Display panel for improving emergent light collimation and preparation method thereof

Abstract

The invention provides a display panel for improving emergent light collimation and a preparation method thereof, and belongs to the technical field of photoelectron manufacturing. The display panel comprises a light-emitting functional layer, a driving substrate and a collimation layer, the light-emitting functional layer is located on the driving substrate and electrically connected with the driving substrate, and the light-emitting functional layer comprises a plurality of light-emitting units arranged at intervals; the collimation layer is located on the side, away from the driving substrate, of the light-emitting functional layer, the collimation layer is provided with collimation holes exposing the light-emitting functional layer, the collimation holes correspond to the light-emitting units one to one, and orthographic projections of the light-emitting units on the surface of the driving substrate are larger than those of the light-emitting units on the surface of the driving substrate. And the plurality of collimating holes are positioned in the orthographic projection of the corresponding collimating holes on the surface of the driving substrate. According to the embodiment of the invention, the problem of light crosstalk between adjacent light emitting units in the display panel can be improved, and the light emitting collimation of the display panel is improved.

Description

Technical Field

[0001] This disclosure relates to the field of optoelectronic manufacturing technology, and in particular to a display panel with improved light output collimation and a method for its fabrication. Background Technology

[0002] Micro LED (Micro Light Emitting Diode) is a display technology that miniaturizes LEDs to the micrometer level.

[0003] Micro LED (Micro Light Emitting Diode) display panels are a display technology that uses micron-sized LED chips as self-emissive pixels. It integrates millions of Micro LED chips onto a driving substrate using mass transfer technology, enabling independent light control for each pixel.

[0004] In related technologies, display panels typically include a driving substrate and multiple Micro LED chips. Multiple Micro LED chips are arranged in an array on the driving substrate, and each Micro LED chip is electrically connected to the driving substrate so that the integrated circuit on the driving substrate can control the light emission of each Micro LED chip.

[0005] However, the small size of Micro LED chips, the close spacing between Micro LED chips on the driving substrate, and the large emission angle of Micro LED chips mean that the light emitted by Micro LED chips may illuminate adjacent Micro LED chips, resulting in problems such as light crosstalk and contrast loss. Summary of the Invention

[0006] This disclosure provides a display panel with improved light emission collimation and a method for manufacturing the same, which can improve the light crosstalk problem between adjacent light-emitting units in the display panel and enhance the light emission collimation of the display panel. The technical solution is as follows:

[0007] On one hand, this disclosure provides a display panel, the display panel including: a light-emitting functional layer, a driving substrate, and a collimation layer, the light-emitting functional layer being located on the driving substrate and electrically connected to the driving substrate, the light-emitting functional layer including a plurality of spaced-apart light-emitting units; the collimation layer being located on the side of the light-emitting functional layer away from the driving substrate, and the collimation layer having collimation holes exposing the light-emitting functional layer, the collimation holes corresponding one-to-one with the light-emitting units, the orthographic projection of the light-emitting unit on the surface of the driving substrate being located within the orthographic projection of the corresponding collimation hole on the surface of the driving substrate.

[0008] In one implementation of this disclosure, the collimation layer is a conductive film layer, each of the light-emitting units is electrically connected to the collimation layer, and the collimation layer is electrically connected to the driving substrate.

[0009] In another implementation of this disclosure, the collimation layer includes a metal layer.

[0010] In another implementation of this disclosure, the display panel further includes a transparent conductive layer located on the surface of the light-emitting functional layer away from the driving substrate and electrically connected to each of the light-emitting units; the collimation layer is located on the surface of the transparent conductive layer away from the driving substrate.

[0011] In another implementation of this disclosure, the display panel further includes a light-collecting structure for focusing light, the light-collecting structure corresponding one-to-one with the collimating aperture, and the light-collecting structure being located within the corresponding collimating aperture.

[0012] In another implementation of this disclosure, the surface of the light-collecting structure away from the driving substrate is an arc surface.

[0013] In another implementation of this disclosure, the thickness of the light-collecting structure is less than or equal to the depth of the collimating aperture.

[0014] In another implementation of this disclosure, the display panel further includes an insulating reflective layer located on the driving substrate and filling the gaps between the plurality of light-emitting units, and the collimation layer located on the surface of the insulating reflective layer away from the driving substrate.

[0015] In another implementation of this disclosure, the thickness of the insulating reflective layer is greater than or equal to the thickness of the light-emitting unit.

[0016] Secondly, embodiments of this disclosure provide a method for fabricating a display panel, the method comprising: forming a light-emitting functional layer on a substrate; bonding the light-emitting functional layer to a driving substrate and removing the substrate to electrically connect the light-emitting functional layer to the driving substrate; patterning the light-emitting functional layer to form a plurality of spaced light-emitting units; forming a collimation layer on the side of the light-emitting functional layer away from the driving substrate, the collimation layer having collimation holes exposing the light-emitting functional layer, the collimation holes corresponding one-to-one with the light-emitting units, and the orthographic projection of the light-emitting unit on the surface of the driving substrate being located within the orthographic projection of the corresponding collimation hole on the surface of the driving substrate.

