brightness. Summary of the Invention

[0003] The present invention addresses the difficulty in producing Micro LEDs of different colors in high-resolution display panels and provides a display panel that not only enables full-color display but also reduces the difficulty of producing different-color light-emitting elements and improves the yield of these elements.

[0004] The present invention provides a display panel, comprising: a driving backplane,

[0005] A plurality of light-emitting elements are located on one side of the driving backplane and arranged in an array, wherein the plurality of light-emitting elements emit blue light;

[0006] a quantum dot material layer, located on a side of the light-emitting element away from the driving backplane;

[0007] a color conversion layer, located on a side of the quantum dot material layer away from the driving backplane, capable of enabling the multiple light-emitting elements to achieve color display;

[0008] The orthographic projections of the color conversion layer and the quantum dot material layer on the driving backplane at least cover the orthographic projection of the light-emitting element on the driving backplane;

[0009] The quantum dot material layer includes red quantum dot material and green quantum dot material, and the quantum dot material layer can convert the blue light emitted by the light emitting element into white light.

[0010] In some embodiments, the mass percentage ratio of the red quantum dot material to the green quantum dot material in the quantum dot material layer is in a range of 1:2 to 1:10;

[0011] The total mass percentage of the red quantum dot material and the green quantum dot material in the quantum dot material layer is in the range of 30% to 60%;

[0012] The quantum dot material layer also includes scattering particles,

[0013] The mass percentage of the scattering particles in the quantum dot material layer is in the range of 1% to 15%;

[0014] The diameter of the scattering particles ranges from 50 to 500 nm.

[0015] In some embodiments, the quantum dot material layer includes a plurality of first sub-portions,

[0016] The plurality of first sub-portions correspond to the plurality of light-emitting elements one by one, and the orthographic projections of the plurality of first sub-portions on the driving backplane do not overlap with each other.

[0017] In some embodiments, the orthographic projection of the quantum dot material layer on the driving backplane covers the driving backplane.

[0018] In some embodiments, an encapsulation layer and a protective layer are further included to prevent water and oxygen from entering the quantum dot material layer;

[0019] The encapsulation layer is located on a side of the quantum dot material layer close to the light emitting element, and covers the bottom surface of the quantum dot material layer close to the light emitting element;

[0020] The protective layer is located on a side of the quantum dot material layer away from the light-emitting element, and covers the top surface and side surfaces of the quantum dot material layer away from the light-emitting element;

[0021] The top surface and the bottom surface of the quantum dot material layer are opposite to each other.

[0022] In some embodiments, the material of the encapsulation layer includes silicon nitride;

[0023] The thickness of the encapsulation layer ranges from 100 to 300 nm;

[0024] The protective layer includes a plurality of silicon nitride layers and a plurality of silicon carbonitride layers, wherein the silicon nitride layers and the silicon carbonitride layers are alternately stacked in sequence;

[0025] The thickness of the silicon nitride layer is in the range of 100 to 300 nm, and the thickness of the silicon carbonitride layer is in the range of 100 to 300 nm.

[0026] In some embodiments, a first metal light-shielding layer is further included, covering the top edge and side surfaces of the quantum dot material layer and being located on a side of the protective layer away from the quantum dot material layer.

[0027] In some embodiments, a second metal light shielding layer is further included, covering the top edge and side surface of the light emitting element away from the driving backplane.

[0028] The top surface of the light emitting element is opposite to the top surface of the quantum dot material layer.

[0029] In some embodiments, the width of the edge of the top surface of the quantum dot material layer covered by the first metal light-shielding layer is in the range of 0.1 to 0.5 μm;

[0030] The width of the second metal light-shielding layer covering the edge of the top surface of the light-emitting element is in the range of 0.1 to 0.5 μm.

[0031] In some embodiments, a first flat layer is further included, which is in the same layer as the light-emitting elements and is located between any adjacent light-emitting elements and at the periphery of the array of light-emitting elements.

[0032] The orthographic projections of the first planar layer and the light-emitting element on the driving backplane do not overlap;

[0033] The first planar layer is made of a resin material or an organic silicon material mixed with black dye.

[0034] In some embodiments, a distance between a surface of the first planar layer facing away from the driving backplane and the driving backplane is less than or equal to a distance between a surface of the light-emitting element facing away from the driving backplane and the driving backplane;

[0035] The display panel further includes a second flat layer located on a side of the light-emitting element and the first flat layer away from the driving backplane and a side of the encapsulation layer close to the driving backplane, wherein the orthographic projection of the second flat layer on the driving backplane covers the driving backplane;

[0036] The distance between any point on the surface of the second flat layer on the side facing away from the driving back plate and the driving back plate is equal;

[0037] The second flat layer is made of transparent resin material.

[0038] In some embodiments, a distance between a surface of the first planar layer facing away from the driving backplane and the driving backplane is smaller than a distance between a surface of the light-emitting element facing away from the driving backplane and the driving backplane;

[0039] The display panel further includes a plurality of first spacers, the plurality of first spacers being evenly distributed on a side of the first planar layer facing away from the driving backplane, and the orthographic projections of the first spacers on the driving backplane being located within an orthographic projection area of the first planar layer on the driving backplane;

[0040] The distance between the driving backplate and a surface of the first spacer facing away from the driving backplate is less than or equal to the distance between the driving backplate and a surface of the light-emitting element facing away from the driving backplate.

[0041] In some embodiments, a plurality of second spacers are further included, which are in the same layer as the light-emitting elements and are evenly distributed between any adjacent light-emitting elements and around the periphery of the array of light-emitting elements.

