Nanowire display device and display device

Abstract

The invention discloses a nanowire display device and a display device, and relates to the technical field of micro-display, the nanowire display device comprises a substrate and a plurality of pixel units arranged on the substrate; each pixel unit comprises a plurality of nanowire light-emitting structures, and the nanowire light-emitting structures of different pixel units are used for emitting light of the same color or different colors; the nanowire light-emitting structures of all the pixel units are arranged in a periodic change mode in the direction from the center to the edge of the nanowire display device so as to adjust the light-emitting angle of the corresponding area of the nanowire display device. According to the scheme, angle regulation and control are achieved through periodic changes of the nanowire light-emitting structure array, the distance or size of the nanowire light-emitting structures is accurately controlled through the semiconductor technology, error accumulation of a secondary optical element is eliminated, and the adaptability of the nanowire display device to an optical-mechanical system is improved.

Description

Technical Field

[0001] This invention relates to the field of microdisplay technology, and in particular to a nanowire display device and display apparatus. Background Technology

[0002] With the rapid development of AR technology, Micro LED display technology has become an ideal choice for near-eye display devices due to its ultra-high brightness, high contrast, and low power consumption. In the AR optical architecture, the collaborative design of the microdisplay and the optomechanical system is particularly critical. The optomechanical system, which adopts asymmetric optical path designs such as freeform prisms, requires the microdisplay to have spatially modulated light emission characteristics, that is, the light emission angle of different display areas needs to be precisely matched with the incident angle of the optomechanical system.

[0003] The current mainstream technical solution achieves light angle control by integrating a microlens array on the light-emitting side of the Micro LED pixel array. This involves offsetting the relative positions of the microlenses to the corresponding pixel units, causing the light emitted by the Micro LED pixel units to be deflected at an angle after passing through the microlenses. By changing the offset of the microlenses in different areas, the light emission angle in different areas of the display panel can be shifted at different angles.

[0004] However, the adjustment accuracy of the light emission angle in the above scheme is highly dependent on factors such as the machining accuracy of the microlens curvature radius and the assembly and positioning deviation between the microlens and the pixel unit. This makes it impossible to accurately adapt to the optical path design of the optomechanical system, affecting the user experience of AR devices. Summary of the Invention

[0005] The main objective of this invention is to propose a nanowire display device and display apparatus, which aims to solve the problem of poor adjustment accuracy of the light emission angle of existing micro-display devices.

[0006] To achieve the above objectives, the present invention proposes a nanowire display device, which includes a substrate and a plurality of pixel units disposed on the substrate;

[0007] Each pixel unit includes multiple nanowire light-emitting structures, and the multiple nanowire light-emitting structures of different pixel units are used to emit light of the same or different colors;

[0008] Along the direction from the center to the edge of the nanowire display device, the nanowire light-emitting structure of each pixel unit is arranged in a periodic variation to adjust the light emission angle of the corresponding area of ​​the nanowire display device.

[0009] In one embodiment of the present invention, each pixel unit includes a sub-pixel, and a plurality of nanowire light-emitting structures in the sub-pixel are uniformly spaced apart. Along the direction from the center to the edge of the nanowire display device, the spacing between two adjacent nanowire light-emitting structures in the plurality of pixel units gradually decreases or gradually increases.

[0010] In one embodiment of the present invention, each pixel unit includes a first sub-pixel, a second sub-pixel, and a third sub-pixel, wherein the first sub-pixel, the second sub-pixel, and the third sub-pixel each include a plurality of uniformly spaced nanowire light-emitting structures.

[0011] The spacing between two adjacent nanowire light-emitting structures in the first sub-pixel is D1, the spacing between two adjacent nanowire light-emitting structures in the second sub-pixel is D2, and the spacing between two adjacent nanowire light-emitting structures in the third sub-pixel is D3.

[0012] Along the direction from the center to the edge of the nanowire display device, D1 in the plurality of pixel units gradually decreases or gradually increases, D2 in the plurality of pixel units gradually decreases or gradually increases, and D3 in the plurality of pixel units gradually decreases or gradually increases.

[0013] In one embodiment of the present invention, the cross-sectional size of the nanowire light-emitting structure in the first sub-pixel is smaller than the cross-sectional size of the nanowire light-emitting structure in the second sub-pixel, the cross-sectional size of the nanowire light-emitting structure in the second sub-pixel is smaller than the cross-sectional size of the nanowire light-emitting structure in the third sub-pixel, the first sub-pixel is a red light sub-pixel, the second sub-pixel is a green light sub-pixel, and the third sub-pixel is a blue light sub-pixel.

