A display panel and a display device

Abstract

The embodiments of the present application provide a display panel and a display device, wherein the display panel includes a substrate, a display layer, and a filter layer; the display layer includes a pixel definition layer and a plurality of light-emitting devices, the pixel definition layer includes a plurality of openings; the filter layer is located on the side of the display layer away from the substrate, the filter layer includes a plurality of color filter units corresponding one to one with the light-emitting devices, at least part of the color filter units are located within the openings; wherein the surface of the color filter unit on the side away from the substrate is a curved structure. The color filter unit in the present application can effectively prevent the light emitted by the corresponding light-emitting device from being emitted from the adjacent color filter unit, thereby avoiding the occurrence of optical crosstalk. Moreover, there is no need to set up microlenses in the display panel, which simplifies the process flow and reduces the difficulty of the process. At the same time, the risk of the color filter unit and the microlens affecting each other during preparation and the risk of repeated exposure of the color filter unit and the microlens during preparation negatively affecting the light-emitting device is avoided.

Description

Technical Field

[0001] The present invention belongs to the field of display technology, and more particularly relates to a display panel and a display device. Background Art

[0002] Micro organic light-emitting diodes (Micro-OLEDs), with their excellent properties such as self-luminescence, thinness, and light weight, are a very promising solution in the field of micro-displays and have become a research focus in the display panel industry.

[0003] In existing technology, due to the high pixel density, it is difficult to achieve patterning design using high-precision metal masks for Micro-OLEDs. The more mature structure of Micro-OLED display panels includes: a patterned anode produced using a yellow light process to define sub-pixels; an unpatterned white organic light-emitting diode (WOLED) evaporated using a metal mask; a color resist layer; and a microlens array.

[0004] Among them, the white light emitted by WOLED is transmitted through the yellow light patterned color resist layer to realize the emission of light of different colors, and the emitted light passes through the microlens array to modify the light shape.

[0005] Due to the extremely small size of the sub-pixels in Micro-OLED display panels, light emitted from the WOLED light-emitting area can easily pass through adjacent color resists or microlenses, causing optical crosstalk. Furthermore, the light-emitting area, color resist, and microlens of each sub-pixel require precise multi-step alignment, making the process more difficult. Summary of the Invention

[0006] In view of this, the present application provides a display panel and a display device to solve the above problems.

[0007] In a first aspect, an embodiment of the present application provides a display panel comprising a substrate, a display layer and a filter layer; the display layer is located on one side of the substrate, and the display layer comprises a pixel definition layer and a plurality of light-emitting devices, the pixel definition layer comprising a plurality of openings; the filter layer is located on a side of the display layer away from the substrate, the filter layer comprises a plurality of color filter units, at least part of the color filter units are located in the openings, and the color filter units are arranged in a one-to-one correspondence with the light-emitting devices; and along the thickness direction of the display panel, the light-emitting devices overlap with the corresponding color filter units; wherein the color filter units comprise a first surface away from the side of the substrate and a second surface close to the substrate; the first surface is a curved surface structure protruding away from the substrate, or the first surface is a curved surface structure protruding toward the substrate.

[0008] In an implementation of the first aspect, in the portion where the color filter unit overlaps with the corresponding light-emitting device, the distance between any point on the first surface and the second surface is L, and L>0.3 / a λ ; where λ is the wavelength corresponding to the maximum intensity in the absorption spectrum of the color filter unit in the visible light range, a λ is the absorption coefficient of the color filter unit to visible light with a wavelength of λ.

[0009] In an implementation of the first aspect, the display panel further includes a first inorganic layer, which is located on a side of the filter layer close to the display layer. The thickness of the first inorganic layer is d1; wherein 20 nm ≤ d1 ≤ 500 nm.

[0010] In an implementation of the first aspect, the display panel further includes a second inorganic layer, and the first surface is a curved structure convex toward the substrate, and the second inorganic layer is conformally deposited on the plurality of color filter units.

[0011] In one implementation of the first aspect, the display panel further includes a planarization layer located on a side of the filter layer away from the display layer, the first surface is a curved structure protruding toward the substrate, the surface of the planarization layer away from the color filter unit is a planar structure, and the refractive index of the planarization layer is greater than the refractive index of the filter layer.

[0012] In an implementation of the first aspect, a portion of the first inorganic layer located at the opening of the pixel definition layer is a groove structure protruding toward the substrate; and at least a portion of the color filter unit is located in the groove structure of the first inorganic layer.

[0013] In an implementation manner of the first aspect, the thickness of the pixel definition layer is D; wherein, 0.2 μm≤D≤5 μm.

[0014] In an implementation manner of the first aspect, the color of the pixel definition layer is black.

[0015] In an implementation manner of the first aspect, a sidewall of the opening or a sidewall of the groove structure includes a reflective structure.

[0016] In an implementation of the first aspect, adjacent color filter units filter different colors, and adjacent color filter units overlap.

[0017] In an implementation of the first aspect, a light-shielding structure is included between adjacent color filter units, and the light-shielding structure is disposed on a side of the first inorganic layer away from the substrate.

[0018] In an implementation of the first aspect, there is no gap between adjacent color filter units.

[0019] In a second aspect, an embodiment of the present application provides a display device, comprising the display panel provided in the first aspect.