[0042] The orthographic projections of the second spacer and the light emitting element on the driving backplane do not overlap;

[0043] The distance between the driving backplate and a surface of the second spacer facing away from the driving backplate is less than or equal to the distance between the driving backplate and a surface of the light-emitting element facing away from the driving backplate.

[0044] In some embodiments, a surface of the first planar layer facing away from the driving backplane is flush with a surface of the light-emitting element facing away from the driving backplane.

[0045] The encapsulation layer also extends to cover the first planar layer,

[0046] A surface of the first planar layer facing away from the driving backplane and a surface of the light-emitting element facing away from the driving backplane are in contact with the encapsulation layer respectively.

[0047] In some embodiments, a surface of the first planar layer facing away from the driving back plate is flush with a surface of the protective layer covering the top surface of the quantum dot material layer facing away from the driving back plate;

[0048] The display panel further includes a third flat layer located on a side of the first flat layer and the protective layer away from the driving backplane, and located on a side of the color conversion layer close to the driving backplane;

[0049] The orthographic projection of the third flat layer on the driving backplane covers the driving backplane;

[0050] The distance between any point on the surface of the third flat layer on the side facing away from the driving back plate and the driving back plate is equal.

[0051] In some embodiments, the color conversion layer includes a black matrix and a plurality of second sub-portions.

[0052] The black matrix and the plurality of second sub-sections are in the same layer;

[0053] The plurality of second sub-sections are arranged in an array, and the black matrix is located between any adjacent second sub-sections and on the periphery of the array of the second sub-sections;

[0054] The plurality of second sub-portions correspond one-to-one to the plurality of light-emitting elements, and the orthographic projections of the second sub-portions on the driving backplane cover the orthographic projections of the light-emitting elements on the driving backplane.

[0055] In some embodiments, the second subsection includes a first color resist or a grating.

[0056] In some embodiments, the colors of the first color resist include red, green and blue.

[0057] Along the row direction or column direction of the array of the light-emitting elements, the colors of the first color resists corresponding to any three adjacent light-emitting elements are different;

[0058] The period of the grating includes a first period, a second period and a third period;

[0059] The range of the first cycle is 430-470; the range of the second cycle is 400-430; the range of the third cycle is 360-390;

[0060] Along the row direction or column direction of the array of the light emitting elements, the periods of the gratings corresponding to any three adjacent light emitting elements are different.

[0061] In some embodiments, a light extraction layer is further included, located on a side of the color conversion layer away from the driving backplane;

[0062] The light extraction layer includes a plurality of third sub-portions, and the plurality of third sub-portions are arranged in an array.

[0063] The plurality of third sub-portions correspond one-to-one to the plurality of second sub-portions, and the orthographic projections of the third sub-portions on the driving backplane cover the orthographic projections of the second sub-portions on the driving backplane.

[0064] In some embodiments, the second subsection comprises a grating,

[0065] The display panel further includes a plurality of second color resists located on a side of the color conversion layer away from the driving backplane, and the plurality of second color resists are arranged in an array;

[0066] The plurality of second color resists correspond to the plurality of second sub-portions one by one, and the orthographic projection of the second color resist on the driving backplane covers the orthographic projection of the second sub-portion on the driving backplane;

[0067] The color of the second color resist is the same as the light output color of the corresponding second sub-section.

[0068] Beneficial effects of the present invention: The display panel provided by the present invention converts the blue light emitted by the light-emitting element into white light by setting a quantum dot material layer including red quantum dot material and green quantum dot material, and realizes color display of multiple light-emitting elements by setting a color conversion layer. It can not only realize the full-color display of the display panel, but also reduce the difficulty of the preparation process of light-emitting elements of different colors and improve the yield of light-emitting elements of different colors. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] Figure 1 Schematic diagram of a partial cross-sectional structure of a Micro LED display panel in the related art;

[0070] Figure 2 is a schematic cross-sectional view of a partial structure of a display panel according to an embodiment of the present invention;

[0071] Figure 3a is a schematic cross-sectional view of a partial structure of another display panel according to an embodiment of the present invention;

[0072] Figure 3b for Figure 3a A schematic cross-sectional view of the local structure of the upper and middle substrates;

[0073] Figure 3c for Figure 3a A schematic cross-sectional view of the local structure of the middle and lower substrates;

[0074] Figure 4 is a schematic cross-sectional view of a partial structure of another display panel according to an embodiment of the present invention;

[0075] Figure 5a is a schematic cross-sectional view of a partial structure of another display panel according to an embodiment of the present invention;

[0076] Figure 5b for Figure 5a A schematic cross-sectional view of the local structure of the upper and middle substrates;

[0077] Figure 5c for Figure 5a A schematic cross-sectional view of the local structure of the middle and lower substrates;

[0078] Figure 6 is a schematic cross-sectional view of a partial structure of another display panel according to an embodiment of the present invention;

[0079] Figure 7 FIG2 is a schematic cross-sectional view of a partial structure of another display panel according to an embodiment of the present invention. DETAILED DESCRIPTION

[0080] In order to enable those skilled in the art to better understand the technical solution of the present invention, a display panel of the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0081] In one embodiment of the related art, in a Micro LED display panel, the main problem of the Micro LED display device is that the process maturity of Micro LEDs of different colors is different, and the yield rate will be greatly reduced if Micro LEDs of different colors are transferred simultaneously.