[0014] In one embodiment of the present invention, 170nm≤D1≤690nm, 150nm≤D2≤510nm, and 130nm≤D3≤430nm.

[0015] In one embodiment of the present invention, the pixel unit includes at least one sub-pixel, and the plurality of nanowire light-emitting structures in the sub-pixel are arranged in a triangular, rectangular or honeycomb array;

[0016] And / or, the shape of the nanowire luminescent structure is cylindrical.

[0017] In one embodiment of the present invention, the nanowire display device further includes a common electrode layer, each pixel unit includes at least one sub-pixel, each sub-pixel includes a metal electrode layer and a plurality of nanowire light-emitting structures disposed on the metal electrode layer, the metal electrode layer is disposed on the substrate, and the common electrode layer is disposed on the side of the nanowire light-emitting structure away from the metal electrode layer.

[0018] The nanowire light-emitting structure includes an n-type doped layer, a nanowire light-emitting layer, and a p-type doped layer sequentially stacked between the metal electrode layer and the common electrode layer, wherein the p-type doped layer is disposed on the metal electrode layer.

[0019] In one embodiment of the present invention, a plurality of nanowire light-emitting structures are arranged at intervals on the substrate, and the gaps between adjacent nanowire light-emitting structures are filled with insulating and light-transmitting material to form a planarization layer.

[0020] In one embodiment of the present invention, the refractive index difference between the planarization layer and the nanowire light-emitting structure is η, where η ≥ 0.2.

[0021] The present invention also proposes a display device comprising a nanowire display device as described in any of the above descriptions.

[0022] The nanowire display device proposed in this invention includes a substrate and multiple pixel units disposed on the substrate. Each pixel unit includes multiple nanowire light-emitting structures, and the multiple nanowire light-emitting structures of different pixel units can emit light of the same or different colors. The nanowire light-emitting structures can be indium gallium nitride (InGaN) nanowires, zinc oxide (ZnO) nanowires, or cadmium selenide (CdS) nanowires, etc. For example, when the nanowire light-emitting structure is indium gallium nitride (InGaN), the indium content can be changed to make the nanowire light-emitting structure emit red, green, or blue light. Along the direction from the center to the edge of the nanowire display device, the nanowire light-emitting structures of each pixel unit exhibit periodic changes. For example, the spacing between two nanowire light-emitting structures can be set to gradually increase or decrease along the direction from the center to the edge of the nanowire display device, or the size of each nanowire light-emitting structure can be gradually changed along the direction from the center to the edge of the nanowire display device. Under the action of this periodically changing microstructure, light waves will be deflected at different angles.

[0023] Therefore, this application can control the periodic changes of the nanowire light-emitting structure in multiple pixel units to make light emitted from different areas of the nanowire display device emit at different offset angles, thus adapting to the optical path design of the optomechanical system. Since this nanowire light-emitting structure is formed on the substrate surface using semiconductor technology, compared to existing microlens array technology, it solves the problem that the adjustment accuracy of the light emission angle is affected by the position and curvature of the microlens, improving the accuracy of optical path adaptation to the optomechanical system and enhancing the user experience. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the structure of an embodiment of the nanowire display device provided by the present invention;

[0026] Figure 2 for Figure 1 Schematic diagram of the structure at point A1;

[0027] Figure 3 for Figure 1 A magnified view of a portion of point Ax;

[0028] Figure 4 for Figure 2 Internal structure diagram;

[0029] Figure 5 for Figure 3 Internal structure diagram;

[0030] Figure 6 A schematic diagram of another embodiment of the nanowire display device provided by the present invention;

[0031] Figure 7 for Figure 6 Schematic diagram of the structure at G1, G1L, and G1R.

[0032] Explanation of icon numbers:

[0033] 10. Pixel unit; 101. First sub-pixel; 102. Second sub-pixel; 103. Third sub-pixel; 11. Planarization layer; 12. Nanowire light-emitting structure; 121. p-type doped layer; 122. Nanowire light-emitting layer; 123. n-type doped layer; 13. Metal electrode layer; 20. Substrate; 30. Common electrode layer.

