Display device, display system, and vehicle

Abstract

The application discloses a display device, a display system and a vehicle. The display device comprises a planar member and a polarization volume holographic optical element, and the planar member is adapted to be arranged in a spaced manner with a light-transmitting display element. The polarization volume holographic optical element is arranged on a target surface of the planar member, and the polarization volume holographic optical element is adapted to diffract incident light to the light-transmitting display element, so that the light-transmitting display element reflects the light from the polarization volume holographic optical element to a preset area. In the display device, the display system and the vehicle, the polarization volume holographic optical element is arranged on the planar member instead of the light-transmitting display element with a certain curvature, so that the problem of wrinkles and deformation of the polarization volume holographic optical element of the intelligent cockpit can be prevented, and the final imaging effect is ensured, and the user experience is better.

Description

Technical Field

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

[0002] Head-up display (HUD) optical systems are now widely used in automotive displays. They present a virtual image in front of the viewer, allowing them to see the road ahead while simultaneously viewing the displayed scene. This effectively reduces the time and frequency drivers need to check the dashboard or GPS, improving driving safety. In related technologies, the liquid crystal holographic film of the display device is placed on light-transmitting display elements such as the windshield. However, because windshields and other light-transmitting display elements are free-form surfaces with curvature, the liquid crystal holographic film is prone to wrinkling and deformation when adhered to these elements. This causes changes in the local periodicity of the liquid crystal holographic film, affecting the imaging effect. Utility Model Content

[0003] This application provides a display device, a display system, and a vehicle to solve at least one of the aforementioned technical problems.

[0004] In a first aspect, this application provides a display device. The display device includes a planar component and a polarizing holographic optical element, the planar component being adapted to be disposed at a distance from a light-transmitting display element. The polarizing holographic optical element is disposed on a target surface of the planar component, and the polarizing holographic optical element is adapted to diffract incident light to the light-transmitting display element, so that the light-transmitting display element reflects the light from the polarizing holographic optical element to a predetermined area.

[0005] In some embodiments, the planar component includes a first target surface, and the polarizing holographic optical element includes a first polarizing holographic optical element disposed on the first target surface, the first polarizing holographic optical element being adapted to diffract incident light onto the light-transmitting display element.

[0006] In some embodiments, the planar component includes a plurality of different target surfaces, the polarizer holographic optical element includes a first polarizer holographic optical element disposed on one of the target surfaces, and the incident light is adapted to be diffracted by the first polarizer holographic optical element to the light-transmitting display element.

[0007] In some embodiments, the planar component includes multiple different target surfaces, the polarizer holographic optical element includes multiple polarizer holographic optical elements, the multiple polarizer holographic optical elements are respectively disposed on the multiple different target surfaces, and the incident light is adapted to be diffracted sequentially through the multiple polarizer holographic optical elements to the light-transmitting display element.

[0008] In some embodiments, where the planar component includes a plurality of different target surfaces, the plurality of different target surfaces may be constructed as a housing, at least one of the polarizer holographic optical elements is disposed on the inner surface of the housing, and the light-transmitting display element is adapted to be disposed on the outside of the housing.

[0009] In some embodiments, when the polarizer holographic optical element comprises a plurality of polarizer holographic optical elements, at least two of the plurality of polarizer holographic optical elements have opposite grating vectors.

[0010] In some embodiments, when there are multiple polarizer holographic optical elements, all of the multiple polarizer holographic optical elements are transmission-type elements.

[0011] In some embodiments, when the polarizer holographic optical element comprises multiple elements, all of the multiple polarizer holographic optical elements are reflective elements.

[0012] In some embodiments, when the polarizer holographic optical element comprises multiple elements, some of the multiple polarizer holographic optical elements are transmissive elements and others are reflective elements.

[0013] In some embodiments, when multiple polarizer holographic optical elements are included, the polarization selectivity of the multiple polarizer holographic optical elements is the same. All of the multiple polarizer holographic optical elements diffract right-handed circularly polarized light.

[0014] In some embodiments, when multiple polarizer holographic optical elements are included, the polarization selectivity of the multiple polarizer holographic optical elements is the same. All of the multiple polarizer holographic optical elements diffract left-handed circularly polarized light.