[0082] In another embodiment of the related art, a high-resolution Micro LED display panel uses blue Micro LEDs as the backlight, and a color conversion layer (such as a quantum dot color conversion layer) is fabricated on the light-emitting side of the Micro LED to achieve color display. The quantum dot color conversion layer requires a relatively large thickness. Due to the reduced size of the Micro LED device at high resolution, the aspect ratio of the quantum dot color conversion layer increases, making the fabrication process difficult. Furthermore, due to the reduced spacing between Micro LED devices, the light-blocking layer between the Micro LED devices is difficult to fabricate.

[0083] like Figure 1 As shown, the color conversion layer 4 in the related art includes a red quantum dot material layer 43, a green quantum dot material layer 44, and a diffusion particle layer 45. The red quantum dot material layer 43, the green quantum dot material layer 44, and the diffusion particle layer 45 correspond to different blue Micro LEDs 17, respectively. When the color conversion layer 4 is produced by exposure and development, two exposure and development processes are required to form the pattern of the red quantum dot material layer 43 and the pattern of the green quantum dot material layer 44, respectively. The preparation process is relatively complicated; moreover, the latter exposure and development process may damage the pattern of the quantum dot material layer formed in the previous one. At the same time, the exposure and development process will cause material waste. When produced by inkjet printing, especially when preparing micro LED panels with higher resolution, the micro LED devices are particularly small and the ink droplet size is relatively large, which cannot be matched by the printing process.

[0084] In order to solve the problem of difficulty in preparing Micro LEDs of different colors in high-resolution display panels, an embodiment of the present invention provides a display panel such as Figure 2 、 Figure 3a 、 Figure 3b 、 Figure 3c 、 Figure 4 、 Figure 5a 、 Figure 5b 、 Figure 5c 、 Figure 6 and Figure 7As shown, it includes: a driving backplane 1, a plurality of light-emitting elements 2, which are located on one side of the driving backplane 1 and arranged in an array, and the plurality of light-emitting elements 2 emit blue light; a quantum dot material layer 3, which is located on the side of the light-emitting element 2 away from the driving backplane 1; a color conversion layer 4, which is located on the side of the quantum dot material layer 3 away from the driving backplane 1, and can enable the plurality of light-emitting elements 2 to achieve color display; the orthographic projections of the color conversion layer 4 and the quantum dot material layer 3 on the driving backplane 1 at least cover the orthographic projections of the light-emitting element 2 on the driving backplane 1; the quantum dot material layer 3 includes red quantum dot material and green quantum dot material, and the quantum dot material layer 3 can convert the blue light emitted by the light-emitting element 2 into white light.

[0085] The light-emitting element 2 can be a Micro LED device or a Mini LED device. In this embodiment, a Micro LED device is used as an example. The size of the Micro LED device is less than 50 μm, and the size of the Mini LED device is between 50 and 200 μm. The thickness of the light-emitting element 2 is approximately 2 to 5 μm, and the wavelength of the blue light emitted by the light-emitting element 2 is within the range of 440 to 480 nm. The driver backplane 1 uses a traditional Micro LED driver substrate. The driver backplane 1 will not be described in detail here.

[0086] In this embodiment, the quantum dot material layer 3 including red quantum dot material and green quantum dot material emits yellow light under the stimulation of the light emitted by the light-emitting element 2. The yellow light is mixed with the blue light emitted by the light-emitting element 2 to form white light. Therefore, in this embodiment, the quantum dot material layer 3 can convert the blue light emitted by the light-emitting element 2 into white light; the color conversion layer 4 can filter the white light in different bands, thereby realizing the color display of the display panel.

[0087] In this embodiment, a quantum dot material layer 3 including red quantum dot material and green quantum dot material is provided to convert the blue light emitted by the light-emitting element 2 into white light, and a color conversion layer 4 is provided to achieve color display of multiple light-emitting elements 2. This not only enables full-color display of the display panel, but also reduces the difficulty of the preparation process of light-emitting elements 2 of different colors, thereby improving the yield of light-emitting elements 2 of different colors.

[0088] In some embodiments, the mass percentage ratio of the red quantum dot material and the green quantum dot material in the quantum dot material layer 3 ranges from 1:2 to 1:10; the total mass percentage of the red quantum dot material and the green quantum dot material in the quantum dot material layer 3 ranges from 30% to 60%; the quantum dot material layer 3 also includes scattering particles, and the mass percentage of the scattering particles in the quantum dot material layer 3 ranges from 1% to 15%; the diameter of the scattering particles ranges from 50 to 500 nm.

[0089] The wavelength of light emitted by the red quantum dot material after being stimulated by energy is in the range of 620 to 650 nm, and the half-peak width of the spectrum of the wavelength band in which the red quantum dot material emits light after being stimulated by energy is in the range of 20 to 35 nm. The wavelength of light emitted by the green quantum dot material after being stimulated by energy is in the range of 520 to 550 nm, and the half-peak width of the spectrum of the wavelength band in which the green quantum dot material emits light after being stimulated by energy is in the range of 20 to 35 nm. Scattering particles such as titanium oxide or silicon oxide scattering particles are used. The quantum dot material layer 3 can achieve an external quantum efficiency (EQE) of 20% to 80%. The blue light emitted by the light-emitting element 2 after passing through the quantum dot material layer 3 can achieve a color coordinate range of x (0.27 to 0.35) and y (0.27 to 0.35).

