MICRO LED display system and manufacturing method thereof

Abstract

The invention provides a Micro LED (Light Emitting Diode) display system. The display system includes: a Micro LED array, which includes a plurality of Micro LEDs; and the super lens array comprises a plurality of super lens units, each super lens unit is provided with at least one super lens, and each super lens unit in the plurality of super lens units is configured to be arranged relative to one corresponding Micro LED in the plurality of Micro LEDs and converges light rays emitted by the corresponding Micro LED to a target position. According to the Micro LED display system provided by the embodiment of the invention, the light rays are converged through the super lens, and the positions of the pixel points can be accurately controlled, so that higher-resolution display is realized.

Description

Technical Field

[0001] This application relates to the field of Micro LED, and more particularly to a Micro LED display system and its manufacturing method. Background Technology

[0002] Micro LED (Micro Light Emitting Diode) is also known as a miniature light-emitting diode. Micro LED display panels feature a high-density integrated LED array, with the distance between LED pixels on the order of micrometers (μm), and each LED pixel is self-emissive. Micro LEDs have been widely used in various display fields; for example, they can serve as pixel units in virtual reality (VR), augmented reality (AR), and mixed reality (MR) displays. Due to the small size of Micro LEDs, even when arranged in an array, their display area may still be relatively small. Therefore, Micro LED displays sometimes need to be used in conjunction with magnifying lenses to expand the relative positions between the imaging pixels, thus presenting a magnified image to the user.

[0003] In addition, Micro LEDs can also be used in printing and other fields. Micro LED printers form a latent image by shining light carrying image signals onto a photosensitive drum. After absorbing toner, the latent image is transferred to the printing paper and fixed. In this process, optical devices such as rod lenses are used to converge the divergent light emitted by the Micro LEDs and shine the converged light onto predetermined positions on the photosensitive drum to complete the pixel imaging.

[0004] However, optical devices such as magnifying lenses and rod lenses are not small compared to miniaturized electronic components, and they require a corresponding optical path to achieve their optical functions. Arranging large optical path structures within already cramped electronic devices contradicts the goal of miniaturizing electronic devices.

[0005] Therefore, it is necessary to propose an improved optical structure for Micro LED display systems. Summary of the Invention

[0006] To address one or more of the aforementioned technical problems, this application provides a Micro LED display system and its manufacturing method. In this system, a superlens is used to replace a traditional lens to focus light, enabling precise control of pixel positions and thus achieving higher resolution display.

[0007] Some embodiments of this application provide a Micro LED display system, comprising: a Micro LED array including a plurality of Micro LEDs; and a superlens array including a plurality of superlens units, wherein each of the plurality of superlens units has at least one superlens, wherein the Micro LEDs among the plurality of Micro LEDs have a corresponding superlens unit in the plurality of superlens units, and the corresponding superlens unit is capable of focusing the light emitted by the Micro LED to a target location.

[0008] Some embodiments of this application provide a method for manufacturing a Micro LED display system, comprising the following steps: forming a Micro LED array including a plurality of Micro LEDs; forming a superlens array including a plurality of superlens units, wherein each of the plurality of superlens units has at least one superlens; arranging each of the plurality of superlens units relative to a corresponding Micro LED among the plurality of Micro LEDs to form the Micro LED display system, wherein the corresponding superlens unit is capable of focusing the light emitted by the Micro LED to a target location.

[0009] The Micro LED display system and manufacturing method according to some embodiments of this application can shorten the optical path length required to achieve optical convergence by utilizing the fine microstructure of a superlens, thereby facilitating the miniaturization of the Micro LED display system. On the other hand, the fine microstructure of the superlens enables more precise light focusing than conventional methods, thus ensuring pixel display quality. It should be noted that the embodiments of this application do not necessarily require complete realization of the above-described technical effects, and the technical effects achieved by solving at least one technical problem constitute a contribution to the prior art. Attached Figure Description

[0010] The above and other objects, features and advantages of this disclosure will become more apparent from the more detailed description of exemplary embodiments thereof taken in conjunction with the accompanying drawings, wherein like reference numerals generally denote like parts.

[0011] Figure 1 This illustrates a prior art Micro LED display system;

[0012] Figure 2 A schematic diagram showing the relationship between the refractive index and radius of a rod-shaped lens is provided.