[0015] In some embodiments, the display device further includes a polarizing grating and a waveguide plate, the waveguide plate having an input end and an output end, the polarizing grating being disposed at the input end and adapted to couple light into the waveguide plate; the polarizing holographic optical element diffracts the light coupled out of the waveguide plate to the light-transmitting display element.

[0016] In some embodiments, the polarizer holographic optical element includes a transmissive element and at least one reflective element. The transmissive element is disposed at the coupling end of the waveguide plate and is adapted to transmit light coupled out of the waveguide plate to the reflective element. The reflective element is adapted to reflect light from the transmissive element to the light-transmitting display element.

[0017] In some embodiments, the polarizer holographic optical element includes at least two reflective elements, wherein the reflective element disposed at the coupling end of the waveguide plate is adapted to reflect the light coupled out of the waveguide plate to the remaining reflective elements, and the remaining reflective elements are adapted to reflect the light to the light-transmitting display element.

[0018] In some embodiments, the polarizer holographic optical element includes a first functional layer, a second functional layer, and a third functional layer, which are stacked sequentially. The second functional layer is a first chiral cholesteric liquid crystal material, and the first and third functional layers are second chiral cholesteric liquid crystals. The chirality of the first chiral cholesteric liquid crystal material and the second chiral cholesteric liquid crystal material is different.

[0019] In some embodiments, the polarizer holographic optical element includes a first functional layer, a second functional layer, and a third functional layer, which are stacked sequentially. The first functional layer is adapted to diffract a first color of light, the second functional layer is adapted to diffract a second color of light, and the third functional layer is adapted to diffract a third color of light.

[0020] In some embodiments, the polarizer holographic optical element further includes a substrate layer, and the first functional layer, the second functional layer and the third functional layer are sequentially stacked on the substrate layer.

[0021] In some implementations, the first functional layer, the second functional layer, and the third functional layer have the same thickness.

[0022] In some embodiments, the first and third colors of the incident light are circularly polarized light with the same chirality, the first and second colors of the incident light are circularly polarized light with cross-chirality, and the third and second colors of the incident light are circularly polarized light with cross-chirality.

[0023] Secondly, this application provides a display system, which includes a light-transmitting display element and the display device described in any of the above embodiments.

[0024] In some embodiments, at least a portion of the light-transmitting display element is a surface with a predetermined curvature.

[0025] In some embodiments, the display system further includes an image source spaced apart from the polarizer holographic optical element and used to emit the incident light toward the polarizer holographic optical element.

[0026] Thirdly, this application provides a vehicle that includes the display device described in any of the above embodiments; or, the vehicle includes the display system described in any of the above embodiments.

[0027] In some embodiments, the light-transmitting display element includes at least the windshield of the vehicle.

[0028] In the display device, display system, and vehicle of this application, a polarizing holographic optical element is disposed on the target surface of a planar component. The polarizing holographic optical element is adapted to diffract incident light onto a light-transmitting display element, so that the light-transmitting display element reflects the light from the polarizing holographic optical element to a preset area (eye box area). That is, the polarizing holographic optical element in this application is disposed on a planar component, rather than on a light-transmitting display element with a certain curvature. This can prevent problems such as wrinkles and deformation of the polarizing holographic optical element, thereby ensuring the final imaging effect and providing a better user experience.

[0029] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0030] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, wherein: Figure 1 This is a schematic diagram of the structure of a head-up display system according to some embodiments of this application; Figure 2 This is a schematic diagram of the structure of a head-up display system according to other embodiments of this application; Figure 3 This is a schematic diagram of the structure of a head-up display system according to some embodiments of this application; Figure 4 This is a schematic diagram of the structure of a head-up display system according to some other embodiments of this application; Figure 5 This is a schematic diagram of beam modulation of a liquid crystal holographic element according to some embodiments of this application; Figure 6 This is a schematic diagram showing the partial structure and polarization response of a liquid crystal holographic element according to some embodiments of this application; Figure 7 This is a schematic diagram of the structure of a liquid crystal holographic element according to some embodiments of this application; Figure 8This is an exposure schematic diagram of a liquid crystal holographic element according to some embodiments of this application; Figure 9 This is a structural schematic diagram of a vehicle according to some embodiments of this application; Figure 10 This is a structural schematic diagram of a vehicle according to other embodiments of this application.