[0020] The display panel and display device provided in this application have the following beneficial effects:

[0021] The color filter unit is a lens structure. When the high-angle light emitted by the corresponding light-emitting device enters the color filter unit, it can be converted by the lens structure of the color filter unit into a small-angle light for output. This effectively prevents the light emitted by the light-emitting device from emitting from the adjacent color filter unit. Moreover, due to the small thickness of the first inorganic layer, the optical distance between the color filter unit and the display layer is minimized, thereby avoiding the occurrence of optical crosstalk. No additional microlenses are required in the display panel, eliminating the multiple alignment processes required for the sequential preparation of the color filter unit and the microlens, reducing the process difficulty, and avoiding the risk of mutual influence between the color filter unit and the microlens during preparation. It also effectively reduces the negative impact of repeated exposure of the color filter unit and the microlens during the preparation process on the light-emitting device. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic structural diagram of a display panel provided in an embodiment of the present application;

[0023] Figure 2 A schematic structural diagram of another display panel provided in an embodiment of the present application;

[0024] Figure 3 A schematic structural diagram of another display panel provided in an embodiment of the present application;

[0025] Figure 4 A schematic structural diagram of another display panel provided in an embodiment of the present application;

[0026] Figure 5 A schematic structural diagram of another display panel provided in an embodiment of the present application;

[0027] Figure 6 A schematic structural diagram of another display panel provided in an embodiment of the present application;

[0028] Figure 7 A schematic structural diagram of another display panel provided in an embodiment of the present application;

[0029] Figure 8 A schematic structural diagram of another display panel provided in an embodiment of the present application;

[0030] Figure 9 A schematic structural diagram of another display panel provided in an embodiment of the present application;

[0031] Figure 10A schematic structural diagram of another display panel provided in an embodiment of the present application;

[0032] Figure 11 A schematic structural diagram of another display panel provided in an embodiment of the present application;

[0033] Figure 12 A method for preparing a color filter unit provided in an embodiment of the present application;

[0034] Figure 13 A method for preparing another color filter unit provided in an embodiment of the present application;

[0035] Figure 14 A method for preparing another color filter unit provided in an embodiment of the present application;

[0036] Figure 15 A schematic diagram of a display device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0037] The terms used in the implementation section of this application are only used to explain the specific embodiments of this application and are not intended to limit this application.

[0038] Figure 1 A schematic structural diagram of a display panel provided in an embodiment of the present application is shown in FIG. Figure 2 A schematic structural diagram of another display panel provided in an embodiment of the present application.

[0039] like Figure 1 and Figure 2 As shown, an embodiment of the present application provides a display panel 001, comprising a substrate 01, a display layer 02, and a filter layer 03. In one embodiment, substrate 01 comprises a plurality of thin-film transistors, i.e., display panel 001 includes a drive circuit composed of thin-film transistors. In another embodiment, substrate 01 is a silicon-based drive substrate, i.e., display panel 001 includes a CMOS drive structure.

[0040] The display layer 02 is located on one side of the substrate 01 and includes a plurality of light-emitting devices 21 and a pixel definition layer 22. The light-emitting devices 21 are any one of organic light-emitting diodes, inorganic light-emitting diodes, quantum dot light-emitting diodes, and perovskite light-emitting diodes; and the pixel definition layer 22 includes a plurality of openings 221.

[0041] The filter layer 03 is located on the side of the display layer 02 away from the substrate 01, that is, the filter layer 03 is farther from the substrate 01 than the display layer 02. The filter layer 03 includes a plurality of color filter units 31, at least part of which is located within the opening 221. The color filter units 31 are arranged in a one-to-one correspondence with the light-emitting devices 21, and along the thickness direction of the display panel 001, the light-emitting devices 21 overlap with the corresponding color filter units 31.

[0042] The color filter unit 31 includes a first surface 31A away from the substrate 01 and a second surface 31B close to the substrate.

[0043] In one implementation of the embodiment of the present application, Figure 1 As shown, the first surface 31A is a curved structure that is convex toward the back of the substrate 01 .

[0044] In another implementation of the embodiment of the present application, Figure 2 As shown, the first surface 31A is a curved structure convex toward the substrate 01 .

[0045] In the embodiment of the present application, the light emitting device 21 can emit white light, and a color filter unit 31 is provided in the light emitting direction of the light emitting device 21 to realize color display of the display panel 001.

[0046] Optionally, the plurality of color filter units 31 may be filter units of different colors. The color filter units 31 include at least a red filter unit, a blue filter unit, and a green filter unit. In some embodiments, the filter layer 03 further includes a white filter unit.

[0047] Optionally, the multiple color filter units 31 may also be filter units of the same color.

[0048] In the embodiment of the present application, the first surface 31A of the color filter unit 31 is a curved structure. Thus, the first surface 31A of the color filter unit 31 has the effect of collimating light. The color filter unit 31 not only filters the light emitted by the light-emitting device 21, but also, the different morphologies of the first surface 31A enable the color filter unit 31 to perform a light pattern shaping function similar to a convex lens. In other words, the color filter unit 31 has a lens structure.

[0049] Furthermore, the lens structures of the multiple color filter units 31 can be one or more types depending on the material type or absorption spectrum of the color filter units 31. In particular, when the lens structures of the multiple color filter units 31 are multiple types, the multiple color filter units 31 can be arranged in a one-dimensional or two-dimensional periodic pattern in the display panel 001.