[0017] The beneficial effects of the technical solutions provided in this disclosure include at least the following:

[0018] The display panel provided in this embodiment of the present disclosure has a collimation layer disposed on one side of the light-emitting functional layer, such that each collimation hole on the collimation layer corresponds one-to-one with a single light-emitting unit in the light-emitting functional layer, and the orthographic projection of the light-emitting unit on the surface of the driving substrate is completely within the orthographic projection range of the corresponding collimation hole. This requires the light emitted by the light-emitting unit to pass through the collimation hole first, and the aperture and position of the collimation hole are optically designed to allow only light in the target direction to pass through, thus physically restricting the propagation path of stray light in non-target directions.

[0019] Meanwhile, the collimation layer itself acts as a barrier above the surface of the light-emitting unit, and the sidewalls of its collimation aperture form vertical or inclined shielding boundaries. When the light-emitting unit emits light, the divergent beam, which would normally easily diffuse in all directions due to the close arrangement of small-sized chips, is blocked by the aperture walls. Only light rays along the collimation aperture axis or at narrow angles can pass through smoothly, while lateral stray light towards adjacent light-emitting units is reflected or absorbed by the aperture walls. This combination of physical shielding and directional light emission directly blocks the possibility of light illuminating adjacent light-emitting units, thereby reducing optical crosstalk.

[0020] Furthermore, in related technologies, stray light between adjacent light-emitting units can superimpose onto the display area of ​​the target pixel, resulting in increased background brightness in dark states and decreased light purity of the target pixel in bright states, ultimately leading to blurred contrast in the overall image. However, the collimation layer in this embodiment precisely controls the light emission direction of each light-emitting unit, ensuring concentrated light output from the target pixel and effectively suppressing stray light from non-target areas. This results in brighter bright states and darker dark states, effectively improving contrast. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this disclosure, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of a display panel provided in an embodiment of this disclosure;

[0023] Figure 2 This is a partial structural schematic diagram of a display panel provided in an embodiment of this disclosure;

[0024] Figure 3 This is a flowchart of a method for manufacturing a display panel according to an embodiment of this disclosure;

[0025] Figure 4 This is a manufacturing state diagram of a display panel provided in an embodiment of this disclosure;

[0026] Figure 5 This is a manufacturing state diagram of a display panel provided in an embodiment of this disclosure;

[0027] Figure 6 This is a manufacturing state diagram of a display panel provided in an embodiment of this disclosure.

[0028] The markings in the diagram are explained as follows:

[0029] 10. Light-emitting functional layer; 100. Light-emitting unit;

[0030] 11. First semiconductor layer; 12. Multiple quantum well layer; 13. Second semiconductor layer;

[0031] 20. Driving substrate;

[0032] 30. Collimation layer; 31. Collimation hole; 301. Metal layer; 302. DBR layer;

[0033] 40. Transparent conductive layer;

[0034] 50. Light-collecting structure;

[0035] 60. Insulating reflective layer;

[0036] 70. Substrate; 71. Contact layer; 72. Bonding metal layer. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this disclosure clearer, the embodiments of this disclosure will be described in further detail below with reference to the accompanying drawings.

[0038] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” “third,” and similar terms used in this patent application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms “an” or “a” and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms “comprising” or “including” and similar terms mean that the elements or objects preceding “comprising” or “including” encompass the elements or objects listed following “comprising” or “including” and their equivalents, and do not exclude other elements or objects. The terms “connected” or “linked” and similar terms are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The terms “upper,” “lower,” “left,” “right,” “top,” and “bottom,” etc., are used only to indicate relative positional relationships, and these relative positional relationships may change accordingly when the absolute position of the described objects changes.

[0039] Figure 1 This is a schematic diagram of the structure of a display panel provided in an embodiment of this disclosure. Figure 1 As shown, the display panel includes: a light-emitting functional layer 10, a driving substrate 20 and a collimation layer 30. The light-emitting functional layer 10 is located on the driving substrate 20 and is electrically connected to the driving substrate 20. The light-emitting functional layer 10 includes a plurality of light-emitting units 100 arranged at intervals.

[0040] like Figure 1 As shown, the collimation layer 30 is located on the side of the light-emitting functional layer 10 away from the driving substrate 20, and the collimation layer 30 has a collimation hole 31 that exposes the light-emitting functional layer 10, and the collimation hole 31 corresponds one-to-one with the light-emitting unit 100.

[0041] The orthographic projection of the light-emitting unit 100 on the surface of the driving substrate 20 is located within the orthographic projection of the corresponding collimation hole 31 on the surface of the driving substrate 20.