[0090] In some embodiments, as Figure 2-5a As shown, the quantum dot material layer 3 includes multiple first sub-sections 30, each corresponding one-to-one to the multiple light-emitting elements 2. The orthographic projections of the multiple first sub-sections 30 on the driver backplane 1 do not overlap. This arrangement allows the quantum dot material layer 3 to be formed through a single exposure process (including film coating, exposure, and development steps), simplifying the preparation process. This also avoids the complex process, pattern damage, and material waste associated with forming the red and green quantum dot material layers separately through two exposure processes in the related art.

[0091] In some embodiments, as Figure 6-Figure 7 As shown, the orthographic projection of the quantum dot material layer 3 on the driver backplane 1 covers the driver backplane 1. This arrangement allows the quantum dot material layer 3 to be prepared by a single material coating, eliminating the need for an exposure process. This simplifies the preparation process, reduces the difficulty of the preparation process, and also saves materials.

[0092] In some embodiments, as Figure 2-Figure 7 As shown, the display panel also includes an encapsulation layer 5 and a protective layer 6, which are used to prevent water and oxygen from entering the quantum dot material layer 3; the encapsulation layer 5 is located on the side of the quantum dot material layer 3 close to the light-emitting element 2, and covers the bottom surface of the quantum dot material layer 3 close to the light-emitting element 2; the protective layer 6 is located on the side of the quantum dot material layer 3 away from the light-emitting element 2, and covers the top surface and side surface of the quantum dot material layer 3 away from the light-emitting element 2; the top surface and bottom surface of the quantum dot material layer 3 are opposite.

[0093] In some embodiments, the material of the encapsulation layer 5 includes silicon nitride; the thickness of the encapsulation layer 5 ranges from 100 to 300 nm; the protective layer 6 includes multiple silicon nitride layers and multiple silicon carbonitride layers, and the silicon nitride layers and the silicon carbonitride layers are alternately stacked in sequence; the thickness of the silicon nitride layer ranges from 100 to 300 nm, and the thickness of the silicon carbonitride layer ranges from 100 to 300 nm.

[0094] The main function of the encapsulation layer 5 is to increase the wettability of the bottom of the quantum dot material layer 3 while preventing water and oxygen from entering the quantum dot material layer 3. The refractive index of the encapsulation layer 5 is approximately 1.7, and the transmittance is above 95%. The protective layer 6 can be an alternating stack of two silicon nitride layers and one silicon carbonitride layer, with the thicknesses of the three layers being 300nm / 100nm / 300nm respectively. Alternatively, the protective layer 6 can be an alternating stack of three silicon nitride layers and two silicon carbonitride layers, with the thicknesses of the five layers being 200nm / 100nm / 100nm / 100nm / 200nm respectively.

[0095] In some embodiments, as Figure 2-Figure 7 As shown, the display panel further includes a first metal light-shielding layer 7, which covers the top edge and side surfaces of the quantum dot material layer 3 and is located on the side of the protective layer 6 facing away from the quantum dot material layer 3. The first metal light-shielding layer 7 can reflect light that impinges on the side surfaces of the quantum dot material layer 3 back into the interior of the quantum dot material layer 3, preventing light that impinges on the top edge and side surfaces of the quantum dot material layer 3 from diffusing and being lost in all directions. This prevents cross-color interference between adjacent light-emitting elements 2, improves the light extraction efficiency of the light emitted by the quantum dot material layer 3, and further improves the utilization efficiency of the light emitted by the light-emitting elements 2 and the light emitted by the quantum dot material layer 3.

[0096] In some embodiments, as Figure 2-Figure 7 As shown, the display panel further includes a second metal light-shielding layer 8, which covers the top edge and side surface of the light-emitting element 2 facing away from the driver backplane 1. The top surface of the light-emitting element 2 is opposite the top surface of the quantum dot material layer 3. The second metal light-shielding layer 8 can reflect light that impinges on the side of the light-emitting element 2 back to the light-emitting side of the top surface of the light-emitting element 2, preventing light that impinges on the top edge and side surface of the light-emitting element 2 from diffusing and being lost in all directions. This prevents cross-color interference between adjacent light-emitting elements 2, improves the light extraction efficiency of the light-emitting element 2, and further improves the utilization rate of the light emitted by the light-emitting element 2.

[0097] In some embodiments, the first metal light-shielding layer 7 and the second metal light-shielding layer 8 are made of a metal with a high reflectivity such as silver Ag or aluminum Al, with a reflectivity of more than 90%. Metal materials with good stability such as molybdenum Mo can also be used. The thickness range of the first metal light-shielding layer 7 and the second metal light-shielding layer 8 is 200 to 500 nm. The width range of the top edge of the first metal light-shielding layer 7 covering the quantum dot material layer 3 is 0.1 to 0.5 μm. The width range of the top edge of the second metal light-shielding layer 8 covering the light-emitting element 2 is 0.1 to 0.5 μm. The first metal light-shielding layer 7 and the second metal light-shielding layer 8 can both be formed by sputtering and then etched to form the desired pattern.

[0098] In some embodiments, as Figure 2-Figure 4 , Figure 6-Figure 7As shown, the display panel also includes a first planar layer 9, which is co-layered with the light-emitting elements 2 and located between any adjacent light-emitting elements 2 and around the periphery of the array of light-emitting elements 2. The orthographic projections of the first planar layer 9 and the light-emitting elements 2 on the driver backplane 1 do not overlap. The first planar layer 9 is made of a resin material or silicone material doped with black dye. The first planar layer 9 prevents cross-color interference between adjacent light-emitting elements 2.

