Aerial imaging device, aerial imaging system and vehicle

Abstract

The invention discloses an aerial imaging device, an aerial imaging system and a vehicle, and the device comprises an optical waveguide unit which is provided with a curved surface structure, and the optical waveguide unit is used for converging received image light in the air through the curved surface structure to form a real image. According to the invention, a diffraction optical waveguide aerial imaging scheme is adopted, a curved surface structure is introduced into the optical waveguide unit, the propagation path of light is adjusted, and image light is converged in the air to form a real image, so that the breakthrough of a system structure from a stereo to a plane is realized, the volume, weight and the like of an aerial imaging system are greatly reduced, and the aerial imaging system can be more conveniently arranged at each position of a vehicle.

Description

Technical Field

[0001] This application relates to the field of display technology, and more specifically, to an aerial imaging device, an aerial imaging system, and a vehicle. Background Technology

[0002] With the increasing number of cars on the road, the in-cabin experience, as a third space besides living and working, is becoming increasingly important. In the smart cockpit of a car, aerial imaging technology can replace the traditional center console display, projecting navigation information, entertainment content, and other content directly in front of the driver. However, aerial imaging display solutions suffer from problems such as large system size and heavy weight. Summary of the Invention

[0003] This application provides an aerial imaging device, an aerial imaging system, and a vehicle. The size and weight of the aerial imaging system are reduced.

[0004] To achieve the above objectives, according to a first aspect of this application, an aerial imaging device is provided, comprising:

[0005] An optical waveguide unit having a curved surface structure is used to converge received image light rays in the air through the curved surface structure to form a real image.

[0006] Optionally, the curved structure is disposed on the side of the optical waveguide unit facing the real image.

[0007] Optionally, the curvature of the surface structure is inversely correlated with the size of the real image.

[0008] Optionally, the curvature of the surface structure is inversely correlated with the distance between the real image and the optical waveguide unit.

[0009] Optionally, the optical waveguide unit includes a coupling element, a waveguide substrate, and a coupling element.

[0010] The coupling element is used to couple the image light into the waveguide substrate;

[0011] The waveguide substrate is used to transmit the image light;

[0012] The coupling element is used to couple out the image light.

[0013] Optionally, the waveguide substrate is used to transmit and modulate the image light, and the first surface of the waveguide substrate facing the real image is concave.

[0014] The coupling element is used to couple the image light rays out and converge them in the air to form the real image.

[0015] Optionally, the second surface of the waveguide substrate facing away from the real image is a convex surface, and the concave surface and the convex surface have the same curvature.

[0016] Optionally, the optical waveguide unit further includes a convex lens.

[0017] The coupling element is used to couple the image light rays to the convex lens;

[0018] The convex lens is used to converge the image light rays in the air to form the real image.

[0019] Optionally, the third surface of the convex lens on the side facing the real image is convex.

[0020] Optionally, the coupling element and the coupling element are surface relief gratings or volume holographic gratings.

[0021] Optionally, the coupling diffraction efficiency of the coupling element gradually increases along the direction of image light transmission.

[0022] Optionally, the coupling element is a one-dimensional grating or a two-dimensional grating.

[0023] Optionally, the optical waveguide unit further includes a transition element, wherein the coupling element is a one-dimensional grating.

[0024] The deflection element is used to redirect the image light transmitted from the waveguide substrate and transmit it to the coupling element, thereby expanding the pupil of the image light.

[0025] According to a second aspect of this application, an aerial imaging system is provided, comprising:

[0026] A micro-projection optical engine, wherein the micro-projection optical engine is used to output image light; and

[0027] The aforementioned aerial imaging device is used to converge the image light rays in the air to form a real image.

[0028] Optionally, the micro-projection optical engine includes a microdisplay and a collimator.

[0029] The microdisplay is used to output the image light;

[0030] The collimator is used to convert the image light into a multi-field collimated parallel beam.

[0031] According to a third aspect of this application, a vehicle is provided that includes the aerial imaging system as described above.