[0042] The display panel provided in this embodiment of the present disclosure has a collimation layer 30 disposed on one side of the light-emitting functional layer 10, such that each collimation hole 31 on the collimation layer 30 corresponds one-to-one with a single light-emitting unit 100 in the light-emitting functional layer 10, and the orthographic projection of the light-emitting unit 100 on the surface of the driving substrate 20 is completely within the orthographic projection range of the corresponding collimation hole 31. This requires the light emitted by the light-emitting unit 100 to pass through the collimation hole 31 first, and the aperture and position of the collimation hole 31 are optically designed to allow only light in the target direction to pass through, thus physically restricting the propagation path of stray light in non-target directions.

[0043] Meanwhile, the collimation layer 30 itself acts as a barrier above the surface of the light-emitting unit 100, and the sidewalls of its collimation aperture 31 form vertical or inclined shielding boundaries. When the light-emitting unit 100 emits light, the divergent light beam, which would normally easily diffuse in all directions due to the close arrangement of small-sized chips, is blocked by the aperture wall of the collimation aperture 31. Only light rays along the axis of the collimation aperture 31 or at a narrow angle can pass through smoothly, while lateral stray light toward adjacent light-emitting units 100 is reflected or absorbed by the aperture wall of the collimation aperture 31. This combination of physical shielding and directional light emission directly blocks the possibility of light illuminating adjacent light-emitting units 100, thereby reducing optical crosstalk.

[0044] Furthermore, in related technologies, stray light between adjacent light-emitting units 100 can be superimposed on the display area of ​​the target pixel, resulting in increased background brightness in dark states and decreased light purity of the target pixel in bright states, ultimately leading to blurred contrast in the overall image. However, the collimation layer 30 in this embodiment precisely controls the light emission direction of each light-emitting unit 100, ensuring concentrated light output from the target pixel and effectively suppressing stray light from non-target areas. This results in brighter bright states and darker dark states, effectively improving contrast.

[0045] Optionally, the collimation layer 30 is a conductive film layer, each light-emitting unit 100 is electrically connected to the collimation layer 30, and the collimation layer 30 is electrically connected to the driving substrate 20.

[0046] The collimation layer 30 serves as an intermediate conductive structure, greatly facilitating the transmission of electrical signals. To achieve precise control of the numerous light-emitting units 100, the driving substrate 20 requires stable and reliable electrical connections. The collimation layer 30, made of conductive material, acts as a crucial bridge for electrical signal transmission between the driving substrate 20 and the light-emitting units 100. It can efficiently and accurately distribute the control signals generated by the driving substrate 20 to each light-emitting unit 100, ensuring that each light-emitting unit 100 operates normally according to the instructions of the driving substrate 20, thus achieving precise light emission control.

[0047] Secondly, this connection method simplifies the circuit design of the display panel. What would have required a complex wiring layout to connect the driving substrate 20 and each light-emitting unit 100 can now be achieved through a unified conductive layer, the collimation layer 30. This reduces the complexity and number of lines, lowering the difficulty and cost of circuit design. Simultaneously, it reduces the risk of signal interference and malfunctions that might result from excessive wiring, improving the stability and reliability of the display panel.

[0048] Furthermore, the collimation layer 30 retains its collimation function while achieving conductivity, realizing an integrated design of conductivity and optical control, further improving the integration and performance of the display panel.

[0049] Optionally, the collimation layer 30 includes a metal layer.

[0050] A metal layer is used as the collimation layer 30. By utilizing the good reflective properties of metal, stray light escaping from the side of the light-emitting unit 100 is reflected back to the axial direction of the collimation aperture 31, further reducing light leakage that is not constrained by the collimation aperture 31, thereby improving the directional focusing effect of the light beam and reducing optical crosstalk between adjacent pixels.

[0051] At the same time, by reflecting stray light, more light is redirected to the effective light output direction, which reduces light energy waste, improves luminous efficiency, and avoids the increase in background brightness in dark areas caused by stray light illuminating adjacent pixels, thereby enhancing image contrast.

[0052] For example, the metal layer may be an Al layer.

[0053] The high reflectivity of aluminum can be used to reflect stray light emitted from the side of the light-emitting unit 100 back to the axial direction of the collimating aperture 31, reducing leakage to adjacent pixels.

[0054] In this embodiment, the collimation layer 30 is grid-shaped, meaning the metal layer uses a grid pattern, with the collimation holes 31 corresponding to the perforated mesh holes in the metal layer. The grid lines of the metal layer can serve as both a reflective surface to block stray light and a conductive network connected to the drive substrate 20. This implementation is suitable for compact display panels.

[0055] Figure 2 This is a partial structural schematic diagram of a display panel provided in an embodiment of this disclosure. For example... Figure 2 As shown, the collimation layer 30 includes multiple metal layers 301 stacked alternately and multiple distributed Bragg reflector (DBR) layers.