[0013] Figure 3 The display effect of the rod lens is shown;

[0014] Figure 4 A cross-sectional view of a superlens according to some embodiments of this application is shown;

[0015] Figure 5 A top view of a superlens according to some embodiments of this application is shown;

[0016] Figure 6 A perspective view of a single nanopillar of a superlens according to some embodiments of this application is shown;

[0017] Figure 7 A Micro LED display system according to some embodiments of this application is shown;

[0018] Figure 8 A display system combining Micro LED and superlens according to some embodiments of this application is shown;

[0019] Figure 9 A Micro LED display system according to some embodiments of this application is shown;

[0020] Figure 10 A Micro LED display system according to some embodiments of this application is shown;

[0021] Figure 11 A display system combining Micro LED and superlens according to some embodiments of this application is shown;

[0022] Figure 12 A Micro LED display system according to some embodiments of this application is shown;

[0023] Figure 13 A method for manufacturing a Micro LED display system according to some embodiments of this application is illustrated. Detailed Implementation

[0024] Preferred embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While preferred embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the present disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0025] Figure 1A Micro LED display system 10 according to some embodiments of this application is illustrated. Specifically, the Micro LED display system 10 is a Micro LED printer including a Micro LED array 110, a rod lens array 120, and a photosensitive drum 103. It should be understood that the components illustrated are shown to illustrate the main working principle of the Micro LED printer, and the Micro LED display system 10 also includes other components (e.g., a power supply system, a processing unit for processing graphic data, a communication unit, etc.), which will not be described in detail here.

[0026] like Figure 1 As shown, the Micro LED array 110 includes Micro LEDs 101 arranged in a row. During a single illumination, a row of Micro LEDs 101 can form a latent image of a graphic layout on the photosensitive drum 103. As the photosensitive drum 103 rolls in the illustrated direction, the row of Micro LEDs 101, illuminated multiple times, can form a full-area latent image of a graphic layout on the photosensitive drum 103. The rod lens array 120 of the Micro LED display system 10 includes a plurality of rod lenses 102. For example, two rows of staggered rod lenses 102 can be used to form the rod lens array 120. The row of Micro LEDs 101 can be positioned at the center corresponding to the two rows of staggered rod lenses 102. The distance between the rod lens array 120 and the Micro LEDs 101 can be equal to the distance between the rod lens array 102 and the photosensitive drum 103. In this way, each MicroLED 101 can form a normal, same-size image on the photosensitive drum 103 through the rod lens 102.

[0027] As can be seen, the Micro LED display system 10 can image the image by passing light carrying image signals through the Micro LEDs 101 in the Micro LED array 110, and then focus the light through the bar lenses 102 in the bar lens array 120, converging the divergent light emitted by the Micro LEDs 101 to illuminate the target position on the photosensitive drum 103, thereby forming a latent image on the photosensitive drum 103. Subsequently, the latent image absorbs toner and is transferred to printing paper for fixing.

[0028] Because the optical focusing of the rod lens 102 needs to maintain its size, the volume of the Micro LED display system 10, which uses a rod lens array 120 comprising several rod lenses 102 for light focusing, cannot be further reduced. On the other hand, the rod lens 102 is a refractive lens, and due to optical distortion, its imaging accuracy is generally not high. This will lead to spherical aberration optical problems during imaging, potentially forming diffuse spots near the target position on the photosensitive drum 103, thus affecting the typesetting quality.

[0029] Figure 2 A schematic diagram illustrating the refractive index versus radius of a single rod-shaped lens 102 according to some embodiments of this application is shown. Figure 2 As shown, the refractive index of the rod lens 102 is highest along its axis. For example, with Figure 2 The cross-section of the rod-shaped lens 102 shown is the subject of study; the cross-section can be a standard circle. For simplicity, Figure 2 The distribution of the refractive index of the rod lens 102 across a cross section is illustrated using the bottom surface of the rod lens 102 as an example. It should be understood that the refractive index relationship shown in the figure also applies to other cross sections of the rod lens 102, thus forming the optical characteristics of the rod lens 102. As shown, the refractive index is highest at the center o and gradually decreases along the radius r from the center o, enabling continuous refraction of axially propagating light. Therefore, the rod lens 102 is also called a gradient refractive index rod lens.

[0030] It should be noted that, Figure 2 The refractive index versus radius relationship shown is under ideal conditions. However, due to limitations in material purity and manufacturing process errors, the actual manufactured rod lens 102 cannot perfectly match the ideal shape. Figure 2 The relationship presented in the text.