[0032] This application adopts a diffractive waveguide aerial imaging scheme. By introducing a curved structure into the waveguide unit, the propagation path of light is adjusted, and the image light rays are converged in the air to form a real image. This achieves a breakthrough in system structure from three-dimensional to two-dimensional, greatly reducing the size and weight of the aerial imaging system, and making it easier to place in various locations.

[0033] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This application provides a schematic diagram of the structural framework of an aerial imaging device in certain embodiments;

[0036] Figure 2 This application provides a schematic diagram of the structural framework of an aerial imaging system in certain embodiments;

[0037] Figure 3 This application provides a schematic diagram of a curved optical waveguide substrate transmission diffraction optical waveguide structure and the principle of realizing aerial imaging in certain embodiments;

[0038] Figure 4 This application provides a schematic diagram of a curved optical waveguide substrate reflective diffractive optical waveguide structure and the principle of realizing aerial imaging in certain embodiments;

[0039] Figure 5 This application provides a schematic diagram of a curved lens reflective diffractive waveguide structure and its principle for achieving aerial imaging, based on certain embodiments.

[0040] Figure 6 This application provides a schematic diagram of a curved lens transmission diffraction waveguide structure and its principle for achieving aerial imaging, based on certain embodiments.

[0041] Figure 7 This application provides a schematic diagram of a convex lens structure in certain embodiments;

[0042] Figure 8 This application provides a schematic diagram of a curved optical waveguide substrate structure in certain embodiments;

[0043] Figure 9 This application provides a schematic diagram of another curved optical waveguide substrate structure in certain embodiments;

[0044] Figure 10This application provides a schematic diagram of a one-dimensional grating two-dimensional pupil expansion structure in certain embodiments;

[0045] Figure 11 This application provides a schematic diagram of a two-dimensional grating two-dimensional pupil expansion structure in certain embodiments.

[0046] Explanation of reference numerals in the attached figures:

[0047] 1. Optical waveguide unit; 11. Coupler element; 12. Waveguide substrate; 121. First surface of waveguide substrate facing the real image; 122. Second surface of waveguide substrate facing away from the real image; 13. Coupler element; 14. Convex lens; 141. Third surface of convex lens facing the real image; 15. Deflection element; 2. Real image; 3. Micro-projection optical engine; 31. Microdisplay; 32. Collimator; 4. Human eye; 5X, rays from the leftmost edge view; 6X, rays from the center view; 7X, rays from the rightmost edge view. Detailed Implementation

[0048] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. Furthermore, it should be understood that the specific embodiments described herein are only for illustration and explanation of this application and are not intended to limit this application.

[0049] With the increasing number of cars on the road, the in-cabin experience, as a third space besides living and working, is becoming increasingly important. In the smart cockpit of a car, aerial imaging technology can replace the traditional center console display, projecting navigation information, entertainment content, and more directly in front of the driver. Aerial imaging expands the visual space within the cockpit, making information display more intuitive, immersive, and 3D images more vivid, greatly enhancing the viewing experience. However, related technologies for aerial imaging display solutions suffer from problems such as large system size and weight. For example, some aerial imaging solutions use an "equivalent negative refractive index plate" scheme, which can achieve aerial imaging effects, but the overall "three-dimensional" volume of the imaging system is large. The display module needs to be at a certain angle and distance from the imaging component, i.e., the equivalent negative refractive index plate, which severely restricts its placement and causes interference with multiple components inside the vehicle, such as air conditioning pipes and vents, requiring cutting or adjustments to avoid interference, which is very inconvenient. Some aerial imaging solutions use "multi-freeform surface" internal projection large field of view HUD (Head-Up Display) to achieve aerial imaging, but the system is relatively complex and the three-dimensional structure occupies a lot of space, making it very inconvenient to arrange inside the vehicle.

[0050] To address the aforementioned problems, this application provides an aerial imaging device, combined with... Figure 1-10 As shown, it includes:

[0051] Optical waveguide unit 1 has a curved surface structure. The optical waveguide unit 1 is used to converge image light rays in the air through the curved surface structure to form a real image 2.