[0056] like Figure 2 As shown, a through-hole is provided on the DBR layer 302, allowing the metal layers 301 on both sides of the DBR layer 302 to be connected. In this way, the collimation layer 30 can still serve as an intermediate conductive structure to realize the transmission of electrical signals to drive the substrate 20.

[0057] The DBR layer may include multiple alternating layers of first material and multiple layers of second material, with different refractive indices for the first and second material layers.

[0058] For example, one of the first material layer and the second material layer is a TiO2 layer, and the other of the first material layer and the second material layer is a SiO2 layer.

[0059] Among them, the reflection band of the DBR has wavelength selectivity, which can accurately reflect light while allowing other stray wavelengths to pass through, thus enhancing the directional output of effective light.

[0060] In the above implementation, since a DBR layer is set in the collimation layer 30, the DBR layer is optimized for specific wavelengths to improve the reflection efficiency of specific wavelengths, thereby further reducing the loss of target color light and improving color purity.

[0061] Optionally, the display panel further includes a transparent conductive layer 40, which is located on the surface of the light-emitting functional layer 10 away from the driving substrate 20 and is electrically connected to each light-emitting unit 100.

[0062] like Figure 1 As shown, the collimation layer 30 is located on the surface of the transparent conductive layer 40 away from the driving substrate 20.

[0063] In this embodiment, the transparent conductive layer 40 is directly electrically connected to each light-emitting unit 100, serving as a uniform electrical transmission medium. It can more efficiently and stably distribute the electrical signals indirectly transmitted from the driving substrate 20 through the collimation layer 30 to each light-emitting unit 100. Because the transparent conductive layer 40 has good conductivity uniformity, it avoids the problem of uneven light emission caused by localized current concentration, ensuring that each light-emitting unit 100 receives a suitable driving current, thereby guaranteeing the consistency and stability of the light emission of the entire display panel.

[0064] Meanwhile, the transparent conductive layer 40, located on the surface of the light-emitting functional layer 10, provides physical and chemical protection for the light-emitting unit 100. It prevents moisture, oxygen, and other external elements from corroding and damaging the light-emitting unit 100, extending its lifespan. Furthermore, the transparent conductive layer 40 provides a more ideal interface for the subsequent installation of the collimation layer 30. It allows for better bonding between the collimation layer 30 and the light-emitting functional layer 10, ensuring that the collimation layer 30 accurately positions and covers each light-emitting unit 100.

[0065] For example, the transparent conductive layer 40 may be an ITO layer or an IZO layer.

[0066] As an example, the thickness of the transparent conductive layer 40 can be greater than or equal to 2000 angstroms. This thickness range ensures good conductivity for effective transmission of electrical signals while also providing high transparency to reduce obstruction of the light emitted by the light-emitting unit 100.

[0067] Optionally, such as Figure 1 As shown, the display panel also includes a light-collecting structure 50 for focusing light. The light-collecting structure 50 corresponds one-to-one with the collimating hole 31, and the light-collecting structure 50 is located in the corresponding collimating hole 31.

[0068] In the above implementation, a light-collecting structure 50 corresponding to the collimation hole 31 is provided. The light-collecting structure 50 can accurately collect the light from the light-emitting unit 100 after it has been initially constrained by the collimation layer 30, further gather the light energy, enhance the intensity of the emitted light, and make the display screen brighter and clearer, especially in scenes with strong ambient light, it can also ensure visibility.

[0069] Furthermore, the light-collecting structure 50 optimizes the light-emitting angle, concentrating the light into a specific optimal viewing angle range and reducing ineffective scattered light. This not only improves light energy utilization but also enhances the contrast and depth of the image. Simultaneously, the precise correspondence between the light-collecting structure 50 and the collimating aperture 31 ensures that each light-emitting unit 100 has an independent light-focusing channel, preventing interference between light from different light-emitting units 100, effectively suppressing light crosstalk, and further improving the clarity and accuracy of the display.

[0070] Optionally, such as Figure 1As shown, the surface of the light-collecting structure 50 that is away from the driving substrate 20 is an arc surface.

[0071] In the above implementation, by setting the surface of the light-collecting structure 50 as a convex arc surface, the obliquely escaping light can be guided to redirect to the effective light-emitting area, further reducing light crosstalk between adjacent pixels and improving contrast in conjunction with the collimation layer 30.

[0072] For example, the surface of the light-collecting structure 50 is spherical. The spherical structure has a universal light-gathering effect, which is especially suitable for omnidirectional Micro LED chips. The hemispherical arc surface can symmetrically refract light incident from all angles, uniformly enhancing the overall brightness.

[0073] In this embodiment of the disclosure, the curvature of the arc surface can be precisely designed to compensate for the differences in light output brightness at different positions of the light-emitting unit 100.