[0034] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0036] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0037] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0038] In existing technologies, with the widespread adoption of augmented reality devices, the co-design of microdisplays and optomechanical systems faces challenges. Traditional solutions rely on microlens arrays to control the angle of light, but manufacturing errors and assembly deviations in the curvature radius of the microlenses limit the precision of the light-emitting angle adjustment, making it difficult to match the optical design requirements of asymmetric optical paths. When applied to freeform prism optomechanical systems, deviations in the incident angle of light at the edge of the display panel may cause image distortion or uneven brightness, affecting the user experience.

[0039] To address the aforementioned issues and the insufficient angle control due to limitations in microlens fabrication precision, the inventors attempted to improve the optical properties of the light-emitting structure itself. By analyzing the influence of the nanowire light-emitting array structure on the direction of light propagation, they discovered that altering the arrangement period of the nanowire light-emitting structure directly affects the light emission angle.

[0040] Based on this, the present invention proposes a nanowire display device.

[0041] Combination Figures 1 to 5 As shown, in one embodiment of the present invention, the nanowire display device includes a substrate 20 and a plurality of pixel units 10 disposed on the substrate 20;

[0042] Each pixel unit 10 includes multiple nanowire light-emitting structures 12, and the multiple nanowire light-emitting structures 12 of different pixel units 10 are used to emit light of the same or different colors.

[0043] Along the direction from the center to the edge of the nanowire display device, the nanowire light-emitting structure 12 of each pixel unit 10 is arranged in a periodic variation to adjust the light emission angle of the corresponding area of ​​the nanowire display device.

[0044] In this context, a pixel unit 10 refers to the smallest functional unit in a nanowire display device that enables independent light emission control. The nanowire display device includes multiple pixel units 10, arranged in a matrix to form a display area. The nanowire light-emitting structure 12 is a semiconductor nanowire with light-emitting properties, specifically fabricated using molecular beam epitaxy (MBE) to selectively grow materials such as indium gallium nitride (InGaN) or zinc oxide on a substrate 20. The nanowire light-emitting structure 12 can emit different colors of light. For example, when the nanowire light-emitting structure 12 is InGaN, changing the indium content can make it emit red, green, or blue light. By controlling the emitted color of the nanowire light-emitting structure 12 in different pixel units 10, monochrome or full-color display can be achieved. The diameter of a single nanowire light-emitting structure 12 is 50nm-200nm, and its height is 1µm-10µm. The substrate 20 includes a silicon substrate and a pixel driving circuit disposed on the silicon substrate. The pixel unit 10 is electrically connected to the pixel driving circuit.

[0045] The periodic variation of the nanowire light-emitting structure 12 refers to the regular gradient distribution of the periodic arrangement parameters of the nanowire light-emitting structure 12. For example, changing the spacing or size of adjacent nanowire light-emitting structures 12 in different pixel units 10 will affect the light emission angle. Therefore, according to the incident angle requirements of the optomechanical system, changing the periodic arrangement parameters of the nanowire light-emitting structure 12 in the corresponding pixel unit 10 can achieve optical path adaptation between the nanowire display device and the optomechanical system.

[0046] Compared to existing technologies, traditional methods indirectly adjust the light direction by shifting microlenses, while this method directly utilizes the intrinsic optical properties of the nanowire light-emitting structure array 12 to achieve angle control. In microlens solutions, the angle adjustment accuracy is limited by lens curvature and assembly tolerances, while this method precisely controls the spacing or size of the nanowire light-emitting structure 12 through semiconductor processes, eliminating the accumulation of errors from secondary optical elements.

[0047] Through the above technical solution, this application achieves precise matching of the light emission angles of different regions in the nanowire display device, meeting the incident angle requirements of the optomechanical system. Since the angle adjustment function is integrated within the light-emitting structure, no additional microlens components are required, reducing system complexity and improving the optical matching accuracy with the optomechanical system. Therefore, this solution can effectively improve the spot shift caused by microlens size deviations and assembly errors in traditional solutions, enhancing the image quality and visual comfort of augmented reality devices.

[0048] Combination Figure 6 and Figure 7 As shown, in one embodiment of the present invention, each pixel unit 10 includes a sub-pixel, and a plurality of nanowire light-emitting structures 12 in the sub-pixel are evenly spaced. Along the direction from the center to the edge of the nanowire display device, the spacing between two adjacent nanowire light-emitting structures 12 in the plurality of pixel units 10 gradually decreases or gradually increases.