[0052] In this context, the optical waveguide unit can be understood to include, but is not limited to, units used for efficient transmission, guidance, modulation, and expansion of optical signals, ensuring that light rays are transmitted from the image source (micro-projection optical engine) to the aerial target display area along a specific path to form a floating real image; the curved structure can include, but is not limited to, specific curved shape designs (such as spherical, aspherical, parabolic, ellipsoidal, or other optical curved surfaces), and the curved structure can be the surface of the waveguide substrate, a curved lens (such as a convex lens), etc.; the real image can include, but is not limited to, a visible image formed by the actual convergence of light rays at a certain point in the air, which can be observed without wearing glasses.

[0053] Specifically, the image light received by the optical waveguide unit 1 may include, but is not limited to, image light generated by the light source (such as an optomechanical system) of the aerial imaging device itself, or image light sent from other external devices or light sources. These image lights are collimated and modulated before entering the optical waveguide unit 1. The optical waveguide unit 1 uses a curved surface structure to control the propagation path of the light, ultimately converging it at a specific location in the air to form a real image 2. This image then continues to propagate to the human eye. After receiving the light from each field of view, the human eye intuitively traces the light back to the real image 2 based on everyday experience, thus observing the aerial image. Compared to related technologies, aerial imaging display solutions suffer from larger system size and heavier weight. Optical waveguide technology also has significant advantages in thickness and weight compared to solid LCD screens, achieving full-color effects with a single panel thickness of less than 2mm. With the addition of a freeform surface, the thickness can be controlled to within 10mm. This application adopts a diffractive waveguide aerial imaging scheme. By introducing a curved structure into the waveguide unit 1, the propagation path of light is adjusted, and the image light rays are converged in the air to form a real image. This achieves a breakthrough in system structure from three-dimensional to two-dimensional, greatly reducing the volume and weight of the aerial imaging system, and making it easier to place in various positions such as on a vehicle.

[0054] In some implementations, combined Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, the curved structure is disposed on the side of the optical waveguide unit 1 facing the real image 2.

[0055] Specifically, the optical waveguide unit 1 uses a curved structure to converge image light rays in the air to form a real image 2. The curved structure is located on the side of the optical waveguide unit 1 facing the real image 2, which can significantly improve the imaging performance and optical efficiency of the system. At the same time, it can reduce the use of additional optical components (such as lenses and prisms) and simplify the system structure.

[0056] In some implementations, combined Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, the curvature of the surface structure is inversely correlated with the size of the real image 2.

[0057] Specifically, the greater the curvature of the curved surface structure, the smaller the size of the real image 2, meaning a smaller image magnification. By employing a diffractive waveguide aerial imaging scheme and adjusting the curvature of the curved surface structure, the image achieves 1:N magnification, resulting in a larger field of view and viewing range, a larger image size, and a better user experience.

[0058] In some implementations, combined Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, the curvature of the surface structure is inversely correlated with the distance between the real image 2 and the optical waveguide unit 1.

[0059] Specifically, the greater the curvature of the curved surface structure, the closer the distance between the real image 2 and the optical waveguide unit 1, meaning the closer the focal point of the image rays. Employing a diffractive waveguide aerial imaging scheme, the aerial imaging position can be adjusted by changing the curvature of the curved surface structure, adapting to more scenarios. Especially in complex and crowded scenarios inside vehicles, the curvature can be adjusted according to different installation positions, thereby adjusting the aerial imaging position. This allows for the formation of a real image 2 at a suitable position close to the passenger, facilitating interaction and significantly improving the user experience.

[0060] In some implementations, combined Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, the curved surface structure includes concave and / or convex surfaces.

[0061] In some implementations, combined Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, the optical waveguide unit 1 includes a coupling element 11, a waveguide substrate 12, and a coupling element 13.

[0062] Coupler element 11 is used to couple image light rays into waveguide substrate 12;

[0063] Waveguide substrate 12 is used to transmit image light;

[0064] The coupling element 13 is used to couple out image light rays.