[0031] Explanation of key component symbols: 1000 vehicles; 300 display system; 100 Display device; 200 Light-transmitting display element; 70 Image source; 10. Flat component; A. Preset area; 30 Polarizing holographic optical element, 31 First polarizing holographic optical element, 33 Second polarizing holographic optical element, 35 First functional layer, 37 Second functional layer, 39 Third functional layer; 34. Polarizing grating; 50 waveguide plate. Detailed Implementation

[0032] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0033] In the description of this application, it should be understood that the terms "center", "length", "upper", "lower", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0034] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0035] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0036] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0037] Head-up display (HUD) optical systems are now widely used in automotive displays. They present a virtual image in front of the viewer, allowing them to see the road ahead while simultaneously viewing the displayed scene. This effectively reduces the time and frequency drivers need to observe the dashboard or GPS, improving driving safety. In related technologies, the liquid crystal holographic film of the display device is applied to light-transmitting display elements such as windshields. Since windshields and other light-transmitting display elements are free-form surfaces with curvature, the liquid crystal holographic film is prone to wrinkling and deformation when adhered to these elements, causing changes in the local periodicity of the film and affecting the imaging effect. To solve the above problems, this application provides a display device 100 (… Figure 1 , Figure 2 , Figure 3 or Figure 4 As shown), display system 300 ( Figure 1 , Figure 2 , Figure 3 or Figure 4 (as shown) and 1000 vehicles ( Figure 9 or Figure 10 (As shown).

[0038] Please see Figure 9 and combined Figure 1 , Figure 2 , Figure 3 or Figure 4This application provides a vehicle 1000, which includes a display device 100. The vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle, or a range-extended electric vehicle, etc., and is not limited in this application.

[0039] Since the vehicle 1000 in this embodiment includes a display device 100, it is understood that the vehicle 1000 has at least the same beneficial effects as the display device 100. Therefore, for the beneficial effects of the vehicle 1000, please refer to the beneficial effects of the display device 100 described below.

[0040] Please see Figure 10 and combined Figure 1 , Figure 2 , Figure 3 or Figure 4 This application provides a vehicle 1000, which includes a display system 300. The vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle, or a range-extended electric vehicle, etc., and is not limited in this application.

[0041] Since the vehicle 1000 in this embodiment includes a display system 300, it is understood that the vehicle 1000 has at least the same beneficial effects as the display system 300. Therefore, for the beneficial effects of the vehicle 1000, please refer to the beneficial effects of the display system 300 described below.

[0042] Please see Figure 1 , Figure 2 , Figure 3 or Figure 4 This application provides a display system 300, which includes a display device 100.

[0043] It should be noted that, in some embodiments, the display system 300 may include, but is not limited to, a head-up display (HUD). A head-up display is an optoelectronic display device that can optically project information such as vehicle speed and navigation onto the driver's line of sight (usually located on the windshield) to form a virtual image superimposed on the external road environment.

[0044] Since the display system 300 in this embodiment includes the display device 100, it is understood that the display system 300 includes at least the same beneficial effects as the display device 100. Therefore, for the beneficial effects of the display system 300, please refer to the beneficial effects of the display device 100 described below.

[0045] In some embodiments, the display system 300 further includes a light-transmitting display element 200. The light-transmitting display element 200 is a transparent component used to transmit ambient light and carry displayed images, allowing users to observe the external real scene through the element while receiving optical image information from the display device 100 to achieve a virtual-real fusion display effect.

[0046] In some embodiments of this application, at least a portion of the light-transmitting display element 200 is a curved surface with a predetermined curvature. That is, at least a portion of the surface of the light-transmitting display element is not planar in space, but has a pre-designed curved shape. The predetermined curvature can be a spherical curvature with a single radius, or it can be an aspherical curvature (such as a parabola, ellipsoid, or freeform surface).