[0099] In some embodiments, the first flat layer 9 is made of a resin material with good fluidity, such as epoxy resin or acrylic resin. The first flat layer 9 can also be made of silicone material to improve the temperature resistance of the material. The first flat layer 9 is prepared by the process of material coating, exposure, and development. During preparation, the viscosity of the material of the first flat layer 9 is between 3 and 20 cps. A certain amount of black dye can be added thereto to make it have a certain light absorption, thereby preventing light leakage from the light-emitting element 2. The first flat layer 9 is in contact with adjacent light-emitting elements 2, and the filling width of the first flat layer 9 between adjacent light-emitting elements 2 is 1 to 8 μm. During the preparation process, the material of the first flat layer 9 covering the light-emitting element 2 is removed by development, and the material of the first flat layer 9 located between adjacent light-emitting elements 2 is cured by light.

[0100] In some embodiments, as Figure 2 、 Figure 6 and Figure 7 As shown, the overall thickness of the first planar layer 9 is close to the height of the light emitting element 2 , which is approximately 2 to 5 μm.

[0101] In some embodiments, as Figure 2 As shown, the distance between the surface of the first flat layer 9 on the side facing away from the driving backplane 1 and the driving backplane 1 is less than or equal to the distance between the surface of the light-emitting element 2 on the side facing away from the driving backplane 1 and the driving backplane 1; the display panel also includes a second flat layer 10, which is located on the side of the light-emitting element 2 and the first flat layer 9 facing away from the driving backplane 1 and the side of the encapsulation layer 5 close to the driving backplane 1, and the orthographic projection of the second flat layer 10 on the driving backplane 1 covers the driving backplane 1; the distance between any point on the surface of the second flat layer 10 on the side facing away from the driving backplane 1 and the driving backplane 1 is equal; the second flat layer 10 is made of transparent resin material.

[0102] In some embodiments, the second flat layer 10 is made of an organic material with a transmittance of 95% or more in the visible light band (450-800 nm) and a temperature tolerance range of 80-250°C; for example, the second flat layer 10 is made of acrylic resin or epoxy resin. The overall thickness of the second flat layer 10 is 0.2-1 μm. The main function of the second flat layer 10 is to perform secondary flattening on the basis of the first flat layer 9. Unlike the preparation process of the first flat layer 9, after the second flat layer 10 material is applied, it needs to be rolled using a nanoimprinting device to increase the flatness of the surface facing away from the driver backplane 1. The actual principle of increasing its surface flatness is that rolling using the nanoimprinting device can change the surface conformality (i.e., the surface has bumps) of the second flat layer 10 facing away from the driver backplane 1, making the surface of the second flat layer 10 facing away from the driver backplane 1 more flat, so as to better prepare the quantum dot material layer 3 on the flat surface of the second flat layer 10.

[0103] In some embodiments, as Figure 3a-3c As shown, the distance between the surface of the first flat layer 9 facing away from the driving backplane 1 and the driving backplane 1 is less than the distance between the surface of the light-emitting element 2 facing away from the driving backplane 1 and the driving backplane 1; the display panel also includes a plurality of first spacers 11, and the plurality of first spacers 11 are evenly distributed on the side of the first flat layer 9 facing away from the driving backplane 1, and the orthographic projections of the first spacers 11 on the driving backplane 1 are located within the orthographic projection area of the first flat layer 9 on the driving backplane 1; the distance between the surface of the first spacer 11 facing away from the driving backplane 1 and the driving backplane 1 is less than or equal to the distance between the surface of the light-emitting element 2 facing away from the driving backplane 1 and the driving backplane 1.

[0104] In some embodiments, the first spacer 11 can be made of acrylic resin material, and the height of the first spacer 11 ranges from 2 to 5 μm. The shape of the first spacer 11 can be a truncated cone, such as a circular truncated cone, and the diameter of the first spacer 11 ranges from 0.5 to 2 μm. The first spacer 11 is used to support the cassette substrate. The first spacer 11 is prepared by a traditional exposure process (including film coating, exposure, development, etc.). The specific preparation process is not repeated here.

[0105] In some embodiments, as Figure 4As shown, the surface of the first flat layer 9 facing away from the driver backplane 1 is flush with the surface of the protective layer 6 covering the top surface of the quantum dot material layer 3 facing away from the driver backplane 1. The display panel also includes a third flat layer 12, located on the side of the first flat layer 9 and protective layer 6 facing away from the driver backplane 1, and on the side of the color conversion layer 4 close to the driver backplane 1. The orthographic projection of the third flat layer 12 on the driver backplane 1 covers the driver backplane 1. The distance between any point on the surface of the third flat layer 12 facing away from the driver backplane 1 is equal to that of the driver backplane 1. This arrangement facilitates the preparation of the color conversion layer 4 on the flat surface of the third flat layer 12.

[0106] In some embodiments, the third flat layer 12 is made of a transparent resin material, such as acrylic resin or epoxy resin, and has a thickness ranging from 1 to 2 μm.

[0107] In some embodiments, as Figure 6 and Figure 7 As shown, the surface of the first flat layer 9 facing away from the driving backplane 1 and the surface of the light-emitting element 2 facing away from the driving backplane 1 are flush, and the encapsulation layer 5 also extends to cover the first flat layer 9, and the surface of the first flat layer 9 facing away from the driving backplane 1 and the surface of the light-emitting element 2 facing away from the driving backplane 1 are respectively in contact with the encapsulation layer 5.