[0065] In this context, the coupling element can be understood as, but is not limited to, a diffraction structure located on the surface of the waveguide substrate. Its function is to couple the image light received by the aerial imaging device into the waveguide substrate, allowing it to be transmitted within the waveguide substrate via total internal reflection. The coupling element can be a surface relief grating, a volume holographic grating, or may include, but is not limited to, tilted sides, reflective elements, refractive prisms, photonic crystals, etc. The waveguide substrate can be, but is not limited to, made of a high refractive index material (such as glass or polymer) and have a curved surface structure. Its function is to guide the light to be transmitted internally via total internal reflection. The coupling element can be, but is not limited to, a diffraction structure located on the surface of the waveguide substrate, such as a surface relief grating or a volume holographic grating. Its function is to couple the total internally reflected light from the waveguide substrate out of the waveguide substrate, forming visible multi-field-of-view rays.

[0066] Specifically, the image light received by the aerial imaging device is coupled into the waveguide substrate 12 through the coupling element 11. Then, the image light is transmitted through a distance of total internal reflection in the waveguide substrate 12 and reaches the coupling element 13, and is coupled out of the waveguide substrate 12 through the coupling element 13.

[0067] In some implementations, combined Figure 3 , Figure 4 , Figure 8 and Figure 9 As shown, the waveguide substrate 12 is used to transmit and modulate image light, and the first surface 121 of the waveguide substrate 12 facing the real image 2 is concave.

[0068] The coupling element 13 is used to couple out image rays and converge them in the air to form a real image 2.

[0069] This can be understood as the first surface 121 of the waveguide substrate 12 facing the real image 2 being concave, which may include, but is not limited to, modulating the light rays at each field of view to change the light propagation path. For example, the waveguide substrate may have some or all of its surface facing the real image 2 being concave, and the surface of the waveguide substrate facing away from the real image 2 may be a planar structure, a curved structure, etc.

[0070] Specifically, the image light received by the aerial imaging device is coupled into the waveguide substrate 12 through the coupling element 11. The image light then travels a distance within the waveguide substrate 12 via total internal reflection before reaching the coupling element 13. Since the first surface 121 of the waveguide substrate 12 facing the real image 2 is concave, it can modulate the light rays at each field of view to change the light propagation path, causing the light rays from each field of view to converge at a certain position in the air after being coupled out by the coupling element 13, forming the real image 2. This aerial imaging scheme using diffractive waveguides, by designing a curved structure on the bottom of the waveguide substrate 22, adjusts the light propagation path and converges the image light rays in the air to form a real image. This achieves a breakthrough in system structure from three-dimensional to two-dimensional, significantly reducing the size and weight of the aerial imaging system. Simultaneously, the aerial imaging scheme replaces the traditional solid screen, resulting in better 3D display effects. Furthermore, since the touch interaction position is in the air, there is no cross-contamination, and the screen will not be damaged by scratches, oil stains, or other contamination. The single-sided curved design of the waveguide substrate 12 reduces processing difficulty and cost.

[0071] In some implementations, combined Figure 3 , Figure 4 and Figure 8 As shown, the second surface 122 of the waveguide substrate 12 facing away from the real image 2 is a convex surface, and the concave and convex surfaces have the same curvature.

[0072] Specifically, the waveguide substrate 12 features a symmetrical curved surface structure. The first surface 121 facing the real image 2 is concave, and the second surface 122 facing away from the real image 2 is convex. The curvatures of the first and second surfaces are identical, meaning the concave and convex surfaces have the same curvature. This double-curved surface balances the light distribution within the waveguide, improving the uniformity and brightness of the emitted light. It supports multi-level optical path adjustments, enabling more complex optical functions. Furthermore, it allows image light rays to be effectively converged during propagation, forming a high-brightness floating real image.