[0047] In some embodiments of this application, the light-transmitting display element 200 includes at least the windshield of the vehicle 1000. It should be noted that the light-transmitting display element 200 may also include side windows of the vehicle 1000, sunroof of the vehicle 1000, transparent lenses for AR glasses, and goggles for a helmet-mounted display, etc. For ease of understanding, the following embodiments will use the windshield of the vehicle 1000 as an example for explanation.

[0048] Please see Figure 1 , Figure 2 , Figure 3 or Figure 4 This application provides a display device 100. The display device 100 includes a planar component 10 and a polarizer holographic optical element 30. The planar component 10 is adapted to be spaced apart from a light-transmitting display element 200. The polarizer holographic optical element 30 is disposed on a target surface of the planar component 10. The polarizer holographic optical element 30 is adapted to diffract incident light to the light-transmitting display element 200, so that the light-transmitting display element 200 reflects the light from the polarizer holographic optical element 30 to a preset area A. It should be noted that the structure and characteristics of the display system 300 and display device 100 in this embodiment are basically the same as the combination and characteristics of the display system 300 and display device 100 of the display system 300 in the above embodiments. Therefore, the explanations and descriptions of the display system 300 and display device 100 in this embodiment are applicable to the display system 300 and display device 100 of the display system 300 in the above embodiments.

[0049] The display device 100 is a device used to present images, videos, or text information. It converts electrical signals into visual images through the coordinated operation of optical and electronic components. The display device 100 can be applied to augmented reality (AR) devices, head-up displays (HUDs), transparent displays, in-vehicle display systems 300, or head-mounted display devices.

[0050] The planar component 10 is a structure in the display device 100 used to carry or support optical elements (polarizer holographic optical element 30) and cooperate with the light-transmitting display element 200 to form an optical path. The target surface of the planar component 10 can be a plane. The planar component 10 may be provided with mounting and positioning structures (such as slots, threaded holes, or adhesive surfaces) for fixing the polarizer holographic optical element 30 or other optical components.

[0051] A polarization volume hologram (PVH) is a diffractive optical element based on a liquid crystal polymer material. Its internal structure features a periodically arranged liquid crystal molecule orientation, enabling selective modulation of the polarization state and phase of incident light, thereby achieving functions such as beam deflection, focusing, beam splitting, or imaging. The polarization volume hologram 30 is made of liquid crystal polymer material, and specific optical interference fringes are recorded within it using optical alignment techniques or holographic interference exposure processes. The polarization volume hologram 30 features high diffraction efficiency, a wide viewing angle, and polarization selectivity, making it suitable for optical waveguide coupling input or output in augmented reality display systems. In some embodiments of this application, the polarization volume hologram 30 may include, but is not limited to, freeform polarization volume holograms (F-PVH).

[0052] Please combine Figure 10 When the light-transmitting display element 200 is the windshield of the vehicle 1000, the display device 100 can cooperate with the light-transmitting display element 200 to project information such as vehicle speed and navigation into the driver's line of sight in an optical manner, so that the driver can obtain driving information while keeping his eyes on the road ahead, thereby reducing the time the driver's eyes are off the road and improving driving safety.

[0053] In some embodiments of this application, the preset region A can be an eyebox region, which is a spatial range in which the human eye can clearly observe a complete virtual image. It is usually defined as a three-dimensional region with a certain width, height, and depth. Within the eyebox region, the observer's eye can see a complete image without distortion or missing parts, regardless of its position. When the eye moves out of this region, the image will appear partially missing, blurred, or completely disappear.

[0054] It should be noted that the fabrication of the polarizer holographic optical element 30 is based on a spin-coating process, which cannot be performed directly on the windshield. Therefore, in general, a flexible substrate process is required to first fabricate the polarizer holographic optical element 30 on a plane and then transfer it to the windshield. However, since the windshield is not a plane but a free-form surface with curvature, i.e., the windshield is a complex surface with curvature in two directions, the polarizer holographic optical element 30 cannot be perfectly laid flat during transfer, which easily leads to deformation and other problems, resulting in changes in local periodicity and affecting the imaging effect.