[0050] It is understood that the lens structure has the function of collimating the light path and improving the display brightness. In addition, adjusting the lens structure can also change the pixel's center angle of illumination, compensating for brightness and color difference at the edge of the screen under wide viewing angles.

[0051] In the embodiment of the present application, the color filter unit 31 is a lens structure. When the large-angle light emitted by the corresponding light-emitting device 21 is incident on the color filter unit 31, it can be converted by the lens structure of the color filter unit 31 into a small-angle light for emission. Therefore, it can effectively prevent the light emitted by the light-emitting device 21 from being emitted from the adjacent color filter unit 31, thereby avoiding the occurrence of optical crosstalk. In addition, no additional microlenses are required in the display panel 001, which saves the multiple alignment processes required for the color filter unit 31 and the microlens to be prepared in sequence, reduces the process difficulty and saves costs. The risk of mutual influence between the color filter unit 31 and the microlens during preparation is avoided. In addition, the negative impact of repeated exposure of the color filter unit 31 and the microlens during the preparation process on the light-emitting device 21 is effectively reduced.

[0052] In order to ensure the filtering effect of the color filter unit 31, the present application has made a specific design on the geometric parameters of the color filter unit 31. Figure 1 As shown, in one embodiment of the present application, in the portion where the color filter unit 31 overlaps with the corresponding light emitting device 21, the distance between any point on the first surface 31A and the second surface 31B is L, and L>0.3 / a λ Wherein, λ is the wavelength corresponding to the maximum intensity in the absorption spectrum of the color filter unit 31 in the visible light range, a λ is the absorption coefficient of the color filter unit 31 for visible light with a wavelength of λ, in cm -1 .

[0053] It should be noted that the wavelength in the visible light range can be 450nm to 680nm. According to Lambert-Beer law, lg(1 / T)=b*a λ , where T is the transmittance, that is, the ratio of the transmitted light intensity to the incident light intensity; b is the thickness of the absorption layer, in cm. When T is 50%, that is, when the incident light intensity is absorbed by 50%, b = lg2 / a λ , that is, b≈0.3 / a λ .

[0054] In the embodiment of the present application, the distance between any point on the first surface 31A and the second surface 31B is greater than 0.3 / a λ , that is, the thickness of any part of the color filter unit 31 for absorbing light is greater than 0.3 / a λ This ensures that the color filter unit 31 absorbs at least 50% of the incident stray light, thereby satisfying the filtering effect of the color filter unit 31 .

[0055] In one embodiment of this application, please continue to refer to Figure 1 and Figure 2 The display panel 001 further includes a first inorganic layer 04, which is located on a side of the filter layer 03 close to the display layer 02. The thickness of the first inorganic layer 04 is d1, where 20 nm ≤ d1 ≤ 500 nm.

[0056] The first inorganic layer 04 can be a highly conformal inorganic layer produced using an atomic layer deposition process. Produced using the atomic layer deposition process, the first inorganic layer 04 can be made thinner. Furthermore, compared to inorganic layers produced using chemical vapor deposition, the first inorganic layer 04 is more compact. In other words, compared to inorganic layers produced using chemical vapor deposition, the first inorganic layer 04 has a stronger water and oxygen barrier capability. Furthermore, the first inorganic layer 04 has the ability to encapsulate particles, enabling it to encapsulate and secure impurities that land on the display panel being manufactured. When the filter layer 03 is produced using a wet process on top of the first inorganic layer 04, the first inorganic layer 04 effectively blocks water, oxygen, and solvents used in the process, preventing damage to the underlying light-emitting device 21.

[0057] In the embodiment of the present application, the first inorganic layer 04 has extremely strong conformality and water and oxygen barrier capabilities. Conformality means that the first inorganic layer 04 can completely cover the underlying substrate with uneven topography, forming a continuous film layer on the uneven topography.

[0058] In one implementation of this embodiment, each color filter unit 31 contacts the same surface of the first inorganic layer 04. Here, the same surface refers to a single, continuous surface, i.e., a whole, uninterrupted surface. Furthermore, each color filter unit 31 contacts the surface of the first inorganic layer 04 facing away from the substrate 01. In other words, each color filter unit 31 is formed on the same base layer, which is the first inorganic layer 04. In other words, each color filter unit 31 is located at a substantially equal vertical distance from the substrate 01.

[0059] In the present application, the first inorganic layer 04 has a relatively small thickness, which can reduce the optical spacing between the color filter unit 31 and the display layer 02. When the vertical spacing between the light-emitting device 21 and the color filter unit 31 decreases, the proportion of light emitted by the light-emitting device 21 that passes through the corresponding color filter unit 31 increases, effectively reducing the proportion of light emitted by the light-emitting device 21 that passes through the adjacent color filter unit 31, thereby further reducing the occurrence of optical crosstalk.

[0060] Figure 3 A schematic structural diagram of another display panel provided in an embodiment of the present application.

[0061] In one embodiment of the present application, Figure 3 As shown, the first inorganic layer 04 includes an inorganic stacking pair 50. An inorganic stacking pair 50 includes a first sub-inorganic layer 51 and a second sub-inorganic layer 52. In some embodiments, the first inorganic layer 04 includes two or more inorganic stacking pairs 50, and in each inorganic stacking pair 50, the first sub-inorganic layer 51 is located on the side of the second sub-inorganic layer 52 closer to the display layer 02.