[0073] In one specific embodiment, the waveguide substrate 12 is a curved structure. The curved waveguide substrate 12 can be freely bent by the optical waveguide itself, as described by the XY polynomial. The radius of curvature gradually changes in the horizontal direction (matching the horizontal rotation range of the human eye), while the curvature in the vertical direction is fixed (reducing processing complexity). This allows for precise modulation of the light rays from each field of view of the image source, so that the light rays from each exit pupil are first focused and then diverged, thus achieving a real image in the air.

[0074] In some implementations, combined Figure 5 , Figure 6 and Figure 7 As shown, the optical waveguide unit 1 also includes a convex lens 14.

[0075] The coupling element 13 is used to couple image light to the convex lens 14;

[0076] The convex lens 14 is used to converge the image light rays in the air to form a real image 2.

[0077] In this context, a convex lens can be understood to include, but is not limited to, lenses that refract light rays to converge diverging light rays to a specific position, thereby forming a real image in the air. A convex lens can be a single-sided convex lens (where only one side is convex) or a double-sided convex lens (where both sides are convex).

[0078] Specifically, the image light received by the aerial imaging device is coupled into the waveguide substrate 12 through the coupling element 11. The image light then undergoes total internal reflection over a distance within the waveguide substrate 12 before reaching the coupling element 13. The coupling element 13 then couples the image light out to the convex lens 14. After proper design, the convex lens 14 is positioned at the corresponding location in the coupling area of ​​the diffractive waveguide, modulating the light rays at each field of view. The convex lens 14 converges the image light in the air to form a real image 2. This aerial imaging scheme using diffractive waveguides, by introducing a convex lens into the waveguide unit and adjusting the light propagation path, converges the image light in the air to form a real image, achieving a breakthrough in system structure from three-dimensional to two-dimensional, significantly reducing the size and weight of the aerial imaging system. Furthermore, the aerial imaging scheme replaces the traditional physical screen, providing better 3D display effects. Since the touch interaction point is in the air, there is no risk of cross-contamination or damage to the screen such as scratches or oil stains.

[0079] In some implementations, combined Figure 5 , Figure 6 and Figure 7 As shown, the third surface 141 of the convex lens 14 on the side facing the real image 2 is convex.

[0080] Specifically, the third surface 141 of the convex lens 14 facing the real image 2 has a convex structure. The coupling element 13 couples the image light rays to the convex lens 14, and the third surface 141 of the convex lens 14 converges the image light rays in the air to form the real image 2. As a single optical element, the convex lens can replace complex lens groups or waveguide structures, reducing system complexity.

[0081] In one specific embodiment, the freeform surface of the convex lens 14, with its highly flexible surface design, can flexibly correct aberrations that are difficult to eliminate with traditional spherical / aspherical surfaces (such as asymmetric coma and field curvature in large fields of view), especially showing significant advantages in off-axis imaging and large field-of-view systems. The freeform surface of the convex lens 14 is used to focus multi-field parallel beams from waveguide coupling to form aerial imaging. The mathematical model of this freeform surface can use Zernike polynomials to correct spherical aberration and coma, and then superimpose higher-order terms to optimize field curvature. The freeform surface polynomial coefficients are gradually released from low to high order, such as first optimizing the 4th order term, and then adding the 6th and 8th orders, to avoid "overfitting" due to too many variables. A phased optimization strategy is adopted. First, global optimization is performed: using a genetic algorithm or simulated annealing algorithm, the optimal initial solution is searched in a large variable space (focusing on optimizing low-order aberrations). Then, local optimization is performed: switching to damped least squares (DLS) to finely adjust the higher-order terms of the freeform surface and minimize the aberration evaluation function (such as MTF weighted error and wavefront error sum of squares). Finally, aberration balancing is performed: when the image quality of the edge field of view is poor, a small amount of central field of view performance can be sacrificed (such as MTF decreasing from 0.7 to 0.65) in exchange for improving the edge field of view MTF (modulation transfer function) from 0.3 to 0.45, thus achieving full field-of-view equalization.