[0108] In some embodiments, as Figure 5a-5c As shown, the display panel also includes a plurality of second spacers 13, which are in the same layer as the light-emitting elements 2 and are evenly distributed between any adjacent light-emitting elements 2 and on the periphery of the array of light-emitting elements 2. The orthographic projections of the second spacers 13 and the light-emitting elements 2 on the driving backplane 1 do not overlap; the distance between the side surface of the second spacer 13 facing away from the driving backplane 1 and the driving backplane 1 is less than or equal to the distance between the side surface of the light-emitting element 2 facing away from the driving backplane 1 and the driving backplane 1.

[0109] In some embodiments, the second spacer 13 can be made of acrylic resin material, and the height of the second spacer 13 ranges from 5 to 8 μm. The shape of the second spacer 13 can be a truncated cone, such as a circular truncated cone, and the diameter of the second spacer 13 ranges from 0.5 to 2 μm. The second spacer 13 is used to support the cassette substrate. The second spacer 13 is prepared by a conventional exposure process (including film coating, exposure, development, etc.). The specific preparation process is not repeated here.

[0110] In this embodiment, Figure 5a As shown, the first flat layer is not provided in the display panel, and the support of the cell substrate is achieved by providing a second spacer 13 .

[0111] In some embodiments, as Figure 2-Figure 7As shown, the color conversion layer 4 includes a black matrix 41 and a plurality of second sub-sections 42, and the black matrix 41 and the plurality of second sub-sections 42 are in the same layer; the plurality of second sub-sections 42 are arranged in an array, and the black matrix 41 is located between any adjacent second sub-sections 42 and at the periphery of the array of the second sub-sections 42; the plurality of second sub-sections 42 correspond one-to-one to the plurality of light-emitting elements 2, and the orthographic projection of the second sub-sections 42 on the driving backplane 1 covers the orthographic projection of the light-emitting element 2 on the driving backplane 1.

[0112] In some embodiments, the main function of the black matrix 41 is to fill the grooves between adjacent stacked layers formed by the second sub-section 42 and the quantum dot material layer 3, which can provide a flattening effect. The black matrix 41 can also block possible side light leakage from adjacent stacked layers to prevent cross-color interference between adjacent light-emitting elements 2. The thickness of the black matrix 41 ranges from 2 to 5 μm.

[0113] In some embodiments, as Figure 2 、 Figure 3a and Figure 5a As shown, the second subsection 42 includes a first color resist; or Figure 4 、 Figure 6 and Figure 7 As shown, the second subsection 42 comprises a grating.

[0114] In some embodiments, the colors of the first color resist include red, green, and blue, and along the row direction or column direction of the array of light-emitting elements 2, the colors of the first color resist corresponding to any three adjacent light-emitting elements 2 are different; the period of the grating includes a first period, a second period, and a third period; the range of the first period is 430 to 470; the range of the second period is 400 to 430; the range of the third period is 360 to 390; along the row direction or column direction of the array of light-emitting elements 2, the period of the grating corresponding to any three adjacent light-emitting elements 2 is different.

[0115] Among them, the main function of the first color resist is to filter out light of a different color from the first color resist in white light. The transmittance wavelength of the green first color resist material is 500-560nm, the transmittance wavelength of the red first color resist material is 580-650nm, and the transmittance wavelength of the blue first color resist material is 450-490nm. The three adjacent light-emitting elements 2 corresponding to the red, green and blue first color resists constitute a pixel, and the first color resists of the three colors can realize the color display of the pixel, thereby realizing the color display of the display panel. The thickness range of the first color resist is 1.0-1.5μm,

[0116] In some embodiments, the period of the grating is different, and the wavelength of light passing through the grating is also different, that is, only light of a specific wavelength can pass through the grating of a specific period. The function of gratings of different periods is the same as that of first color resists of different colors. The principle of gratings of different periods passing light of a specific wavelength is: n0sinθc=n1sin 90°; θc=arcsin(n1 / n0). n0 is the refractive index of the protective layer 6, n1 is the refractive index of the grating, θc is the incident angle of the light from the protective layer 6 to the grating; 90° is the exit angle of the light from the grating; that is, light incident from the protective layer 6 to the grating that satisfies n0sinθc=n1sin 90° can pass through the grating. Among them, n0 is 1.3~1.5, and n1 is 1.8~2.5. By setting the period of the grating to be different, the wavelength of light passing through the grating can be made different; the grating of the third period can pass blue light, the grating of the second period can pass green light, and the grating of the first period can pass red light. Three adjacent light emitting elements 2 corresponding to the first period, the second period and the third period gratings constitute a pixel. The three periods of gratings can realize color display of the pixel, thereby realizing color display of the display panel.

[0117] In some embodiments, the grating is made of acrylic resin, has a thickness ranging from 70 to 100 nm, and a duty cycle of 0.5, and is fabricated by nanoimprinting.

[0118] In some embodiments, as Figure 3a and Figure 5a As shown, the color conversion layer 4 can be set on one side of the glass cover plate 16, and the glass cover plate 16 is made of high-transmittance glass with a transmittance of 99.9%. The display panel can be formed by assembling an upper substrate and a lower substrate. The upper substrate includes the color conversion layer 4 and the glass cover plate 16; the lower substrate includes the light-emitting element 2, the quantum dot material layer 3 and the driving backplane 1. During the assembly, a filler is applied to the upper substrate side or the lower substrate side, and the black matrix 41 on the upper substrate side corresponds to the groove where the first spacer 11 or the second spacer 13 on the lower substrate side is located. Since there is a large gap at the position of the first spacer 11 or the second spacer 13, the excess filler can be filled into the gap during the assembly process.