[0074] Because the light emission from different positions of the light-emitting unit 100 may vary—for example, the center of the light-emitting unit 100 may emit strong light while the edges may emit weak light—the curvature of the arc surface in that area can be designed to be relatively small to allow the light to diffuse appropriately and avoid excessive concentration that could lead to localized overbrightness. Conversely, for areas where the light emission from the edges of the light-emitting unit 100 is weak, the curvature can be increased to enhance the refraction and focusing of light, directing more edge light towards the effective emission direction and improving edge brightness. This differentiated curvature design ensures that the light emitted from different positions is more uniform overall, preventing localized overbrightness or underbrightness and resulting in a more uniform brightness of the displayed image.

[0075] Alternatively, the light-collecting structure 50 can be made of PDMS, PMMA, or silicon dioxide.

[0076] Polydimethylsiloxane (PDMS) is a flexible and bendable material; its light transmittance exceeds 90%, which reduces total reflection and makes it suitable for flexible Micro LED panels.

[0077] Among them, polymethyl methacrylate (PMMA) has a light transmittance of over 92%, good optical uniformity, moderate mechanical strength, good weather resistance, and is easy to mold, making it suitable for preparing light-collecting structures for large-area planar displays.

[0078] Among them, silicon dioxide has a light transmittance of over 95% and excellent thermal stability, and can be precisely processed into microstructures through etching, making it suitable for high-temperature processes and high-precision display requirements.

[0079] Optionally, such as Figure 1 As shown, the thickness of the light-collecting structure 50 is less than or equal to the depth of the collimating hole 31.

[0080] In the above implementation, the light-collecting structure 50 is completely embedded within the collimating aperture 31. Its curved surface can directly receive the light constrained by the collimating layer 30, thereby reducing light scattering out of the aperture and ensuring that more effective light energy is directionally focused, thus improving light extraction efficiency. The collimating aperture 31 itself limits the light divergence range through its physical aperture. When the thickness of the light-collecting structure 50 does not exceed its depth, it will not destroy the initial blocking effect of the collimating layer 30 on stray light. The two work together to enhance the directionality of the beam.

[0081] Optionally, such as Figure 1 As shown, the display panel also includes an insulating reflective layer 60, which is located on the driving substrate 20 and fills the gaps between the plurality of light-emitting units 100. The collimation layer 30 is located on the surface of the insulating reflective layer 60 away from the driving substrate 20.

[0082] The insulating reflective layer 60 ensures that the electrical signals of the driving substrate 20 are transmitted directionally only through the light-emitting units 100, preventing leakage or short circuits between the light-emitting units 100 and improving circuit stability. Furthermore, the insulating reflective layer 60 reflects non-target light rays that escape into the gaps from the sides or bottom of the light-emitting units 100 back to the collimating aperture 31, reducing light energy waste and enhancing effective light emission intensity.

[0083] Meanwhile, the insulating reflective layer 60 fills the gaps to form a flat surface, providing uniform support for the collimation layer 30, ensuring that the collimation hole 31 is precisely aligned with the light-emitting unit 100, avoiding collimation deviation caused by uneven gaps, and simplifying the manufacturing process of the collimation layer 30.

[0084] For example, the insulating reflective layer 60 may be at least one of a silicon oxide layer, a titanium oxide layer, and an epoxy resin layer.

[0085] For example, the insulating reflective layer 60 may be a plurality of alternating layers of silicon oxide and a plurality of layers of titanium oxide to form a distributed Bragg mirror layer.

[0086] For example, the thickness of the insulating reflective layer is 1.5 μm to 2.5 μm.

[0087] Optionally, the thickness of the insulating reflective layer 60 is greater than or equal to the thickness of the light-emitting unit 100.

[0088] When the thickness of the insulating reflective layer 60 is not less than the height of the light-emitting unit 100, it can ensure that all gaps are filled, avoid light scattering caused by residual air gaps due to insufficient filling, and allow all light to be directionally reflected to the collimating hole 31, thereby improving the light energy utilization rate.

[0089] Furthermore, the thicker insulating reflective layer 60 can completely isolate the lateral leakage path between the light-emitting unit 100 and the driving substrate 20, avoiding the risk of short circuit. As the direct support substrate of the collimation layer 30, the insulating reflective layer 60 has sufficient thickness to provide a flat and uniform surface, avoiding local unevenness caused by insufficient gap filling, ensuring that the collimation hole 31 and the light-emitting unit 100 are accurately aligned, preventing collimation deviation caused by the undulation of the reflective layer, and ensuring the consistency of optical performance.

[0090] For example, the thickness of the insulating reflective layer 60 is 500 to 1000 angstroms greater than the thickness of the light-emitting unit 100.

[0091] The insulating reflective layer 60 is 500 to 1000 angstroms thicker than the light-emitting unit 100. This not only completely fills the gap and blocks leakage, but also avoids the overall thickness being affected by excessive thickness. The slight thickness difference ensures that there is no residual air in the gap, efficiently reflecting light to the collimation hole 31, while precisely supporting the collimation layer 30, ensuring optical alignment accuracy and improving light efficiency and stability.