[0062] In some embodiments, the material of the first sub-inorganic layer 51 is any one of zirconium oxide (ZrO2), silicon nitride (Si3N4), silicon oxide (SiO2), aluminum oxide (Al2O3) or a mixture of several of them, and the second sub-inorganic layer 52 is any one of ZrO2, SiO2, Si3N4, aluminoxane (Alucone), titanium oxide (TiO2) or a mixture of several of them, wherein the materials of the first sub-inorganic layer 51 and the second sub-inorganic layer 52 are different.

[0063] In some embodiments, the material of the first inorganic sub-layer 51 is Al2O3, and the material of the second inorganic sub-layer 52 is TiO2. The inorganic stack 50 is an Al2O3 layer / TiO2 layer. The Al2O3 layer, produced using atomic layer deposition, has a high density and can effectively block water and oxygen. However, when the filter layer 03 is produced using a wet process (such as spin coating), the water-based solution used in the process has a certain corrosive effect on the Al2O3 layer. After the TiO2 layer is formed on top of the Al2O3 layer, the TiO2 layer can protect the Al2O3 layer during the wet process. This allows the filter layer 03 to be produced after the first inorganic layer 04 is produced, placing the filter layer 03 above the first inorganic layer 04 while ensuring the structural integrity of the first inorganic layer 04. The first inorganic layer 04 can effectively protect the light-emitting device 21 during the production of the filter layer 03.

[0064] In one embodiment, the material of the first inorganic sub-layer 51 is Al2O3, and the material of the second inorganic sub-layer 52 is Alucone. The inorganic stacked layer pair 50 is an Al2O3 layer / Alucone layer.

[0065] Figure 4 A schematic structural diagram of another display panel provided in an embodiment of the present application.

[0066] In one embodiment of the present application, Figure 4As shown, the display panel 001 further includes a second inorganic layer 05. When the first surface 31A is a curved structure that is convex facing away from the substrate 01, the second inorganic layer 05 is conformally deposited on the multiple color filter units 31. The second inorganic layer 05 protects the color filter units 31 and the light-emitting devices 21 from corrosion by water and oxygen. Furthermore, the shape of the second inorganic layer 05 is similar to that of the first surface 31A, further shaping the light pattern exiting the color filter units 31 to prevent optical crosstalk. The second inorganic layer 05 can be a conformal inorganic layer fabricated using an atomic layer deposition process or a chemical vapor deposition process.

[0067] Figure 5 A schematic structural diagram of another display panel provided in an embodiment of the present application.

[0068] In one embodiment of the present application, Figure 5 As shown, the display panel 001 further includes a planarization layer 06, which is located on the side of the filter layer 03 away from the display layer 02. When the first surface 31A is a curved structure convex toward the substrate 01, the surface of the planarization layer 06 away from the color filter unit 31 is a flat structure, and the refractive index of the planarization layer 06 is greater than the refractive index of the filter layer 03.

[0069] It should be noted that the planarization layer 06 may be made of a resin material containing metal oxide particles. The resin material doped with metal oxide can increase the refractive index of the planarization layer 06. Optionally, the metal oxide is zirconium oxide or titanium oxide.

[0070] It will be appreciated that in the embodiment of the present application, the surface of the planarization layer 06 near the color filter unit 31 is a curved structure. The law of refraction states that, given a constant angle of incidence, the greater the refractive index, the smaller the refraction angle. Therefore, while the planarization layer 06 provides water and oxygen protection for the color filter unit 31, it can also further shape the light pattern exiting the color filter unit 31, preventing optical crosstalk.

[0071] It should be noted that the second inorganic layer 05 may be further prepared on the side of the planarization layer 06 away from the filter layer 03 .

[0072] Figure 6 A schematic structural diagram of another display panel provided in an embodiment of the present application; Figure 7 A schematic structural diagram of another display panel provided in an embodiment of the present application.

[0073] In one embodiment of the present application, Figure 6 and Figure 7As shown, the pixel definition layer 22 is used to space and define adjacent sub-pixels, and the height of the light-emitting film layer in the pixel definition layer 22 is lower than the height of the opening 221. In an embodiment of the present application, the display layer 02 also includes a graphically designed bottom electrode 23, a top electrode 24 arranged on the entire surface, and a light-emitting material layer 25. Among them, the bottom electrode 23 is closer to the substrate 01 than the top electrode 24. Along the thickness direction of the display panel 001, the light-emitting material layer 25 covers the bottom of the opening 221 and at least part of the side wall of the opening 221. The portion where the light-emitting material layer 25 overlaps with the bottom electrode 23 and the top electrode 24 can be a light-emitting device 21. Furthermore, the light-emitting material layer 25 can also include at least one of an electron transport layer, an electron injection layer, a hole transport layer, a hole injection layer, and sub-layers such as an organic light-emitting layer, which are not shown in the figure.

[0074] Optionally, the luminescent material layer 25 is continuously provided on the entire surface. When a metal mask is used to evaporate the luminescent material, it is convenient to operate and reduce the difficulty of the process.