[0082] In some implementations, combined Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, the coupling element 11 and the coupling element 13 are surface relief gratings or volume holographic gratings. By using surface relief gratings or volume holographic gratings, high diffraction efficiency, large field of view, and high stability can be achieved.

[0083] Optionally, the coupling element 11 is a tilted side surface. The tilted side surface of the waveguide substrate 12 can be used as the functional surface of the optical coupling mechanism. The tilted side surface faces the projection light engine, so that the image light projected by the projection light engine is refracted at the tilted side surface to couple into the waveguide substrate. In order to reduce reflection loss, an anti-reflection film can also be provided on the tilted side surface.

[0084] Optionally, the coupling element 11 is a reflective element, which can be correspondingly disposed on the inclined side of the waveguide substrate 22. The first surface of the waveguide substrate 12 faces the projection light engine, so that the image light is reflected at the inclined side to couple into the waveguide substrate 12. The reflective element may include a reflective film or be composed of a prism coated with a reflective film.

[0085] Optionally, the coupling element 11 is a refractive prism with a coupling side and an inclined surface extending at an angle relative to the coupling side. The inclined surface of the refractive prism is attached to the second surface of the waveguide substrate, and the coupling side serves as the functional surface of the optical coupling mechanism, which can couple light into the waveguide substrate 12.

[0086] Optionally, the coupling element 11 is a photonic crystal. The optical signal transmission structure is precisely designed and controlled through micro-nano optics, and optical coupling is achieved by using spatial optical path coupling methods such as lens transformation.

[0087] In some implementations, combined Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, the coupling diffraction efficiency of the coupling element 13 gradually increases along the direction of image light transmission.

[0088] In this context, the coupling diffraction efficiency can be understood as, but is not limited to, the efficiency by which the coupling element couples light propagating within the waveguide substrate out of the waveguide substrate, i.e., the ratio of the power of the output light to the power of the input light.

[0089] Specifically, in one embodiment, taking a surface-embossed grating as an example, the diffraction efficiency of the coupling grating can be optimized to a target value using a global optimization algorithm such as particle swarm optimization combined with rigorous coupled-wave analysis. Optimizable parameters include the material of the waveguide substrate 12, the material of the coupling grating (coupled-in element 11 and coupled-out element 13), and the shape of the coupling grating, such as a rectangular grating, a blazed grating, a tilted grating, or a trapezoidal grating, to obtain the target diffraction efficiency. For example, after optimization, the coupled-out element 13 can achieve a diffraction efficiency of 5X at the exit point of each ray from the leftmost edge viewpoint that is less than that of 6X at the exit point of each ray from the center viewpoint, and a diffraction efficiency of 6X at the exit point of each ray from the center viewpoint that is less than that of 7X at the exit point of each ray from the rightmost edge viewpoint. The reflection efficiency gradually decreases along the transmission direction, while the diffraction coupling efficiency gradually increases, resulting in excellent uniformity of the light rays exiting the pupil.

[0090] In some implementations, combined Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 10 and Figure 11 As shown, the coupling element 13 is a one-dimensional grating or a two-dimensional grating.

[0091] In this context, it can be understood that a one-dimensional grating may include, but is not limited to, a grating with a periodic structure in only one direction (such as lateral or longitudinal periodic etching); a two-dimensional grating may include, but is not limited to, a grating with a periodic structure in both directions (such as lateral and longitudinal periodic etching).

[0092] Specifically, in some embodiments, the coupling element 13 can be as follows: Figure 10 The one-dimensional grating shown, or as Figure 11 The two-dimensional grating shown. In one specific embodiment, as... Figure 11 This demonstrates how a two-dimensional grating is used as the coupling element 13 in a diffractive waveguide to achieve a two-dimensional pupil expansion effect. The two-dimensional grating simultaneously functions as both a pupil expander and an exit pupil. Its unit structure micro-units can use cylinders, prismatic prisms, or other polygonal prisms, making the entire optical system more compact. Using two-dimensional pupil expansion technology can significantly reduce the size of micro-projection optical engines (such as those integrated into aerial imaging devices).