[0049] In this embodiment, each sub-pixel is the smallest light-emitting unit that is independently controlled to emit light, and each pixel unit 10 includes one sub-pixel to achieve monochrome display. The nanowire light-emitting structures 12 in the sub-pixel are arranged at uniform intervals on the substrate 20. This arrangement makes the light emission intensity and light emission angle of a single pixel unit 10 more uniform in space, thereby improving the display effect of the nanowire display device and improving the adjustment accuracy of the light emission angle in different areas.

[0050] refer to Figure 6 and Figure 7 It can be seen that the pixel unit 10 located at the center of the nanowire display device is G1, and the spacing between the multiple nanowire light-emitting structures 12 in the G1 pixel unit is D2, and the light emitted is directed in the vertical direction (that is, perpendicular to the substrate 20); the pixel unit 10 located at the edge of the nanowire display device and to the left of the G1 pixel unit is G1L, and the spacing between the multiple nanowire light-emitting structures 12 in the G1L pixel unit is D2L; the pixel unit 10 located at the edge of the nanowire display device and to the right of the G1 pixel unit is G1R, and the spacing between the multiple nanowire light-emitting structures 12 in the G1R pixel unit is D2R.

[0051] Where D2L≠D2 and D2R≠D2, the light emitted by the G1L and G1R pixel units has a certain tilt angle, such as 10 degrees, 300 degrees, or 60 degrees with the vertical direction. By gradually decreasing or increasing the spacing between two adjacent nanowire light-emitting structures 12 in the multiple pixel units 10, that is, by making the nanowire light-emitting structures 12 in the multiple pixel units 10 exhibit periodic gradients, the pixel unit 10 located in the center of the nanowire display device emits light in the vertical direction, while the deflection angle of the light emitted by each pixel unit 10 gradually increases along the direction from the center to the edge, so as to better adapt to the optomechanical system and improve the user's wearing experience.

[0052] Specifically, the spacing parameter between two adjacent nanowire light-emitting structures 12 affects the phase matching condition of the light field. The essence of the phase matching condition is the principle of momentum conservation during wave propagation. The phase matching condition is: sinθ+1 / D=neff / λ, where D is the spacing between adjacent nanowire light-emitting structures 12, λ is the resonant wavelength, neff is the effective refractive index, and θ is the emission angle. Since the emission wavelength range of the pixel unit 10 is fixed when it emits light of the corresponding color (i.e., λ can be considered constant), and under a fixed material system (specific thickness and composition), the fluctuation amplitude of the equivalent refractive index neff can be suppressed to a negligible range in engineering and can be regarded as a constant parameter. Therefore, by presetting the gradient change of the spacing between adjacent nanowire light-emitting structures 12 in different pixel units 10, the continuous adjustment of the emission angle θ can be precisely controlled. For example, the spacing between the nanowire light-emitting structures 12 in the central region is set to a smaller value to match the vertical incident requirements of the optomechanical system, while the spacing in the edge region is gradually increased so that the emission angle gradually shifts relative to the vertical direction, thereby matching the optical path design requirements of the optomechanical system.

[0053] In other embodiments, the size of multiple nanowire light-emitting structures 12 in the same pixel unit 10 can be adjusted so that the size of the multiple nanowire light-emitting structures 12 gradually changes in a specific direction, thereby causing the light to deflect in a specific direction. By changing the periodic characteristics of the nanowire light-emitting structures 12 in this way, the emission angle can also be adjusted, thereby better matching the optomechanical system.

[0054] Combination Figures 1 to 5 As shown, in one embodiment of the present invention, each pixel unit 10 includes a first sub-pixel 101, a second sub-pixel 102 and a third sub-pixel 103, and the first sub-pixel 101, the second sub-pixel 102 and the third sub-pixel 103 each include a plurality of uniformly spaced nanowire light-emitting structures 12.

[0055] The spacing between two adjacent nanowire light-emitting structures 12 in the first sub-pixel 101 is D1, the spacing between two adjacent nanowire light-emitting structures 12 in the second sub-pixel 102 is D2, and the spacing between two adjacent nanowire light-emitting structures 12 in the third sub-pixel 103 is D3.