[0075] In one embodiment of the present application, Figure 7 As shown, the light-emitting material layer 25 further includes a first sublayer 251, which is interrupted at the corresponding sidewalls of the opening 221. In other words, the first sublayer 251 is provided discontinuously. Optionally, the first sublayer 251 is a hole transport layer. When the light-emitting device 21 emits light, this prevents charge from migrating to adjacent areas, thereby preventing the appearance of light spots in adjacent areas where light is not desired. This, in turn, prevents the normal light emission of the display panel 001 from being affected.

[0076] The first inorganic layer 04 is conformally deposited on the side of the pixel definition layer 22 facing away from the substrate 01. The portion of the first inorganic layer 04 located at the opening 221 forms a groove structure 41 protruding toward the substrate 01. In other words, the opening 221 in the display layer 02 forms a groove structure 41 protruding toward the substrate 01, and the portion of the first inorganic layer 04 located at the opening 221 forms a groove structure 41. Each groove structure 41 corresponds to one color filter unit 31; at least a portion of the color filter unit 31 is located within the groove structure 41.

[0077] Please continue to refer to Figure 6 In one embodiment of the present application, the thickness of the pixel definition layer 22 is D, wherein 0.2 μm≤D≤5 μm.

[0078] In the embodiment of the present application, the pixel definition layer 22 is set to be thicker, so the height of the opening 221 can be larger, thereby ensuring a larger height of the groove structure 41 in the first inorganic layer 04. Because the color filter unit 31 is disposed in the groove structure 41, when the light-emitting device 21 emits light, the vast majority of the light will be emitted through the corresponding color filter unit 31, thereby minimizing the occurrence of optical crosstalk.

[0079] The light emitted by the light emitting device 21 has a certain angle, and part of the light with a large angle will be emitted along the side wall of the opening 221. In the embodiment of the present application, the color filter unit 31 is set in the groove structure 41 formed by the first inorganic layer 04, such as Figure 6 At the center region AA, only the light-emitting material layer 25, the top electrode 24, and the first inorganic layer 04 separate the sidewalls of the opening 221 from the color filter unit 31, resulting in a relatively small distance between the sidewalls of the opening 221 and the color filter unit 31. When the first inorganic layer 04 is fabricated using an atomic layer deposition process, its thickness can range from 20 nm to 500 nm. In some embodiments, the thickness of the first inorganic layer 04 is approximately 200 nm. This ensures that the distance between the sidewalls of the opening 221 and the color filter unit 31 is less than the wavelength of visible light. Consequently, light emitted by the light-emitting device 21 is unlikely to bypass the color filter unit 31. In other words, the vast majority of light emitted by the light-emitting device 21 is emitted through the corresponding color filter unit 31, minimizing optical crosstalk.

[0080] In the embodiment of the present application, the thickness of the pixel definition layer 22 is relatively thick, which enables the first inorganic layer 04 to form a groove structure 41 to accommodate the color filter unit 31 after the first inorganic layer 04 process, thereby achieving a smaller distance between the side wall of the opening 221 of the pixel definition layer 22 and the color filter unit 31, so that the large-angle light emitted along the side wall of the opening 221 of the pixel definition layer 22 can also enter the corresponding color filter unit 31, further improving the optical crosstalk problem.

[0081] In one embodiment of the present application, the color of the pixel definition layer 22 is black, that is, the material of the pixel definition layer 22 includes a black light-absorbing material.

[0082] In the embodiment of the present application, black has a strong absorption property for light, which can prevent light from being emitted from the solid part of the pixel definition layer 22. As a result, most of the light emitted by the light-emitting device 21 is emitted through the corresponding color filter unit 31, thereby minimizing the occurrence of optical crosstalk.

[0083] Figure 8 A schematic structural diagram of another display panel provided in an embodiment of the present application.

[0084] In one embodiment of the present application, Figure 8 As shown, the sidewall of the opening 221 or the sidewall of the groove structure 41 includes a reflective structure M.

[0085] In the embodiment of the present application, the reflective structure M covering the sidewall of the opening 221 can reflect the large-angle light emitted by the light-emitting device 21, thereby preventing the large-angle light from being emitted to the adjacent color filter unit 31 and causing optical crosstalk.

[0086] Figure 9 This is a structural diagram of another display panel provided in an embodiment of the present application. Figure 10 This is a structural diagram of another display panel provided in an embodiment of the present application. Figure 11 A schematic structural diagram of another display panel provided in an embodiment of the present application.

[0087] In one embodiment of the present application, Figure 9 and Figure 10 As shown, there are no gaps between adjacent color filter units 31. It should be noted that the filter colors of adjacent color filter units 31 can be different. This arrangement can increase the area of a single color filter unit 31 to a certain extent. As a result, some high-angle light emitted along the sidewalls of the opening 221 can also enter the corresponding color filter unit 31 after passing through the first inorganic layer 04. This can further reduce the optical ratio of high-angle light entering adjacent color filter units 31, thereby improving optical crosstalk.

[0088] In one implementation of the embodiment of the present application, adjacent color filter units 31 have different filtering colors, and adjacent color filter units 31 overlap.

[0089] For example, please refer to Figure 9 The two adjacent color filter units 31 include a first color filter unit 31C and a second color filter unit 31D; the first color filter unit 31C and the second color filter unit 31D have different filtering colors, and the first color filter unit 31C and the second color filter unit 31D overlap.