[0031] Figure 3 The display effect of a single rod-shaped lens 102 according to some embodiments of this application is shown. For example... Figure 3As shown, in this example, the Micro LED 101 is positioned below the optical axis l of the rod lens 102, with a distance of approximately 2.5 mm from one end of the rod lens 102 (i.e., object distance L0). The diameter D of the rod lens 102 is approximately 0.45 mm and its length Z is approximately 4.3 mm. The screen used to observe the real image after passing through the rod lens 102 (e.g., a whiteboard) is also approximately 2.5 mm from the other end of the lens 102 (i.e., image distance L1). Representative rays a, b, c, and d emitted by the Micro LED 101 are refracted by the rod lens 102, and their paths within the rod lens 102 are shown in the figure, ultimately converging on the screen. For ease of processing, the Micro LED 101 is considered here as an idealized point light source, and rays a, b, c, and d are four representative rays emitted by the point light source Micro LED 101 in all directions. However, due to the various defects described above that may exist in the rod lens 102, after being converged by the rod lens 102, light rays a, b, c, and d cannot converge to a single point on the screen, and may exhibit the following characteristics: Figure 3 The diffused light spot pattern is shown on the right. In other words, the point light source Micro LED 101, focused onto the screen by the rod lens 102, forms a radiating pattern with a halo effect centered on a single point. Although most of the energy of the point light source Micro LED 101 is concentrated in the central region, the halo outside the central region will affect the imaging effect. If a Micro LED array composed of multiple Micro LEDs 101 is used for imaging on the screen, the images of each Micro LED 101 on the screen may overlap. For the observer on the screen, the image presented by the Micro LED array on the screen is blurry, and the image resolution is therefore low. On the other hand, as... Figure 3 As shown, light needs to be flipped twice to display an image, for example, an upright and life-size image, on the screen. Therefore, the length of the rod lens 102 is difficult to further reduce. It should be noted that the screen here can be a photosensitive drum in a practical display system, or it can be a medium such as semi-reflective glass.

[0032] Some embodiments of this application will replace traditional optical devices such as rod lenses with superlenses and apply them to display systems. Figures 4-6A superlens according to some embodiments of this application is illustrated. The superlens has a two-dimensional planar lens structure and can be made from an optical element that focuses light using a metasurface (a planar two-dimensional metamaterial with subwavelength thickness). Compared to conventional lenses, superlenses offer advantages such as thinner size, lighter weight, lower cost, better imaging, and easier integration, providing a potential solution for compact, integrated optical systems. Furthermore, the polarization, phase, and amplitude of light can be controlled by adjusting parameters such as the shape, rotation direction, and height of the structure.

[0033] like Figures 4 to 6 As shown, the superlens may include transparent optical glass layers 401 and 402, nanopillars 403, and filler material 404. In some examples, for a superlens with a flat SiO2 surface (e.g., SiO2 as filler material 404 with a flat surface), a transparent optical glass layer 401 may no longer be covered on its surface. Instead, the optical coupling can be achieved by aligning and bonding the SiO2 surface of the superlens with the display pixel Micro LED. The nanopillars 403 may be made of the dielectric material TiO2 or Si3N4, because the transmittance of visible light in TiO2 or Si3N4 is greater than 80%. Due to the high refractive index of TiO2 and Si3N4, their extinction coefficient for visible light is almost 0. The radius, thickness, arrangement, and other technical specifications of the nanopillars 403 can be set as needed to achieve the specific optical performance of the superlens. Furthermore, the filler material 404 is a transparent or translucent filler material with an absolute value of refractive index difference greater than or equal to 0.5 with the nanostructure; for example, it may be SiO2.

[0034] Some embodiments of this application provide a Micro LED display system. Figure 7 A Micro LED display system 70 (hereinafter referred to as display system 70) according to some embodiments of this application is illustrated. Specifically, display system 70 may be a Micro LED printer. Figure 7 As shown, the display system 70 includes a Micro LED array 710 and a superlens array 720. The Micro LED array 710 includes multiple Micro LEDs 701. Specifically, the Micro LED array 710 includes Micro LEDs 701 arranged in a row. As the photosensitive drum 103 rolls in the direction shown, a row of Micro LEDs 701 can form a full-width latent image of text and image layout on the photosensitive drum 103. It can be understood that... Figure 7 For illustrative purposes, only one row of four Micro LED 701s is shown. Depending on the requirements for developing and printing speeds, the number of rows of Micro LED 701s can be increased. For example, Figure 7The Micro LED 701 shown can be extended in the horizontal direction and in the vertical direction perpendicular to the paper to form a complete Micro LED array 710.