[0119] In some embodiments, as Figure 2 As shown, the display panel also includes a light extraction layer 14, which is located on the side of the color conversion layer 4 away from the driving backplane 1; the light extraction layer 14 includes a plurality of third sub-sections 140, and the plurality of third sub-sections 140 are arranged in an array, and the plurality of third sub-sections 140 correspond one-to-one to the plurality of second sub-sections 42, and the orthographic projection of the third sub-section 140 on the driving backplane 1 covers the orthographic projection of the second sub-section 42 on the driving backplane 1.

[0120] In some embodiments, the light extraction layer 14 is made of a transparent organic material with a refractive index of 2.0 or higher, such as an organic silicon material. The function of the light extraction layer 14 is to increase the extraction of light passing through the color conversion layer 4 .

[0121] In some embodiments, as Figure 7 As shown, the second sub-section 42 includes a grating, and the display panel also includes a plurality of second color resists 15, which are located on the side of the color conversion layer 4 away from the driving backplane 1, and the plurality of second color resists 15 are arranged in an array; the plurality of second color resists 15 correspond one-to-one to the plurality of second sub-sections 42, and the orthographic projection of the second color resist 15 on the driving backplane 1 covers the orthographic projection of the second sub-section 42 on the driving backplane 1; the color of the second color resist 15 is the same as the light output color of the corresponding second sub-section 42.

[0122] The second color resist 15 includes red, green, and blue. The green second color resist has a transmittance wavelength of 500-560nm, the red second color resist has a transmittance wavelength of 580-650nm, and the blue second color resist has a transmittance wavelength of 450-490nm. The primary function of the second color resist 15 is to further optimize the wavelength band of emitted light.

[0123] The preparation of each film layer in the display panel of this embodiment adopts relatively mature traditional processes, which will not be described in detail here.

[0124] The display panel provided in this embodiment converts the blue light emitted by the light-emitting element into white light by providing a quantum dot material layer including red quantum dot material and green quantum dot material, and realizes color display of multiple light-emitting elements by providing a color conversion layer. This not only enables full-color display of the display panel, but also reduces the difficulty of the preparation process of light-emitting elements of different colors and improves the yield of light-emitting elements of different colors.

[0125] The display panel can be: Micro LED panel, Micro LED TV, Mini LED panel, electronic paper, mobile phone, tablet computer, laptop computer, monitor, notebook computer, digital photo frame, navigator, or any other product or component with display function.

[0126] It will be understood that the above embodiments are merely exemplary embodiments for illustrating the principles of the present invention, and the present invention is not limited thereto. Those skilled in the art will appreciate that various modifications and improvements can be made without departing from the spirit and substance of the present invention, and such modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A display panel, comprising: Drive backplane, A plurality of light-emitting elements are located on one side of the driving backplane and arranged in an array, wherein the plurality of light-emitting elements emit blue light; a quantum dot material layer, located on a side of the light-emitting element away from the driving backplane; a color conversion layer, located on a side of the quantum dot material layer away from the driving backplane, capable of enabling the multiple light-emitting elements to achieve color display; The orthographic projections of the color conversion layer and the quantum dot material layer on the driving backplane at least cover the orthographic projection of the light-emitting element on the driving backplane; It is characterized in that the quantum dot material layer includes red quantum dot material and green quantum dot material, and the quantum dot material layer can convert the blue light emitted by the light emitting element into white light.

2. The display panel according to claim 1, wherein: The mass percentage ratio of the red quantum dot material to the green quantum dot material in the quantum dot material layer is in the range of 1:2 to 1:10; The total mass percentage of the red quantum dot material and the green quantum dot material in the quantum dot material layer is in the range of 30% to 60%; The quantum dot material layer also includes scattering particles, The mass percentage of the scattering particles in the quantum dot material layer is in the range of 1% to 15%; The diameter of the scattering particles ranges from 50 to 500 nm.

3. The display panel according to claim 2, wherein: The quantum dot material layer includes a plurality of first sub-portions, The plurality of first sub-portions correspond to the plurality of light-emitting elements one by one, and the orthographic projections of the plurality of first sub-portions on the driving backplane do not overlap with each other.

4. The display panel according to claim 2, wherein: The orthographic projection of the quantum dot material layer on the driving backplane covers the driving backplane.

5. The display panel according to claim 3 or 4, characterized in that: It also includes an encapsulation layer and a protective layer for preventing water and oxygen from entering the quantum dot material layer; The encapsulation layer is located on a side of the quantum dot material layer close to the light emitting element, and covers the bottom surface of the quantum dot material layer close to the light emitting element; The protective layer is located on a side of the quantum dot material layer away from the light-emitting element, and covers the top surface and side surfaces of the quantum dot material layer away from the light-emitting element; The top surface and the bottom surface of the quantum dot material layer are opposite to each other.

6. The display panel according to claim 5, wherein: The material of the encapsulation layer includes silicon nitride; The thickness of the encapsulation layer ranges from 100 to 300 nm; The protective layer includes a plurality of silicon nitride layers and a plurality of silicon carbonitride layers, wherein the silicon nitride layers and the silicon carbonitride layers are alternately stacked in sequence; The thickness of the silicon nitride layer is in the range of 100 to 300 nm, and the thickness of the silicon carbonitride layer is in the range of 100 to 300 nm.

7. The display panel according to claim 5, wherein: It also includes a first metal light-shielding layer, which covers the top edge and side surfaces of the quantum dot material layer and is located on a side of the protective layer away from the quantum dot material layer.