[0090] In another implementation of the embodiment of the present application, Figure 10 As shown, adjacent color filter units 31 are closely arranged, and along the thickness direction of the display panel 001 , adjacent color filter units 31 do not overlap.

[0091] It is understood that the light emitted by the light-emitting device 21 may be emitted from the edge of the corresponding color filter unit 31. In the embodiment of the present application, since there is no gap between adjacent color filter units 31, the light emitted from the edge of the color filter unit 31 will be incident on the adjacent color filter unit 31. Since the adjacent color filter units 31 filter different colors, the light incident on the adjacent color filter unit 31 will be filtered out, thereby minimizing the occurrence of optical crosstalk.

[0092] For example, please refer to Figure 9 and Figure 10 The light-emitting device 21 corresponds to the first color filter unit 31C, which only allows red light to pass through. The second color filter unit 31D, adjacent to the first color filter unit 31C, only allows green light to pass through. When light emitted by the light-emitting device 21 exits from the edge of the first color filter unit 31C near the second color filter unit 31D, it is understood that the emitted light is red. Since there is no gap between the first color filter unit 31C and the second color filter unit 31D, the red light emitted from the edge of the first color filter unit 31C near the second color filter unit 31D enters the second color filter unit 31D. Furthermore, since the second color filter unit 31D only allows green light to pass through, the red light is filtered out by the second color filter unit 31D. This ensures that the light emitted from the first color filter unit 31C does not overlap with the light emitted from the second color filter unit 31D, thereby minimizing the occurrence of optical crosstalk.

[0093] In one embodiment of the present application, Figure 11 As shown, a light shielding structure N is included between adjacent color filter units 31 , and the light shielding structure N is arranged on a side of the first inorganic layer 04 away from the substrate 01 .

[0094] It is understood that the light shielding structure N can prevent light from passing through. In the embodiment of the present application, since the light shielding structure N is provided between adjacent color filter units 31, light emitted from the edge of the color filter unit 31 is blocked by the light shielding structure M, preventing the light from entering the upper part of the adjacent color filter unit 31. This minimizes the occurrence of optical crosstalk.

[0095] Figure 12 A method for preparing a color filter unit is provided in an embodiment of the present application.

[0096] like Figure 12 As shown, the embodiment of the present application provides a method for preparing a color filter unit 31 using a gradient transmittance mask P1, and the specific steps are as follows:

[0097] S1: The precursor fluid of the color filter unit 31 is applied to the first inorganic layer 04 to form a thin film. Coating methods include, but are not limited to, spin coating, doctor blade coating, inkjet printing, and electrofluidic printing. The precursor fluid of the color filter unit 31 contains a dye and a UV positive photoresist (i.e., a photoresist in which the degree of crosslinking of the polymer components is reduced to a certain extent after exposure to UV light). The UV positive photoresist may include the following components: a binder, a crosslinking component, a photoinitiator, a solvent, etc. The types of binders include, but are not limited to, polymers such as polyurethanes, epoxy resins, phenolic resins, polyacrylates, and silicones, and their corresponding monomers and oligomers. The types of crosslinking components include, but are not limited to, polyester resin (PET), pentaerythritol triacrylate (PETA), dipentaerythritol hexaacrylate (DPHA), etc. After exposure to UV light, the photoinitiator's products inhibit the bonding process between the binder and the crosslinking component. It should be noted that step S1 may include post-coating standing for leveling and pre-baking.

[0098] S2: Expose the color filter unit 31 precursor film using a gradient transmittance (halftone) mask P1. The mask has several light-blocking portions that correspond one-to-one to a number of light-emitting devices 21 during exposure. The exposure light source is ultraviolet light, such as light with a central wavelength of approximately 365 nm. The transmittance of the light-blocking portions to the exposure light source is gradually distributed on a plane parallel to the plane of the substrate 01. Due to the absorption of the exposure light by the positive photoresist component in the color filter unit 31 precursor, at the exposed position, the side of the color filter unit 31 precursor film away from the light source receives less exposure intensity than the side closer to the light source. This causes the low exposure intensity area to be concentrated at the bottom of the color filter unit 31 precursor film (close to the first inorganic layer 04), forming a definable curved surface on the upper portion of the color filter unit 31 precursor.

[0099] S3: Immerse and develop in a developer capable of dissolving the low-crosslinked positive photoresist. The low-exposure intensity areas from step S2 will remain on the surface of the first inorganic layer 04, forming color filter elements 31. Step S3 may also include post-development cleaning and post-baking (using a higher temperature to further solidify the photoresist and evaporate the solvent).

[0100] S4: In the surface area of the first inorganic layer 04 corresponding to the light-emitting device 21 without the corresponding color filter unit 31, repeat steps S1 to S3 using a color filter unit 31 precursor of the same type or containing other types of dyes to obtain other color filter units 31 of the same filtering color or color filter units 31 of different filtering colors.

[0101] The preparation method provided in the examples of this application can obtain Figure 1The color filter unit 31 is shown. The first surface 31A of the color filter unit 31 is a curved surface structure that is convex toward the substrate 01 .

[0102] Figure 13 Another method for preparing a color filter unit is provided in an embodiment of the present application.