[0092] Optionally, such as Figure 1 As shown, each light-emitting unit 100 includes a first semiconductor layer 11, a multiple quantum well layer 12, and a second semiconductor layer 13 stacked sequentially.

[0093] In this embodiment of the present disclosure, one of the first semiconductor layer 11 and the second semiconductor layer 13 is a p-type layer, and the other of the first semiconductor layer 11 and the second semiconductor layer 13 is an n-type layer.

[0094] As an example, the first semiconductor layer 11 is an n-type layer and the second semiconductor layer 13 is a p-type layer.

[0095] Optionally, the first semiconductor layer 11 is an n-type GaN layer. The thickness of the n-type GaN layer can be from 0.5 μm to 1 μm.

[0096] Optionally, the multiple quantum well layer 12 includes alternating InGaN quantum well layers and GaN quantum barrier layers. Specifically, the multiple quantum well layer 12 may include 3 to 8 alternating stacked InGaN quantum well layers and GaN quantum barrier layers.

[0097] As an example, in an embodiment of this disclosure, the multi-quantum-well layer 12 includes five alternating stacked InGaN quantum-well layers and GaN quantum-barrier layers.

[0098] Optionally, the thickness of the multiple quantum well layer 12 can be from 150 nm to 200 nm.

[0099] Optionally, the second semiconductor layer 13 is a p-type GaN layer. The thickness of the p-type GaN layer can be from 0.5 μm to 1 μm.

[0100] Optionally, such as Figure 1As shown, the display panel also includes a bonding metal layer 72 and a contact layer 71. The bonding metal layer 72 is located on the driving substrate 20, and the contact layer 71 is located on the surface of the light-emitting unit 100 near the driving substrate 20. The contact layer 71 of each light-emitting unit 100 is connected to the bonding metal layer 72.

[0101] For example, the contact layer may be at least one of a metal layer and a transparent conductive layer.

[0102] For example, the contact layer can be an ITO layer or an IZO layer.

[0103] Optionally, the driving substrate 20 may be a complementary metal-oxide-semiconductor (CMOS) integrated circuit board.

[0104] like Figure 1 As shown, an electrode block corresponding to each light-emitting unit 100 is provided on the driving substrate 20. Each light-emitting unit 100 has a bonding metal layer 72 on the side close to the driving substrate 20. The bonding metal layer 72 of each light-emitting diode is electrically connected to the corresponding electrode block, so as to realize the purpose of the driving substrate 20 controlling the operation of each light-emitting diode.

[0105] For example, the bonding metal layer 72 may include at least one of an AuBe layer, an Au layer, a Ti layer, a Ni layer, and a Pt layer.

[0106] Figure 3 This is a flowchart illustrating a method for manufacturing a display panel according to an embodiment of this disclosure. Figure 3 As shown, the preparation method includes:

[0107] S11: A light-emitting functional layer 10 is formed on the substrate 70.

[0108] For example, the substrate 70 is a sapphire substrate 70. The sapphire substrate 70 has high light transmittance, that is, the substrate 70 is a transparent substrate 70. In addition, sapphire material is relatively hard and has relatively stable chemical properties, which enables the light-emitting diode to have good light-emitting effect and stability.

[0109] For example, such as Figure 4 As shown, the light-emitting functional layer 10 may include a first semiconductor layer 11, a multiple quantum well layer 12, and a second semiconductor layer 13 sequentially stacked on the substrate 70.

[0110] The first semiconductor layer 11 has a first conductivity type, the second semiconductor layer 13 has a second conductivity type different from the first conductivity type, and the multi-quantum well layer 12 is used to generate light through electron-hole recombination.

[0111] Among them, one of the first semiconductor layer 11 and the second semiconductor layer 13 is a p-type layer, and the other of the first semiconductor layer 11 and the second semiconductor layer 13 is an n-type layer.

[0112] As an example, the first semiconductor layer 11 is an n-type layer and the second semiconductor layer 13 is a p-type layer.

[0113] Optionally, the first semiconductor layer 11 is an n-type GaN layer. The thickness of the n-type GaN layer can be from 0.5 μm to 1 μm.

[0114] Optionally, the multiple quantum well layer 12 includes alternating InGaN quantum well layers and GaN quantum barrier layers. Specifically, the multiple quantum well layer 12 may include 3 to 8 alternating stacked InGaN quantum well layers and GaN quantum barrier layers.

[0115] As an example, in an embodiment of this disclosure, the multi-quantum-well layer 12 includes five alternating stacked InGaN quantum-well layers and GaN quantum-barrier layers.

[0116] Optionally, the thickness of the multiple quantum well layer 12 can be from 150 nm to 200 nm.

[0117] Optionally, the second semiconductor layer 13 is a p-type GaN layer. The thickness of the p-type GaN layer can be from 0.5 μm to 1 μm.