8. The display panel according to claim 7, wherein: It also includes a second metal light-shielding layer, covering the top edge and side surface of the light-emitting element away from the driving backplane, The top surface of the light emitting element is opposite to the top surface of the quantum dot material layer.

9. The display panel according to claim 8, wherein: The width of the edge of the top surface of the quantum dot material layer covered by the first metal light-shielding layer is in the range of 0.1 to 0.5 μm; The width of the second metal light-shielding layer covering the edge of the top surface of the light-emitting element is in the range of 0.1 to 0.5 μm.

10. The display panel according to claim 5, wherein: It also includes a first flat layer, which is in the same layer as the light-emitting elements and is located between any adjacent light-emitting elements and around the periphery of the array of light-emitting elements. The orthographic projections of the first planar layer and the light-emitting element on the driving backplane do not overlap; The first planar layer is made of a resin material or an organic silicon material mixed with black dye.

11. The display panel according to claim 10, wherein: The distance between the driving backplane and a surface of the first planar layer facing away from the driving backplane is less than or equal to the distance between the driving backplane and a surface of the light-emitting element facing away from the driving backplane; The display panel further includes a second flat layer located on a side of the light-emitting element and the first flat layer away from the driving backplane and a side of the encapsulation layer close to the driving backplane, wherein the orthographic projection of the second flat layer on the driving backplane covers the driving backplane; The distance between any point on the surface of the second flat layer on the side facing away from the driving back plate and the driving back plate is equal; The second flat layer is made of transparent resin material.

12. The display panel according to claim 10, wherein: The distance between the driving backplane and a surface of the first flat layer facing away from the driving backplane is smaller than the distance between the driving backplane and a surface of the light-emitting element facing away from the driving backplane; The display panel further includes a plurality of first spacers, the plurality of first spacers being evenly distributed on a side of the first planar layer facing away from the driving backplane, and the orthographic projections of the first spacers on the driving backplane being located within an orthographic projection area of the first planar layer on the driving backplane; The distance between the driving backplate and a surface of the first spacer facing away from the driving backplate is less than or equal to the distance between the driving backplate and a surface of the light-emitting element facing away from the driving backplate.

13. The display panel according to claim 5, wherein: It also includes a plurality of second spacers, which are in the same layer as the light-emitting elements and are evenly distributed between any adjacent light-emitting elements and around the periphery of the array of light-emitting elements. The orthographic projections of the second spacer and the light emitting element on the driving backplane do not overlap; The distance between the driving backplate and a surface of the second spacer facing away from the driving backplate is less than or equal to the distance between the driving backplate and a surface of the light-emitting element facing away from the driving backplate.

14. The display panel according to claim 10, wherein: The surface of the first flat layer facing away from the driving backplane is flush with the surface of the light-emitting element facing away from the driving backplane. The encapsulation layer also extends to cover the first planar layer, A surface of the first planar layer facing away from the driving backplane and a surface of the light-emitting element facing away from the driving backplane are in contact with the encapsulation layer respectively.

15. The display panel according to claim 10, wherein: A surface of the first flat layer facing away from the driving back plate is flush with a surface of the protective layer covering the top surface of the quantum dot material layer facing away from the driving back plate; The display panel further includes a third flat layer located on a side of the first flat layer and the protective layer away from the driving backplane, and located on a side of the color conversion layer close to the driving backplane; The orthographic projection of the third flat layer on the driving backplane covers the driving backplane; The distance between any point on the surface of the third flat layer on the side facing away from the driving back plate and the driving back plate is equal.

16. The display panel according to any one of claims 10 to 15, characterized in that: The color conversion layer includes a black matrix and a plurality of second sub-sections, The black matrix and the plurality of second sub-sections are in the same layer; The plurality of second sub-sections are arranged in an array, and the black matrix is located between any adjacent second sub-sections and on the periphery of the array of the second sub-sections; The plurality of second sub-portions correspond one-to-one to the plurality of light-emitting elements, and the orthographic projections of the second sub-portions on the driving backplane cover the orthographic projections of the light-emitting elements on the driving backplane.

17. The display panel according to claim 16, wherein: The second sub-section includes a first color resist or a grating.

18. The display panel according to claim 17, wherein: The colors of the first color resist include red, green and blue, Along the row direction or column direction of the array of the light-emitting elements, the colors of the first color resists corresponding to any three adjacent light-emitting elements are different; The period of the grating includes a first period, a second period and a third period; The range of the first cycle is 430-470; the range of the second cycle is 400-430; the range of the third cycle is 360-390; Along the row direction or column direction of the array of the light emitting elements, the periods of the gratings corresponding to any three adjacent light emitting elements are different.

19. The display panel according to claim 16, wherein: It also includes a light extraction layer located on a side of the color conversion layer away from the driving backplane; The light extraction layer includes a plurality of third sub-portions, and the plurality of third sub-portions are arranged in an array. The plurality of third sub-portions correspond one-to-one to the plurality of second sub-portions, and the orthographic projections of the third sub-portions on the driving backplane cover the orthographic projections of the second sub-portions on the driving backplane.

20. The display panel according to claim 16, wherein The second subsection includes a grating, The display panel further includes a plurality of second color resists located on a side of the color conversion layer away from the driving backplane, and the plurality of second color resists are arranged in an array; The plurality of second color resists correspond to the plurality of second sub-portions one by one, and the orthographic projection of the second color resist on the driving backplane covers the orthographic projection of the second sub-portion on the driving backplane; The color of the second color resist is the same as the light output color of the corresponding second sub-section.

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