[0035] Furthermore, the superlens array 720 includes multiple superlens units 721. Each superlens unit 721 has at least one superlens. For example, the superlens unit 721 can be composed of one or more superlenses arranged in a specific manner. The superlens unit 721 can be used to converge the light emitted by the Micro LED 701 in the Micro LED array 710, thereby forming a latent image on the photosensitive drum 103. Compared to conventional rod lenses, superlenses can achieve a larger angle of light deflection, and aberration correction allows the light to be precisely focused at a single point.

[0036] In some embodiments, each Micro LED 701 in the Micro LED array 710 has a corresponding superlens unit 721, and the corresponding superlens unit 721 can focus the light emitted by the Micro LED 701 onto the target location, thereby forming a latent image at a specified location on the photosensitive drum 103. Figure 7 As shown, the number of Micro LEDs 701 in the Micro LED array 710 is equal to the number of superlens units 721 in the superlens array 720. A superlens unit 721 may contain one or more superlenses, and each superlens unit 721 is arranged relative to a corresponding Micro LED 701 (e.g., a Micro LED 701 is bonded to a superlens of the superlens unit 721). Similar to the Micro LEDs 701, the superlens units 721 can also be extended laterally and vertically perpendicular to the plane of the paper to form a complete superlens array 720.

[0037] Continue to refer to Figure 7 The superlens unit 721 may include a pair of parallel-arranged first superlens 722 and second superlens 723. The Micro LED 701 and the first superlens 722 are bonded together. Figure 7 The diagram also illustrates several exemplary light rays 730 emitted from the Micro LED 701 and reaching the photosensitive drum 103. The light rays 730 are emitted from the point light source Micro LED 701 and reach a first superlens 722. The first superlens 722 processes the light rays 730 to make them parallel beams. The parallel beams then reach a second superlens 723, which converges them, ultimately focusing the light rays 730 onto a single point. Thus, the parallel arrangement of the first superlens 722 and the second superlens 723 achieves the convergence of light rays emitted from the point light source Micro LED 701, enabling the formation of a latent image at a target location on the photosensitive drum 103.

[0038] To ensure that the light 730 converges at the target position on the photosensitive drum 103 along a predetermined optical path, the first superlens 722 and the second superlens 723 can be designed according to predetermined parameter specifications, and the positional relationship of each optical component also needs to meet certain conditions. Specifically, the distance from the first superlens 722 of the superlens unit 721 to the light-emitting layer of the Micro LED 701 corresponding to the superlens unit 721 is equal to the focal length of the first superlens 722, and the distance from the second superlens 723 of the superlens unit 721 to the target position on the photosensitive drum 103 is equal to the focal length of the second superlens 723. In some embodiments, the focal length of the first superlens 722 can be equal to the focal length of the second superlens 723. That is, to simplify the design, the first superlens 722 and the second superlens 723 can have the same technical specifications.

[0039] In some embodiments, the thicknesses of the first superlens 722 and the second superlens 723 are between 0.4 mm and 0.6 mm. For example, the thicknesses of the first superlens 722 and the second superlens 723 can be 0.5 mm. Depending on the size of the Micro LED, the distance from the first superlens 722 of the superlens unit 721 to the light-emitting layer of the Micro LED 701 corresponding to the superlens unit 721 can be between 1 μm and 10 mm, for example, approximately 2.5 μm (i.e., the focal length of the first superlens 722). The light-gathering ratio of the first superlens 722 will decrease as the distance from the first superlens 722 to the light-emitting layer of the Micro LED 701 increases; therefore, to ensure imaging quality, the distance from the first superlens 722 to the light-emitting layer of the Micro LED 701 should not be too long. The distance from the second superlens 723 of the superlens unit 721 to the target position on the photosensitive drum 103 can also be 2.5 μm (i.e., the focal length of the second superlens 723). It is understandable that the focal length of the second superlens 723 can be specially designed according to the required imaging distance. Since the light rays 730 of the first superlens 722 and the second superlens 723 are parallel, the distance between the first superlens 722 and the second superlens 723 can be varied. That is, the first superlens 722 and the second superlens 723 can be moved in a translational manner.