[0118] After growing the light-emitting functional layer 10 in step S11, the process may further include growing a contact layer on the surface of the light-emitting functional layer 10.

[0119] For example, the contact layer may be at least one of a metal layer and a transparent conductive layer.

[0120] For example, the contact layer can be an ITO layer or an IZO layer.

[0121] S12: Bond the light-emitting functional layer 10 to the driving substrate 20 and remove the substrate 70 to make the light-emitting functional layer 10 electrically connected to the driving substrate 20.

[0122] like Figure 4 As shown, step S12 may include: forming a bonding metal layer 72 on the surface of both the driving substrate 20 and the contact layer 71, and bonding the contact layer 71 and the driving substrate 20 together.

[0123] The bonding metal layer 72 may include at least one of a titanium layer, a platinum layer, a gold layer, an aluminum layer, and a tin layer.

[0124] Next, as Figure 4 As shown, the substrate 70 is removed, and part of the surface light-emitting functional layer 10 is removed by etching and other methods. The final thickness of the remaining light-emitting functional layer 10 is between 0.9 μm and 1.4 μm.

[0125] S13: Graphical processing of the light-emitting functional layer 10 to form multiple spaced light-emitting units 100.

[0126] like Figure 5 As shown, step S13 may include: forming a contact conductive layer on the surface of the light-emitting functional layer 10, and then performing array etching of the light-emitting units 100 to remove the light-emitting functional layer 10 and the bonding metal layer 72 in the non-patterned area.

[0127] For example, such as Figure 5 As shown, the graphically processed light-emitting functional layer 10 includes multiple trapezoidal light-emitting units 100.

[0128] The following steps may also be included before step S14:

[0129] like Figure 6 As shown, an insulating reflective layer 60 is formed on the surface of the driving substrate 20, and then the insulating reflective layer 60 is ground flat so that the thickness of the insulating reflective layer 60 is 500 to 1000 angstroms greater than the thickness of the light-emitting unit 100; then the insulating reflective layer 60 on the top of the light-emitting unit 100 is cut open to form a through hole exposing the light-emitting unit 100.

[0130] For example, the insulating reflective layer 60 may be at least one of a silicon oxide layer, a titanium oxide layer, and an epoxy resin layer.

[0131] For example, the insulating reflective layer 60 may be a plurality of alternating layers of silicon oxide and a plurality of layers of titanium oxide to form a distributed Bragg mirror layer.

[0132] For example, the thickness of the insulating reflective layer is 1.5 μm to 2.5 μm.

[0133] like Figure 6 As shown, the insulating reflective layer 60 and the light-emitting unit 100 are covered by a transparent conductive layer 40.

[0134] The transparent conductive layer 40 is disposed above the insulating reflective layer, and the transparent conductive layer 40 is electrically connected to each light-emitting unit 100 through through holes.

[0135] For example, the thickness of the transparent conductive layer 40 is greater than or equal to 2000 angstroms.

[0136] S14: A collimation layer 30 is formed on the side of the light-emitting functional layer 10 away from the driving substrate 20.

[0137] like Figure 6As shown, the collimation layer 30 has a collimation hole 31 that exposes the light-emitting functional layer 10. The collimation hole 31 corresponds one-to-one with the light-emitting unit 100. The orthographic projection of the light-emitting unit 100 on the surface of the driving substrate 20 is located within the orthographic projection of the corresponding collimation hole 31 on the surface of the driving substrate 20.

[0138] Specifically, it may include: a metal conductive mesh structure is provided on the transparent conductive layer 40, and the mesh of the metal conductive mesh structure corresponds to each collimation hole 31 to form the collimation layer 30.

[0139] The conductive metal mesh structure is electrically connected to the integrated circuit of the driving substrate 20.

[0140] Optionally, the collimation layer 30 includes a metal layer. For example, the metal layer may be an Al layer.

[0141] Step S14 may further include: forming a light-collecting structure 50 within the collimation aperture 31.

[0142] Optionally, such as Figure 1 As shown, the surface of the light-collecting structure 50 that is away from the driving substrate 20 is an arc surface.

[0143] For example, the surface of the light-collecting structure 50 is spherical. The spherical structure has a universal light-gathering effect, which is especially suitable for omnidirectional Micro LED chips. The hemispherical arc surface can symmetrically refract light incident from all angles, uniformly enhancing the overall brightness.

[0144] Alternatively, the light-collecting structure 50 can be made of PDMS, PMMA, or silicon dioxide.

[0145] Optionally, such as Figure 1 As shown, the thickness of the light-collecting structure 50 is less than or equal to the depth of the collimating hole 31.