[0056] Along the direction from the center to the edge of the nanowire display device, D1 in the multiple pixel units 10 gradually decreases or gradually increases, D2 in the multiple pixel units 10 gradually decreases or gradually increases, and D3 in the multiple pixel units 10 gradually decreases or gradually increases.

[0057] In this embodiment, a single pixel unit 10 is divided into three independent light-emitting regions. The three sub-pixels can change the light-emitting color by changing the indium content of their nanowire light-emitting structure 12, so that the first sub-pixel 101, the second sub-pixel 102 and the third sub-pixel 103 can emit the same or different colors of light respectively, thereby achieving monochrome or full-color display.

[0058] Among them, the spacing parameters D1, D2, and D3 refer to the center distance between adjacent nanowire light-emitting structures 12. In the same pixel unit 10, D1, D2, and D3 can be the same or different. In different pixel units 10, the spacing between the nanowire light-emitting structures 12 is set to be different, thereby making the light emission angle of different pixel units 10 different.

[0059] Specifically, such as Figure 1 As shown, each pixel unit 10 is divided into three independent sub-pixels, emitting red, green, and blue light respectively. Here, the first sub-pixel 101 is designated as the red light sub-pixel, the second sub-pixel 102 as the green light sub-pixel, and the third sub-pixel 103 as the blue light sub-pixel. Combined with... Figure 2 and Figure 3 It can be seen that the spacing between two adjacent nanowire light-emitting structures 12 in the first sub-pixel 101 located in the central region A1 of the nanowire display device is D1, and the spacing between two adjacent nanowire light-emitting structures 12 in the first sub-pixel 101 located in the edge region Ax of the nanowire display device is D11. D1≠D11, therefore, combined with Figure 4 and Figure 5 It can be seen that when the pixel unit 10 in the central region A1 emits light in a vertical direction, the pixel unit 10 in the edge region Ax emits light in a direction deflected by a certain angle relative to the vertical direction. Similarly, the spacing between two adjacent nanowire light-emitting structures 12 in the second sub-pixel 102 located at A1 is D2, and the spacing between two adjacent nanowire light-emitting structures 12 in the second sub-pixel 102 located at Ax is D21, where D2 ≠ D21, so that when the pixel unit 10 in the central region A1 emits light in a vertical direction, the pixel unit 10 in the edge region Ax emits light in a direction deflected by a certain angle relative to the vertical direction. The spacing between two adjacent nanowire light-emitting structures 12 in the third sub-pixel 103 located at A1 is D3, and the spacing between two adjacent nanowire light-emitting structures 12 in the third sub-pixel 103 located at Ax is D31, where D3 ≠ D31, so that when the pixel unit 10 in the central region A1 emits light in the vertical direction, the pixel unit 10 in the edge region Ax emits light in the direction that is deflected at a certain angle relative to the vertical direction.

[0060] Through the above technical solution, this application realizes the control of the light emission angle based on the spacing of the nanowire light-emitting structure 12, so that the emission angle of each pixel unit 10 is synchronously matched with the incident angle requirement of the optomechanical system, and pixel-level light emission angle calibration can be completed without microlenses, thereby improving the display effect of the display screen.

[0061] Combination Figures 1 to 3 As shown, in one embodiment of the present invention, the cross-sectional dimension of the nanowire light-emitting structure 12 in the first sub-pixel 101 is smaller than the cross-sectional dimension of the nanowire light-emitting structure 12 in the second sub-pixel 102, the cross-sectional dimension of the nanowire light-emitting structure 12 in the second sub-pixel 102 is smaller than the cross-sectional dimension of the nanowire light-emitting structure 12 in the third sub-pixel 103, the first sub-pixel 101 is a red light sub-pixel, the second sub-pixel 102 is a green light sub-pixel, and the third sub-pixel 103 is a blue light sub-pixel.

[0062] In this embodiment, the nanowire light-emitting structure 12 is an indium gallium nitride nanowire. Indium gallium nitride nanowires refer to semiconductor nanowire light-emitting structures 12 composed of indium, gallium, and nitrogen elements. Specifically, they can be epitaxially grown on the substrate 20 by metal-organic chemical vapor deposition.