[0040] In some embodiments, the first superlens 722 and the second superlens 723 are both square lenses with the same technical specifications, and a point (x, y) on them is configured to satisfy the following phase relationship:

[0041]

[0042] Where x and y are the coordinates of the point with the center of the first superlens 722 (second superlens 723) as the origin.

[0043] The x and y coordinates of the point. f is the focal length of the first superlens 722 (second superlens 723). Let be the phase of the ray at point (x, y). Specifically, This refers to the phase change of light ray 730 before and after passing through point (x, y). In practical applications, various phase modulation methods can be used to achieve the desired functions and effects when fabricating superlenses. The main phase control methods between operations include resonant phase modulation, propagation phase modulation, and geometric phase modulation (also known as Pancharatnam-Berry phase modulation). Furthermore, in the above formula, λ represents the wavelength of light 730 emitted by the Micro LED 701 corresponding to the superlens unit 721 of the first superlens 722 and the second superlens 723.

[0044] Figure 8 A display system 80 according to some embodiments of this application is illustrated. The display system 80 includes a Micro LED 701 and a superlens unit 721. In this embodiment, the superlens unit 721 includes a first superlens 722 and a second superlens 723. It should be understood that the display system 80 can be a partial close-up of the display system 70, and the following description of the display system 80 is applicable to the display system 70. Figure 8 As shown, the display system 80 also includes a transparent filler layer 711, which is located on the substrate 801 of the Micro LED 701 and fills the area around the light-emitting mesa 802 of the Micro LED 701. The transparent filler layer 711 further fills the space between the Micro LED 701 and the first superlens 722, and the distance between the light-emitting layer of the Micro LED 701 and the first superlens 722 can be set by changing the thickness of the transparent filler layer 711. The first superlens 722 of the superlens unit 721 corresponding to the Micro LED 701 can be bonded to the transparent filler layer 711. The structure of the Micro LED 701 and its substrate 801, light-emitting mesa 802, and other components can be referred to Micro LED related technologies, and will not be described in detail here.

[0045] return Figure 7In the display system 70, each Micro LED 701 can be arranged on the same plane, and a gap 712 exists between the transparent filler layers 711 of adjacent Micro LEDs 701. The gap 712 between two adjacent Micro LEDs 701 separates them, and its cross-section can present a triangular structure that is narrower at the top and wider at the bottom. Due to the existence of the gap 712, the light 730 emitted by two adjacent Micro LEDs 701 will not have crosstalk before reaching the first superlens 722, thus ensuring the purity of the light 730 entering the first superlens 722. That is, the light 730 entering the corresponding first superlens 722 comes from only one Micro LED 701.

[0046] Continue to refer to Figure 7 The first superlens 722 in each superlens unit 721 can be arranged on the same plane, and the display system 70 also includes a light-absorbing layer arranged between the first superlens 722 of two adjacent superlens units 721. Figure 8 The magnified view shows the light-absorbing layer 824 disposed between adjacent first superlenses 722. The light-absorbing layer 824 between two adjacent first superlenses 722 absorbs the light 730 emitted by their respective Micro LEDs 701 that reaches the edge of the first superlens 722, thereby preventing it from entering the adjacent first superlenses 722 and further affecting the subsequent display effect. The light-absorbing layer 824 can be a gel-like material and is formed between two adjacent first superlenses 722 by deposition or coating. In some embodiments, the height of the light-absorbing layer 824 can be the same as the height of the nanopillars of the first superlenses 722.

[0047] Figure 9 A Micro LED display system 90 (hereinafter referred to as display system 90) according to some embodiments of this application is illustrated. Specifically, display system 90 may be a Micro LED head-mounted display system (e.g., an AR display). Figure 7Similar to the display system 70 shown, the display system 90 also includes a Micro LED array and a superlens array. The Micro LED array can include multiple Micro LEDs arranged in rows and columns. For example, for the display system 90 with a resolution of 640×480, the Micro LED array can be composed of 640 rows × 480 columns of Micro LEDs. Correspondingly, the superlens array can also be composed of 640 rows × 480 columns of superlens units, with each superlens unit corresponding to one Micro LED. Unlike the display system 70, the image processed by the superlens array will not form a latent image on the photosensitive drum, but will be projected onto a medium such as a semi-reflective glass 903, presenting a real image to the user.

[0048] The above embodiments describe the use of a set of parallel superlenses to converge light. Thanks to the fine structure of the superlenses, the light converging effect is significantly better than conventional methods. Some embodiments of this application provide a Micro LED display system that can further reduce the size of the display system.