[0103] like Figure 13 As shown, the embodiment of the present application provides a method for preparing the color filter unit 31 using a post-photolithography hot melt reflow process, and the specific steps are as follows:

[0104] S1: The precursor fluid of the color filter unit 31 is applied to the first inorganic layer 04 to form a thin film. Coating methods include, but are not limited to, spin coating, doctor blade coating, inkjet printing, and electrofluidic printing. The precursor fluid of the color filter unit 31 contains a dye and a UV negative photoresist (i.e., a photoresist whose polymer components undergo a certain degree of cross-linking after exposure to UV light). Alternatively, the precursor fluid of the color filter unit 31 contains a dye and a UV positive photoresist (i.e., a photoresist whose polymer components undergo a certain degree of cross-linking after exposure to UV light). Both UV negative and UV positive photoresists may contain the following components: a binder, a cross-linking component, a photoinitiator, a solvent, etc. The types of binders include, but are not limited to, polymers such as polyurethanes, epoxy resins, phenolic resins, polyacrylates, and silicones, and their corresponding monomers and oligomers. The types of cross-linking components include, but are not limited to, polyester resin (PET), pentaerythritol triacrylate (PETA), dipentaerythritol hexaacrylate (DPHA), etc. After the photoinitiator is irradiated by ultraviolet light, its product will promote the bonding process between the adhesive and the cross-linking component. Step S1 may also include standing and leveling after coating and pre-baking.

[0105] S2: The color filter unit 31 precursor film is patterned using photolithography, leaving separate portions of the color filter unit 31 on the first inorganic layer 04 that correspond one-to-one with the plurality of light-emitting devices 21. The photolithography steps may include exposure, development, rinsing, and post-baking. The exposure step can be performed using a collimated ultraviolet light source and a mask containing a plurality of openings or shielding portions. The openings or shielding portions of the mask correspond one-to-one with the plurality of light-emitting devices 21 (not shown).

[0106] S3: Repeat steps S1 to S2 on the surface area of the first inorganic layer 04 of the light-emitting device 21 without the corresponding color filter unit 31 using a color filter unit 31 precursor of the same type or containing other types of dyes.

[0107] S4: The separated color filter units 31 are heated to a temperature 20°C above their glass transition temperature to melt until their surfaces reflow due to tension to form an upwardly protruding curved surface. That is, the center of the curved surface is farther from the bottom of the color filter unit 31 than the edge. The temperature is then cooled to room temperature.

[0108] The preparation method provided in the examples of this application can obtain Figure 1 The color filter unit 31 is shown. The first surface 31A of the color filter unit 31 is a curved surface structure that is convex toward the substrate 01 .

[0109] The preparation method provided in the embodiment of the present application does not need to limit the positive and negative properties of the photoresist, and does not require the use of unconventional processes during the exposure process. It has the advantages of strong operability and a wide range of applications.

[0110] Figure 14 Another method for preparing a color filter unit is provided in an embodiment of the present application.

[0111] like Figure 14 As shown, the embodiment of the present application provides a method for preparing the color filter unit 31 using a post-lithography shrinking process, and the specific steps are as follows:

[0112] S1: The precursor fluid of the color filter unit 31 is applied to the first inorganic layer 04 to form a thin film. Coating methods include, but are not limited to, spin coating, doctor blade coating, inkjet printing, and electrofluidic printing. The precursor fluid of the color filter unit 31 contains a dye and a UV negative photoresist (i.e., a photoresist whose polymer components undergo a certain degree of cross-linking after exposure to UV light). Alternatively, the precursor fluid of the color filter unit 31 contains a dye and a UV positive photoresist (i.e., a photoresist whose polymer components undergo a certain degree of cross-linking after exposure to UV light). Both UV negative and UV positive photoresists may contain the following components: a binder, a cross-linking component, a photoinitiator, a solvent, etc. The types of binders include, but are not limited to, polymers such as polyurethanes, epoxy resins, phenolic resins, polyacrylates, and silicones, and their corresponding monomers and oligomers. The types of cross-linking components include, but are not limited to, polyester resin (PET), pentaerythritol triacrylate (PETA), dipentaerythritol hexaacrylate (DPHA), etc. After the photoinitiator is irradiated by ultraviolet light, its product will promote the bonding process between the adhesive and the cross-linking component. Step S1 may also include standing and leveling after coating and pre-baking.

[0113] It should be noted that the precursor of the color filter unit 31 may include a solvent with a higher component.

[0114] S2: The color filter unit 31 precursor film is patterned using photolithography, leaving separate portions of the color filter unit 31 on the first inorganic layer 04 that correspond one-to-one with the plurality of light-emitting devices 21. The photolithography steps may include exposure, development, and rinsing. The exposure step can be performed using a collimated ultraviolet light source and a mask having a plurality of openings or shielding portions. The openings or shielding portions of the mask correspond one-to-one with the plurality of light-emitting devices 21 (not shown).

[0115] S3: The patterned color filter unit 31 precursor is heat-treated (post-baked). As the photoresist further solidifies, the higher-component solvent evaporates, causing its volume to shrink significantly. Because the color filter unit 31 material and the first inorganic layer 04 have a strong bond, the color filter unit 31 layer is prevented from falling off the first inorganic layer 04. Furthermore, because the first inorganic layer 04 includes the groove structure 41, the upper surface of the color filter unit 31 can form a concave curved surface.