[0063] Specifically, during the growth of indium gallium nitride nanowires, the amount of indium atoms incorporated into the nanowires is related to the crystal growth kinetics. As the nanowire diameter increases, the migration rate of indium atoms adsorbed on the surface accelerates, leading to a decrease in the actual indium content in the active region and thus shortening the emission wavelength. Based on this mechanism, by controlling the diameter of the nanowire light-emitting structures 12 corresponding to the red, green, and blue sub-pixels—for example, using small-diameter nanowires for the red sub-pixels and large-diameter nanowires for the blue sub-pixels—it is possible to simultaneously achieve different emission wavelengths for the first sub-pixel 101, the second sub-pixel 102, and the third sub-pixel 103 under the same process conditions, enabling them to emit red, green, and blue light respectively. This eliminates the need for filters, achieving full-color display and removing the light loss problem caused by filter introduction.

[0064] In one embodiment of the present invention, 170nm≤D1≤690nm, 150nm≤D2≤510nm, and 130nm≤D3≤430nm.

[0065] Wherein, D1 refers to the center-to-center distance between two adjacent nanowire light-emitting structures 12 in the red sub-pixel, D2 refers to the center-to-center distance between two adjacent nanowire light-emitting structures 12 in the green sub-pixel, and D3 refers to the center-to-center distance between two adjacent nanowire light-emitting structures 12 in the blue sub-pixel.

[0066] The arrangement period of the nanowire light-emitting structure 12 affects the resonance effect of light. By controlling the center-to-center spacing of the nanowire light-emitting structure 12 in sub-pixels of different colors within different ranges, the red, green, and blue sub-pixels can resonate. For example, by controlling the D1 of the red sub-pixel between 170nm and 690nm, the red light wave will resonate within this period range, thereby narrowing the emission wavelength range of the spectrum (e.g., from the original 30nm linewidth to 20nm), and also narrowing the emission angle range (e.g., from ±10 degrees to ±5 degrees). Therefore, by controlling the center-to-center spacing of the nanowire light-emitting structure 12 in sub-pixels of different colors within a specific range to induce a resonance effect, stray light interference can be suppressed, and the light can be more concentrated in a certain direction, improving the light emission direction modulation accuracy and display contrast of the nanowire display device.

[0067] In one embodiment of the present invention, the pixel unit 10 includes at least one sub-pixel, and the plurality of nanowire light-emitting structures 12 in the sub-pixel are arranged in a triangular, rectangular or honeycomb array.

[0068] And / or, the shape of the nanowire luminescent structure 12 is cylindrical.

[0069] In this embodiment, a triangular array refers to an array structure in which multiple nanowire light-emitting structures 12 in a sub-pixel are arranged to form a triangular shape. Similarly, a rectangular array refers to an array structure in which multiple nanowire light-emitting structures 12 in a sub-pixel are arranged at intervals along two mutually perpendicular directions and enclosed to form a rectangle. A honeycomb array refers to a hexagonal dot matrix arrangement structure in which multiple nanowire light-emitting structures 12 in a sub-pixel are enclosed.

[0070] For example Figure 7 As shown, each pixel unit includes a sub-pixel, and multiple nanowire light-emitting structures 12 in each sub-pixel are arranged in a rectangular array.

[0071] For example Figure 2 and Figure 3 As shown, each pixel unit includes 3 sub-pixels, and the multiple nanowire light-emitting structures 12 in each sub-pixel are arranged in a rectangular array.

[0072] The nanowire light-emitting structure 12 is shaped like a cylinder. The axial symmetry of the cylindrical structure reduces the anisotropic deviation of the light emission direction, making the light emission of each nanowire light-emitting structure 12 in the same sub-pixel more uniform. This, in turn, makes the spatial gradient characteristics of the light emission angle distribution of each pixel unit 10 more in line with the requirements of the optomechanical system. In other embodiments, the nanowire light-emitting structure 12 can also be a polygonal prism.

[0073] Combination Figure 4 and Figure 5As shown, in one embodiment of the present invention, the nanowire display device further includes a common electrode layer 30, each pixel unit 10 includes at least one sub-pixel, each sub-pixel includes a metal electrode layer 13 and a plurality of nanowire light-emitting structures 12 disposed on the metal electrode layer 13, the metal electrode layer 13 is disposed on the substrate 20, and the common electrode layer 30 is disposed on the side of the nanowire light-emitting structure 12 away from the metal electrode layer 13.