[0049] Figure 10 A Micro LED display system 1000 according to some embodiments of this application is shown. For example... Figure 10 As shown, similar to Figure 7 The display system 70 and display system 1000 shown include a Micro LED array 710 and a superlens array 720. The Micro LED array 710 includes multiple Micro LEDs 701. Specifically, the Micro LED array 710 includes Micro LEDs 701 arranged in a row. As the photosensitive drum 103 rolls in the direction shown, a row of Micro LEDs 701 can form a full-width latent image of text and image layout on the photosensitive drum 103. Figure 7 For illustrative purposes, only four MicroLEDs 701 are shown in a row. The MicroLEDs 701 can be extended horizontally and vertically perpendicular to the paper to form a complete MicroLED array 710.

[0050] Furthermore, the superlens array 720 includes multiple superlens units 721, and each superlens unit 721 consists of only one superlens 1001. The superlens 1001 can be used to converge the light emitted by the Micro LEDs 701 in the Micro LED array 710, thereby forming a latent image on the photosensitive drum 103. In some embodiments, each Micro LED 701 in the Micro LED array 710 has a corresponding superlens 1001, and the corresponding superlens 1001 can converge the light emitted by the Micro LED 701 to a target location, thereby achieving the formation of a latent image at a designated location on the photosensitive drum 103. Figure 10 As shown, the number of Micro LEDs 701 in the Micro LED array 710 is equal to the number of superlenses 1001, and each superlens 1001 is arranged relative to a corresponding Micro LED 701 (e.g., each superlens 1001 is bonded to each micro LED 701). Similar to the Micro LEDs 701, the superlens units 721 can also be extended in the transverse direction and the longitudinal direction perpendicular to the plane of the paper to form a complete superlens array 720.

[0051] In order for the light 730 to converge at the target position on the photosensitive drum 103 along a predetermined optical path, the superlens 1001 can be designed according to predetermined parameter specifications, and the positional relationship of each optical component also needs to meet certain conditions. Specifically, the distance from the superlens 1001 to the light-emitting layer of the corresponding Micro LED 701 is equal to twice the focal length of the superlens 1001.

[0052] In some embodiments, the thickness of the superlens 1001 is between 0.4 mm and 0.6 mm. For example, it can be 0.5 mm. The distance from the superlens 1001 to the light-emitting layer of its corresponding Micro LED 701 is approximately 2.5 μm (i.e., twice the focal length of the superlens 1001). The distance from the superlens 1001 to the target position on the photosensitive drum 103 can be specifically controlled by designing the microstructure of the superlens 1001.

[0053] In some embodiments, the superlens 1001 is a square lens, and a point (x, y) on it is configured to satisfy the following phase relationship:

[0054]

[0055] Where x and y are the abscissa and ordinate of the point with the center of the superlens 1001 as the origin, respectively. f is the focal length of the superlens 1001, and n is the ratio of the image distance to the focal length. Let be the phase of the ray at point (x, y). Specifically, This refers to the phase change of light ray 730 before and after passing through point (x, y). λ is the wavelength of light ray 730 emitted by Micro LED 701 corresponding to superlens 1001.

[0056] Figure 11 A display system 1100 combining a Micro LED 701 with a superlens 1001 according to some embodiments of this application is shown. It should be understood that the display system 1100 can be a partial close-up of the display system 1000, and the following description of the display system 1100 is applicable to the display system 1000. Figure 11 As shown, the display system 1100 includes a transparent filler layer 711 located above the substrate 801 of the Micro LED 701 and filling around the light-emitting mesa 802 of the Micro LED 701. The transparent filler layer 711 further fills the space between the Micro LED 701 and the superlens 1001. The distance between the light-emitting layer of the Micro LED 701 and the superlens 1001 can be set by changing the thickness of the transparent filler layer 711. The superlens 1001 corresponding to the Micro LED 701 is disposed above the transparent filler layer 711.

[0057] Combination Figure 10 In the display system 1000, each Micro LED 701 can be arranged on the same plane, and a gap 712 exists between the transparent filling layers 711 of adjacent Micro LEDs 701. The gap 712 between two adjacent Micro LEDs 701 separates them, and its cross-section can present a triangular structure that is narrower at the top and wider at the bottom. Due to the existence of the gap 712, the light 730 emitted by two adjacent Micro LEDs 701 will not have crosstalk when it reaches the superlens 1001, thus ensuring the purity of the light 730 entering the superlens 1001. That is, the light 730 entering the corresponding superlens 1001 comes from only one Micro LED 701.