[0093] In some implementations, combined Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 10 As shown, the optical waveguide unit 1 also includes a transition element 15, and the coupling element 13 is a one-dimensional grating.

[0094] The turning element 15 is used to turn the image light transmitted from the waveguide substrate 12 into a different optical path and then transmit it to the coupling element 13, so as to achieve pupil expansion of the image light.

[0095] In this context, the transition element can be understood to include, but is not limited to, a periodic structure used to change the direction of light propagation within the waveguide, typically achieving pupil expansion and diffraction of the optical path through reflection and diffraction.

[0096] Specifically, the image light received by the aerial imaging device is coupled into the waveguide substrate 12 via the coupling element 11. Then, after a distance of total internal reflection within the waveguide substrate 12, the image light reaches the deflection element 15. The deflection element 15 continuously deflects the image light in multiple directions before transmitting it through the waveguide substrate 12 to the output element 13. The introduction of the deflection element 15 allows for a large FOV and large eyebox display even when the output element 13 is a one-dimensional grating, enhancing the immersive experience.

[0097] In some implementations, the transition element 15 may include, but is not limited to, a surface relief grating or a volume holographic grating.

[0098] In some implementations, combined Figure 3 and Figure 5 As shown, the coupling element and the coupling element are of the transmission type; or, combined with Figure 4 and Figure 6 As shown, the input and output elements are reflective.

[0099] This application provides an aerial imaging system, combined with... Figure 2-6 include:

[0100] Micro-projection optical engine 3, used to output image light; and

[0101] The aforementioned aerial imaging device is used to converge image rays in the air to form a real image 2.

[0102] In this context, the micro-projection optical engine can be understood to include, but is not limited to, the core of image generation, responsible for converting digital signals into high-resolution, high-brightness light signals and controlling the optical path.

[0103] Specifically, the micro-projection optical engine 3 generates image rays, which are then collimated and modulated before entering the optical waveguide unit 1. The optical waveguide unit 1 uses a curved structure to control the propagation path of the light rays, ultimately converging them at a specific location in the air to form a real image 2. This image then continues to propagate to the human eye. After receiving the light rays from each field of view, the human eye intuitively traces the rays back to the real image 2 based on everyday experience, thus observing the aerial image. Compared to related technologies, aerial imaging display schemes suffer from larger system size and heavier weight. Optical waveguide technology also offers significant advantages in thickness and weight compared to solid LCD screens, achieving full-color effects with a single panel thickness of less than 2mm, and even with a freeform surface, the thickness can be controlled to within 10mm. This application employs a diffractive optical waveguide aerial imaging scheme. By introducing a curved structure into the optical waveguide unit 1 of the aerial imaging device, the propagation path of the light is adjusted, converging the image rays in the air to form a real image. This achieves a breakthrough in system structure from three-dimensional to two-dimensional, significantly reducing the size and weight of the aerial imaging system, making it easier to deploy in various locations.

[0104] In some implementations, combined Figure 2-6 As shown, the micro-projection optical engine 3 includes a microdisplay 31 and a collimator 32.

[0105] The microdisplay 31 is used to output image light;

[0106] Collimator 32 is used to convert image light into multi-field collimated parallel beams.

[0107] In this context, the microdisplay 31 can be understood to include, but is not limited to, Micro-LED (Micro Light Emitting Diode Display), LCD (Liquid Crystal Display), DLP (Digital Light Processor), LCOS (Liquid Crystal on Silicon), etc.; the collimator 32 can include, but is not limited to, conventional lens groups, Fresnel lenses, superlenses, metasurfaces, etc.

[0108] Specifically, the microdisplay 31 is responsible for converting the digital signal into high-resolution, high-brightness first image light and emitting it to the collimator 32. The collimator 32 then converts the image light into a multi-field collimated parallel beam, reducing the divergence angle of the light to facilitate coupling into the optical waveguide unit 1.

[0109] This application provides a vehicle that includes the aerial imaging system described above.