[0074] The nanowire light-emitting structure 12 includes an n-type doped layer 123, a nanowire light-emitting layer 122, and a p-type doped layer 121, which are sequentially stacked between the metal electrode layer 13 and the common electrode layer 30. The p-type doped layer 121 is disposed on the metal electrode layer 30.

[0075] In this embodiment, the metal electrode layer 13 is a conductive metal layer disposed on the substrate 20, which can be formed by depositing conductive materials using sputtering or evaporation processes. The n-type doped layer 123 is a gallium nitride semiconductor thin film formed by doping with pentavalent elements such as phosphorus (P) and arsenic (As), used to provide electron carriers and construct the n-type region of the pn junction. The p-type doped layer 121 is a gallium nitride semiconductor thin film formed by doping with trivalent elements such as boron (B) and aluminum (Al), used to provide hole carriers and construct the p-type region of the pn junction. The nanowire light-emitting layer 122 is an active light-emitting region composed of indium gallium nitride material, used to generate light emission in the visible light band. The common electrode layer 30 is a transparent conductive oxide layer, such as indium tin oxide (ITO), covering the surface of the p-type doped layer 121.

[0076] When an external voltage is applied between the common electrode layer 30 and the metal electrode layer 13, electrons and holes are injected from the n-type doped layer 123 and the p-type doped layer 121 into the nanowire light-emitting layer 122, respectively. They combine within the nanowire light-emitting layer 122 and simultaneously release light energy, emitting light towards the side facing away from the substrate 20. Each sub-pixel is provided with a metal electrode layer 13 to achieve light emission control for different sub-pixels; simultaneously, all pixel units 10 share a common electrode layer 30 to simplify the fabrication process.

[0077] Therefore, this application integrates the light-emitting unit and the light-emitting angle adjustment into the same semiconductor structure, avoiding the optical axis misalignment problem introduced by the microlens assembly process, simplifying the processing technology, and improving the matching accuracy between the nanowire display device and the optomechanical system.

[0078] Combination Figure 4 and Figure 5 As shown, in one embodiment of the present invention, a plurality of nanowire light-emitting structures 12 are arranged at intervals on a substrate 20, and the gaps between adjacent nanowire light-emitting structures 12 are filled with insulating and light-transmitting material to form a planarization layer 11.

[0079] In this embodiment, the insulating and light-transmitting material can be organic or inorganic light-transmitting materials such as silicon oxide, silicon nitride, and polyimide, used to fill the gaps between the nanowire light-emitting structures 12 to reduce light scattering. The insulating and light-transmitting material can be used to cover the gaps between the nanowire light-emitting structures 12 and the side facing away from the substrate 20 through spin coating or chemical vapor deposition processes, forming a continuous planar structure. This not only eliminates the unevenness of the pixel unit 10 surface, but also provides lateral constraint force to the nanowire array through the mechanical strength of the material itself, preventing displacement deviation caused by thermal expansion or external forces, while providing a flat support interface for the upper-layer devices.

[0080] In one embodiment of the present invention, the refractive index difference between the planarization layer 11 and the nanowire light-emitting structure 12 is η, where η ≥ 0.2.

[0081] In this embodiment, when the light emitted by the nanowire light-emitting structure 12 propagates to the interface with the planarization layer 11, the light generates a resonance effect at the interface because the difference in refractive index between the two reaches more than 0.2. The resonance effect can narrow the emission wavelength range of the spectrum, and at the same time, it can also narrow the emission angle range.

[0082] Since the indium content determines the emission wavelength of the nanowire light-emitting structure 12, the wavelength range is fixed for red, green, and blue photonic pixels. By controlling the periodic range of the nanowire light-emitting structure 12 or the refractive index difference between the planarization layer 11 and the nanowire light-emitting structure 12, the display effect and the control precision of the light emission angle can be improved through the resonance effect on the basis of the original light emission.

[0083] In some embodiments, the nanowire light-emitting structure 12 is made of gallium nitride with a refractive index of about 2.4, and the planarization layer 11 is made of silicon dioxide with a refractive index of 1.5, resulting in a refractive index difference of 0.9. In another embodiment, the planarization layer 11 is made of silicon nitride with a refractive index of 1.8, forming a refractive index difference of 0.6 with the gallium nitride nanowire.

[0084] The present invention also proposes a display device, which includes a nanowire display device. The specific structure of the nanowire display device is as described in the above embodiments. Since the present display device adopts all the technical solutions of all the embodiments of the above nanowire display device, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.