[0058] Continue to refer to Figure 10 The superlenses 1001 can be arranged on the same plane, and the display system 1000 also includes light-absorbing layers arranged between adjacent superlenses. Figure 11The magnified view shows the light-absorbing layer 1101 disposed between adjacent superlenses 1001. The light-absorbing layer 1101 between two adjacent superlenses 1001 absorbs the light 730 emitted by their respective MicroLEDs 701 that reaches the edge of the superlens 1001, thereby preventing it from entering the adjacent superlenses 1001 and further affecting the subsequent display effect. The light-absorbing layer 1101 can be a gel-like material and is formed between two adjacent superlenses 1001 by deposition or coating.

[0059] Figure 12 A Micro LED display system 1200 (hereinafter referred to as display system 1200) according to some embodiments of this application is illustrated. Specifically, display system 1200 may be a Micro LED head-mounted display system (e.g., an AR display). Figure 10 Similar to the display system 1000 shown, the display system 1200 also includes a Micro LED array and a superlens array. The Micro LED array can include multiple Micro LEDs arranged in rows and columns. For example, for the display system 90 with a resolution of 640×480, the Micro LED array can be composed of 640 rows × 480 columns of Micro LEDs. Correspondingly, the superlens array can also be composed of 640 rows × 480 columns of superlenses, with each superlens corresponding to a Micro LED. Unlike the display system 1000, the image processed by the superlens array will not form a latent image on the photosensitive drum, but will be projected onto a medium such as a semi-reflective glass 1203, presenting a real image to the user.

[0060] Some embodiments of this application provide a method for manufacturing a Micro LED display system. Figure 13 A method 1300 for manufacturing a Micro LED display system according to some embodiments of this application is shown, such as... Figure 13 As shown, method 1300 includes the following steps 1302 to 1306.

[0061] In step 1302, a Micro LED array comprising multiple Micro LEDs is formed. The Micro LED array formed in step 1302 may include the features described above regarding Micro LED arrays in Micro LED display systems, and the relevant content is incorporated herein by reference, and will not be repeated here.

[0062] In step 1304, a superlens array comprising a plurality of superlens units is formed, wherein each of the plurality of superlens units has at least one superlens. The superlens array formed in step 1304 may include the features described above regarding superlens arrays in Micro LED display systems, the relevant content of which is incorporated herein by reference and will not be repeated here.

[0063] In step 1306, each of the plurality of superlens units is arranged relative to a corresponding Micro LED among the plurality of Micro LEDs to form the Micro LED display system. The corresponding superlens unit can focus the light emitted by the Micro LED onto the target location. In some examples of this application, the superlens unit and the corresponding Micro LED are coupled together by bonding. It is understood that the superlens array formed in step 1306 may include the features described above regarding the Micro LED display system, and the relevant content is incorporated herein by reference, and will not be repeated here.

[0064] It should be noted that relational terms in this document, such as “first” and “second”, are used only to distinguish an entity or operation from another entity or operation, without requiring or implying any actual relationship or order between these entities or operations. Furthermore, the words “including,” “having,” and “containing,” as well as other similar forms, are intended to be equivalent in meaning and are open-ended; one or more items following any of these words do not imply an exhaustive list of such items or that the list is limited to only one or more items.

[0065] As used herein, unless expressly stated otherwise, the term "or" covers all possible combinations unless impractical. For example, if a component is stated to include A or B, then unless expressly stated otherwise or impractical, the component may include A, or B, or A and B. As a second example, if a component is stated to include A, B, or C, then unless expressly stated otherwise or impractical, the component may include A, or B, or C, or A and B, or A and C, or B and C, or A and B and C.

[0066] In the foregoing description, numerous specific details have been described, which may vary depending on the implementation. Certain modifications and alterations may be made to the described embodiments. Other embodiments will be apparent to those skilled in the art in light of the specification and practice of this application disclosed herein. The specification and examples are intended to be considered exemplary only, and the true scope and spirit of this application are indicated by the following claims. The sequence of steps shown in the accompanying drawings is also intended for illustrative purposes only and is not intended to limit one to any particular order of steps. Therefore, those skilled in the art will understand that these steps may be performed in different orders while achieving the same method.