[0110] The aerial imaging system and vehicle based on diffractive waveguides are the preferred embodiments of this application. The aerial imaging display system can be arranged in different locations inside the vehicle according to different needs and application scenarios, such as the IP center console, in front of the passenger seat, the sunroof, the sun visor, and the headrests of the front seats. These different application scenarios will not be described separately to avoid unnecessary repetition.

[0111] In this specification, the terms "specifically," "optionally," "furthermore," "particularly," "conceptually," "even further," etc., refer to specific features, structures, materials, or characteristics described in connection with embodiments or examples that are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0112] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing a particular logical function or process, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the function involved, as should be understood by those skilled in the art to which embodiments of this application pertain.

[0113] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. An aerial imaging device, characterized in that, include: Optical waveguide unit (1), the optical waveguide unit (1) has a curved structure, the optical waveguide unit (1) is used to converge the received image light in the air through the curved structure to form a real image (2).

2. The apparatus according to claim 1, characterized in that, The curved structure is disposed on the side of the optical waveguide unit (1) facing the real image (2).

3. The apparatus according to claim 2, characterized in that, The curvature of the surface structure is inversely correlated with the size of the real image (2).

4. The apparatus according to claim 2 or 3, characterized in that, The curvature of the surface structure is inversely correlated with the distance between the real image (2) and the optical waveguide unit (1).

5. The apparatus according to any one of claims 1-4, characterized in that, The optical waveguide unit (1) includes a coupling element (11), a waveguide substrate (12), and a coupling element (13). The coupling element (11) is used to couple the image light into the waveguide substrate (12); The waveguide substrate (12) is used to transmit the image light; The coupling element (13) is used to couple out the image light.

6. The apparatus according to claim 5, characterized in that, The waveguide substrate (12) is used to transmit and modulate the image light, and the first surface (121) of the waveguide substrate (12) facing the real image (2) is concave. The coupling element (13) is used to couple the image light rays out and converge them in the air to form the real image (2).

7. The apparatus according to claim 6, characterized in that, The second surface (122) of the waveguide substrate (12) facing away from the real image (2) is a convex surface, and the concave surface and the convex surface have the same curvature.

8. The apparatus according to claim 5, characterized in that, The optical waveguide unit (1) also includes a convex lens (14). The coupling element (13) is used to couple the image light to the convex lens (14); The convex lens (14) is used to converge the image light rays in the air to form the real image (2).

9. The apparatus according to claim 8, characterized in that, The third surface (141) of the convex lens (14) on the side facing the real image (2) is convex.

10. The apparatus according to claim 5, characterized in that, The coupling element (11) and the coupling element (13) are surface relief gratings or volume holographic gratings.

11. The apparatus according to claim 5, characterized in that, The coupling diffraction efficiency of the coupling element (13) gradually increases along the direction of image light transmission.

12. The apparatus according to claim 5, characterized in that, The coupling element (13) is a one-dimensional grating or a two-dimensional grating.

13. The apparatus according to claim 12, characterized in that, The optical waveguide unit (1) further includes a transition element (15), and the coupling element (13) is a one-dimensional grating. The turning element (15) is used to turn the optical path of the image light transmitted from the waveguide substrate (12) and transmit it to the coupling element (13) to realize pupil expansion of the image light.

14. An aerial imaging system, characterized in that, include: Micro-projection optical engine (3), the micro-projection optical engine (3) is used to output image light; as well as The aerial imaging apparatus according to any one of claims 1-13, wherein the aerial imaging apparatus is used to converge the image light rays in the air to form a real image (2).

15. The system according to claim 14, characterized in that, The micro-projection optical engine (3) includes a microdisplay (31) and a collimator (32). The microdisplay (31) is used to output the image light; The collimator (32) is used to convert the image light into a multi-field collimated parallel beam.

16. A vehicle, characterized in that, The vehicle includes an aerial imaging device as claimed in any one of claims 1-13, or an aerial imaging system as claimed in claim 14 or 15.

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