[0085] The display device can be an AR, VR, or smart glasses device. The display device integrates nanowire light-emitting structures 12 into pixel units 10, and uses the arrangement of nanowire light-emitting structures 12 to achieve light emission angle adjustment. Since the angle adjustment is directly achieved through the arrangement of the light-emitting structures, it does not rely on external optical components. The optical path matching accuracy is determined by the processing technology of the nanowire light-emitting structures 12, avoiding the angle error caused by microlens assembly deviation, thereby improving the imaging quality and user experience of the display device.

[0086] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention specification and drawings under the technical concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A nanowire display device, characterized in that, The nanowire display device includes a substrate and a plurality of pixel units disposed on the substrate; Each pixel unit includes multiple nanowire light-emitting structures, and the multiple nanowire light-emitting structures of different pixel units are used to emit light of the same or different colors; Along the direction from the center to the edge of the nanowire display device, the nanowire light-emitting structure of each pixel unit is arranged in a periodic variation to adjust the light emission angle of the corresponding area of ​​the nanowire display device.

2. The nanowire display device as described in claim 1, characterized in that, Each pixel unit includes a sub-pixel, and a plurality of nanowire light-emitting structures in the sub-pixel are evenly spaced. Along the direction from the center to the edge of the nanowire display device, the spacing between two adjacent nanowire light-emitting structures in the plurality of pixel units gradually decreases or gradually increases.

3. The nanowire display device as described in claim 1, characterized in that, Each pixel unit includes a first sub-pixel, a second sub-pixel, and a third sub-pixel, wherein the first sub-pixel, the second sub-pixel, and the third sub-pixel each include a plurality of uniformly spaced nanowire light-emitting structures; The spacing between two adjacent nanowire light-emitting structures in the first sub-pixel is D1, the spacing between two adjacent nanowire light-emitting structures in the second sub-pixel is D2, and the spacing between two adjacent nanowire light-emitting structures in the third sub-pixel is D3. Along the direction from the center to the edge of the nanowire display device, D1 in the plurality of pixel units gradually decreases or gradually increases, D2 in the plurality of pixel units gradually decreases or gradually increases, and D3 in the plurality of pixel units gradually decreases or gradually increases.

4. The nanowire display device as described in claim 3, characterized in that, The cross-sectional size of the nanowire light-emitting structure in the first sub-pixel is smaller than that in the second sub-pixel, the cross-sectional size of the nanowire light-emitting structure in the second sub-pixel is smaller than that in the third sub-pixel, the first sub-pixel is a red light sub-pixel, the second sub-pixel is a green light sub-pixel, and the third sub-pixel is a blue light sub-pixel.

5. The nanowire display device as described in claim 3, characterized in that, 170nm≤D1≤690nm, 150nm≤D2≤510nm, 130nm≤D3≤430nm.

6. The nanowire display device according to any one of claims 1 to 5, characterized in that, The pixel unit includes at least one sub-pixel, and the plurality of nanowire light-emitting structures in the sub-pixel are arranged in a triangular, rectangular or honeycomb array. And / or, the shape of the nanowire luminescent structure is cylindrical.

7. The nanowire display device according to any one of claims 1 to 5, characterized in that, The nanowire display device further includes a common electrode layer, each pixel unit includes at least one sub-pixel, each sub-pixel includes a metal electrode layer and a plurality of nanowire light-emitting structures disposed on the metal electrode layer, the metal electrode layer is disposed on the substrate, and the common electrode layer is disposed on the side of the nanowire light-emitting structure away from the metal electrode layer. The nanowire light-emitting structure includes an n-type doped layer, a nanowire light-emitting layer, and a p-type doped layer sequentially stacked between the metal electrode layer and the common electrode layer, wherein the p-type doped layer is disposed on the metal electrode layer.

8. The nanowire display device according to any one of claims 1 to 5, characterized in that, Multiple nanowire light-emitting structures are arranged at intervals on the substrate, and the gaps between adjacent nanowire light-emitting structures are filled with insulating and light-transmitting material to form a planar layer.

9. The nanowire display device as described in claim 8, characterized in that, The refractive index difference between the planarization layer and the nanowire light-emitting structure is η, where η ≥ 0.

2.

10. A display device, characterized in that, The display device includes a nanowire display device as described in any one of claims 1 to 9.

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