[0116] S4: In the surface area of the first inorganic layer 04 corresponding to the light-emitting device 21 without the corresponding color filter unit 31, repeat steps S1 to S3 using a color filter unit 31 precursor of the same type or containing other types of dyes to obtain other color filter units 31 of the same filtering color or color filter units 31 of different filtering colors.

[0117] The preparation method provided in the examples of this application can obtain Figure 2 The color filter unit 31 is shown. The first surface 31A of the color filter unit 31 is a curved structure convex toward the substrate 01.

[0118] It should be noted that in the preparation method of the color filter unit 31 provided in the present application, the preparation equipment used includes a film-forming device (such as a doctor blade, an inkjet printer, a vapor deposition machine, a magnetron sputtering machine, a chemical vapor deposition device), an exposure device (such as an ultraviolet exposure machine), a mask plate (such as a film template, a chrome mask plate), an etching device (such as an inductively coupled plasma etcher), and other devices.

[0119] Figure 15 A schematic diagram of a display device provided in an embodiment of the present application.

[0120] like Figure 15 As shown, the display device provided in the embodiment of the present application can be a mobile phone. In addition, the display device provided in the embodiment of the present application can also be a computer, a television, a car display, a micro projector, a camera electronic viewfinder, a head-mounted near-eye display, or other display device. The display device provided in the embodiment of the present application includes the display panel 001 provided in any of the above embodiments.

[0121] In the embodiment of the present application, the color filter unit 31 is a lens structure. When high-angle light emitted by the corresponding light-emitting device 21 is incident on the color filter unit 31, it can be converted by the lens structure of the color filter unit 31 into low-angle light for output. This effectively prevents light emitted by the light-emitting device 21 from being emitted from adjacent color filter units 31. Furthermore, due to the relatively small thickness of the first inorganic layer 04, the optical distance between the color filter unit 31 and the display layer 02 is minimized, thereby avoiding optical crosstalk. No additional microlenses are required in the display panel 001, eliminating the multiple alignment processes required for sequentially preparing the color filter unit 31 and the microlenses, reducing process complexity, and avoiding the risk of mutual interference between the color filter unit 31 and the microlenses during preparation. Furthermore, the negative impact of repeated exposure of the color filter unit 31 and the microlenses during preparation on the light-emitting device 21 is effectively reduced.

[0122] 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 principles of the present invention should be included in the scope of protection of the present invention.

[0123] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A display panel, characterized in that: The display panel includes: substrate; A display layer is located on one side of the substrate, the display layer including a pixel definition layer and a plurality of light-emitting devices; the pixel definition layer includes a plurality of openings; a filter layer located on a side of the display layer away from the substrate, the filter layer comprising a plurality of color filter units, at least portions of the color filter units being located within the openings; the color filter units being arranged in a one-to-one correspondence with the light-emitting devices, and the light-emitting devices overlapping with corresponding color filter units along a thickness direction of the display panel; a first inorganic layer located on a side of the filter layer close to the display layer, the color filter unit being in contact with a same surface of the first inorganic layer; a portion of the first inorganic layer located at the opening of the pixel definition layer being a groove structure protruding toward the substrate, and at least a portion of the color filter unit being located within the groove structure of the first inorganic layer; The color filter unit includes a first surface away from the substrate and a second surface close to the substrate; the first surface is a curved structure convex away from the substrate, or the first surface is a curved structure convex toward the substrate.

2. The display panel according to claim 1, wherein: In the overlapping portion of the color filter unit and the corresponding light emitting device, the distance between any point on the first surface and the second surface is L, and L>0.3 / a λ ; Wherein, λ is the wavelength corresponding to the maximum intensity in the absorption spectrum of the color filter unit in the visible light range, a λ is the absorption coefficient of the color filter unit to visible light with a wavelength of λ.

3. The display panel according to claim 1, wherein: The thickness of the first inorganic layer is d1, wherein 20 nm ≤ d1 ≤ 500 nm.

4. The display panel according to claim 1 or 3, wherein: The display panel further includes a second inorganic layer, and the first surface is a curved structure protruding away from the substrate, and the second inorganic layer is conformally deposited on the plurality of color filter units.

5. The display panel according to claim 1 or 3, wherein: The display panel further includes a planarization layer located on a side of the filter layer away from the display layer, and the first surface is a curved structure convex toward the substrate; A surface of the planarization layer away from the color filter unit is a planar structure, and a refractive index of the planarization layer is greater than a refractive index of the filter layer.

6. The display panel according to claim 3, wherein: The pixel definition layer has a thickness D, wherein 0.2 μm≤D≤5 μm.

7. The display panel according to claim 1, wherein: The color of the pixel definition layer is black.

8. The display panel according to claim 3, wherein: A side wall of the opening or a side wall of the groove structure includes a reflective structure.

9. The display panel according to claim 3, wherein: The adjacent color filter units have different filtering colors, and the adjacent color filter units overlap.

10. The display panel according to claim 3, wherein: A light shielding structure is provided between adjacent color filter units, and the light shielding structure is provided on a side of the first inorganic layer away from the substrate.

11. The display panel according to claim 3, wherein There is no gap between adjacent color filter units.

12. A display device, characterized in that: The display panel comprises the display panel according to any one of claims 1 to 11.

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