[0067] Exemplary embodiments have been disclosed in the accompanying drawings and description. However, many variations and modifications can be made to these embodiments. Therefore, although specific terminology has been used, it is used in a general and descriptive sense only and not for limiting purposes.

Claims

1. A Micro LED display system, characterized in that, The display system includes: Micro LED array, comprising multiple Micro LEDs; and A superlens array comprising a plurality of superlens units, wherein each of the plurality of superlens units has at least one superlens. Each of the plurality of superlens units corresponds to one of the plurality of Micro LEDs, and the superlens unit is capable of focusing the light emitted by the corresponding Micro LED onto the target location.

2. The display system according to claim 1, characterized in that, At least one of the superlens units includes a pair of parallel-arranged first superlenses and second superlenses, wherein the distance from the first superlens to the light-emitting layer of the Micro LED corresponding to the superlens unit is equal to the focal length of the first superlens, and the distance from the second superlens to the target position is equal to the focal length of the second superlens.

3. The display system according to claim 2, characterized in that, The focal length of the first superlens is equal to the focal length of the second superlens.

4. The display system according to claim 2, characterized in that, The first and second superlenses are square lenses, and a point (x, y) on the first and second superlenses is configured to satisfy the following phase relationship: Where x and y are the abscissa and ordinate of the point with the center of the first or second superlens as the origin, respectively, and f is the focal length of the first or second superlens. Let λ be the phase of the light ray at point (x, y), and λ be the wavelength of the light emitted by the corresponding Micro LED.

5. The display system according to claim 2, characterized in that, The display system further includes a transparent filler layer that fills the substrate of the Micro LED and the area around the light-emitting platform of the Micro LED, with a first superlens corresponding to the Micro LED disposed on the transparent filler layer.

6. The display system according to claim 5, characterized in that, The plurality of Micro LEDs are arranged on the same plane, and there are gaps between the transparent filler layers in adjacent Micro LEDs.

7. The display system according to claim 2, characterized in that, The first superlenses in the plurality of superlens units are arranged on the same plane, and the display system further includes a light-absorbing layer arranged between the first superlenses of adjacent superlens units.

8. The display system according to claim 1, characterized in that, The superlens unit includes a superlens, wherein the distance from the superlens to the corresponding light-emitting layer of the Micro LED is equal to twice the focal length of the superlens.

9. The display system according to claim 8, characterized in that, The superlens is a square lens, and a point (x, y) on the superlens is configured to satisfy the following phase relationship: Where x and y are the abscissa and ordinate of the point with the center of the superlens as the origin, respectively, f is the focal length of the superlens, and n is the ratio of image distance to focal length. Let λ be the phase of the light ray at point (x, y), and λ be the wavelength of the light emitted by the corresponding Micro LED.

10. The display system according to claim 8, characterized in that, The display system further includes a transparent filler layer that fills the substrate of the Micro LED and the area around the light-emitting platform of the Micro LED, and the superlens corresponding to the Micro LED is arranged on the transparent filler layer.

11. The display system according to claim 10, characterized in that, The plurality of Micro LEDs are arranged on the same plane, and there are gaps between the transparent filler layers in adjacent Micro LEDs.

12. The display system according to claim 8, characterized in that, The superlenses are arranged on the same plane, and the display system further includes a light-absorbing layer arranged between adjacent superlenses.

13. The display system according to claim 1, characterized in that, The thickness of the at least one superlens is between 0.4 mm and 0.6 mm.

14. The display system according to claim 1, characterized in that, The thickness of the at least one superlens is 0.5 mm.

15. The display system according to claim 1, characterized in that, The focal length of the at least one superlens is between 1 μm and 10 mm.

16. The display system according to claim 1, characterized in that, The focal length of the at least one superlens is 2.5 μm.

17. The display system according to claim 1, characterized in that, The display system also includes a photosensitive drum, and the target position is located on the photosensitive drum.

18. The display system according to claim 1, characterized in that, The target location is situated on an optically reflective medium.

19. A method for manufacturing a Micro LED display system, characterized in that, The method includes: Forming a Micro LED array comprising multiple Micro LEDs; Forming a superlens array comprising a plurality of superlens units, wherein each of the plurality of superlens units has at least one superlens; and The micro LED display system is formed by arranging each of the plurality of microlens units relative to one of the plurality of micro LEDs, wherein the corresponding microlens unit is capable of focusing the light emitted by the micro LED onto the target location.

20. The method according to claim 19, characterized in that, The superlens unit is coupled to the corresponding Micro LED by bonding.

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