[0146] The display panel fabricated by the method provided in this disclosure has a collimation layer on one side of the light-emitting functional layer, so that each collimation hole on the collimation layer corresponds one-to-one with a single light-emitting unit in the light-emitting functional layer, and the orthographic projection of the light-emitting unit on the surface of the driving substrate is completely within the orthographic projection range of the corresponding collimation hole. This requires the light emitted by the light-emitting unit to pass through the collimation hole first, and the aperture and position of the collimation hole are optically designed to allow only light in the target direction to pass through, thus physically restricting the propagation path of stray light in non-target directions.

[0147] Meanwhile, the collimation layer itself acts as a barrier above the surface of the light-emitting unit, and the sidewalls of its collimation aperture form vertical or inclined shielding boundaries. When the light-emitting unit emits light, the divergent beam, which would normally easily diffuse in all directions due to the close arrangement of small-sized chips, is blocked by the aperture walls. Only light rays along the collimation aperture axis or at narrow angles can pass through smoothly, while lateral stray light towards adjacent light-emitting units is reflected or absorbed by the aperture walls. This combination of physical shielding and directional light emission directly blocks the possibility of light illuminating adjacent light-emitting units, thereby reducing optical crosstalk.

[0148] Furthermore, in related technologies, stray light between adjacent light-emitting units can superimpose onto the display area of ​​the target pixel, resulting in increased background brightness in dark states and decreased light purity of the target pixel in bright states, ultimately leading to blurred contrast in the overall image. However, the collimation layer in this embodiment precisely controls the light emission direction of each light-emitting unit, ensuring concentrated light output from the target pixel and effectively suppressing stray light from non-target areas. This results in brighter bright states and darker dark states, effectively improving contrast.

[0149] The above description is merely an optional embodiment of this disclosure and is not intended to limit this disclosure. The data therein represents only illustrative examples. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the protection scope of this disclosure.

Claims

1. A display panel, characterized in that, The display panel includes: a light-emitting functional layer (10), a driving substrate (20) and a collimation layer (30). The light-emitting functional layer (10) is located on the driving substrate (20) and is electrically connected to the driving substrate (20). The light-emitting functional layer (10) includes a plurality of light-emitting units (100) arranged at intervals. The collimation layer (30) is located on the side of the light-emitting functional layer (10) away from the driving substrate (20), and the collimation layer (30) has a collimation hole (31) that exposes the light-emitting functional layer (10). The collimation hole (31) corresponds one-to-one with the light-emitting unit (100). The orthographic projection of the light-emitting unit (100) on the surface of the driving substrate (20) is located within the orthographic projection of the corresponding collimation hole (31) on the surface of the driving substrate (20).

2. The display panel according to claim 1, characterized in that, The collimation layer (30) is a conductive film layer, and each of the light-emitting units (100) is electrically connected to the collimation layer (30), and the collimation layer (30) is electrically connected to the driving substrate (20).

3. The display panel according to claim 2, characterized in that, The collimation layer (30) includes a metal layer.

4. The display panel according to claim 2, characterized in that, The display panel further includes a transparent conductive layer (40), which is located on the surface of the light-emitting functional layer (10) away from the driving substrate (20) and is electrically connected to each of the light-emitting units (100). The collimation layer (30) is located on the surface of the transparent conductive layer (40) away from the driving substrate (20).

5. The display panel according to claim 1, characterized in that, The display panel also includes a light-collecting structure (50) for focusing light, the light-collecting structure (50) corresponding one-to-one with the collimating hole (31), and the light-collecting structure (50) is located in the corresponding collimating hole (31).

6. The display panel according to claim 5, characterized in that, The surface of the light-collecting structure (50) away from the driving substrate (20) is an arc surface.

7. The display panel according to claim 5, characterized in that, The thickness of the light-collecting structure (50) is less than or equal to the depth of the collimating hole (31).

8. The display panel according to any one of claims 1 to 7, characterized in that, The display panel further includes an insulating reflective layer (60) located on the driving substrate (20) and filling the gaps between the plurality of light-emitting units (100), and the collimation layer (30) located on the surface of the insulating reflective layer (60) away from the driving substrate (20).

9. The display panel according to claim 8, characterized in that, The thickness of the insulating reflective layer (60) is greater than or equal to the thickness of the light-emitting unit (100).

10. A method for manufacturing a display panel, characterized in that, The preparation method includes: A light-emitting functional layer (10) is formed on the substrate (70); The light-emitting functional layer (10) is bonded to the driving substrate (20), and the substrate (70) is removed, so that the light-emitting functional layer (10) is electrically connected to the driving substrate (20); The light-emitting functional layer (10) is graphically processed to form multiple light-emitting units (100) arranged at intervals; A collimation layer (30) is formed on the side of the light-emitting functional layer (10) away from the driving substrate (20). The collimation layer (30) has a collimation hole (31) that exposes the light-emitting functional layer (10). The collimation hole (31) corresponds one-to-one with the light-emitting unit (100). The orthographic projection of the light-emitting unit (100) on the surface of the driving substrate (20) is located within the orthographic projection of the corresponding collimation hole (31) on the surface of the driving substrate (20).

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