[0055] In the display device 100 of this application embodiment, the polarizer holographic optical element 30 is disposed on the target surface of the planar member 10, rather than on the light-transmitting display element 200 with a certain curvature. This prevents the polarizer holographic optical element 30 from wrinkling or deforming, thereby ensuring the final imaging effect and providing a better user experience. Furthermore, the polarizer holographic optical element 30 is adapted to diffract incident light onto the light-transmitting display element 200 (windshield), so that the light-transmitting display element 200 reflects the light from the polarizer holographic optical element 30 to a preset area A (eye box area). This allows the driver to see the road conditions ahead while also seeing the scene on the display screen, effectively reducing the time and frequency of the driver's observation of the instrument panel or GPS, and improving driving safety.

[0056] Furthermore, in related technologies, incident light needs to be reflected by a mirror (such as a double freeform surface mirror) to the light-transmitting display element 200, and then reflected by the light-transmitting display element 200 to the preset area A. The mirror deflects the direction of the incident light based on geometric optics, and its light modulation capability depends on the device's shape. Therefore, the display device 100 using a double freeform surface mirror structure has limitations in terms of size optimization. In this application, a polarizing holographic optical element 30 is used to replace the mirror in the related technologies. The polarizing holographic optical element 30 diffracts the incident light onto the light-transmitting display element 200. Since the light can change its propagation direction more freely through diffraction, it helps to optimize the size of the display device 100, making it smaller and thus improving its applicability, for example, making it suitable for small vehicles.

[0057] Please see Figure 1 , Figure 2 , Figure 3 or Figure 4 and combined Figure 10 In some embodiments, the display system 300 further includes an image source 70, which is spaced apart from the polarizer holographic optical element 30 and is used to emit light toward the polarizer holographic optical element 30.

[0058] The image source 70 is a component capable of emitting light carrying image information. The image information includes dashboard information and navigation information; of course, it can also include other driving information, which is not limited in this application. Therefore, the driver can see both dashboard and navigation information while clearly seeing the road conditions ahead, which can significantly improve the vehicle's speed (1000 km / h). Figure 9 or Figure 10 (As shown) Driving safety. It should be noted that in some embodiments, the image source 70 can be a non-laser image source (e.g., TFT-LCD, DLP projection, LCOS, etc.) or a laser image source (e.g., LBS, laser DLP, laser LCoS, etc.). Non-laser image sources have a wider spectral bandwidth, while laser image sources have a narrower spectral bandwidth, which can be approximated as a single wavelength.

[0059] Please see Figure 4 In some embodiments of this application, the planar component 10 includes a first target surface, and the polarizer holographic optical element 30 includes a first polarizer holographic optical element 31. The first polarizer holographic optical element 31 is disposed on the first target surface and is adapted to diffract incident light onto the light-transmitting display element 200.

[0060] The first target surface can be a plane. The first polarizer holographic optical element 31 can be a polarizer holographic optical element 30 with a non-periodic or non-uniform grating structure recorded in a liquid crystal material using optical alignment technology. That is, the first polarizer holographic optical element 31 can be a free-form polarization volume hologram (F-PVH). It should be noted that in this embodiment, the image source 70 can be a laser image source. In this case, the display device 100 does not need to use two polarizer holographic optical elements 30 to compensate for single-channel chromatic aberration.

[0061] Please see Figure 4 In some embodiments of this application, the planar component 10 includes a plurality of different target surfaces, and the polarizer holographic optical element 30 includes a first polarizer holographic optical element 31, which is disposed on one of the target surfaces. The incident light is adapted to be diffracted by the first polarizer holographic optical element 31 to the light-transmitting display element 200.

[0062] The first polarizer holographic optical element 31 can be a polarizer holographic optical element 30 with a non-periodic or non-uniform grating structure recorded in a liquid crystal material using optical alignment technology. That is, the first polarizer holographic optical element 31 can be a free-form polarization volume hologram (F-PVH). It should be noted that in this embodiment, the image source 70 can be a laser image source; in this case, the display device 100 does not need to use two polarizer holographic optical elements 30 to compensate for single-channel chromatic aberration.

[0063] Please see Figure 1 , Figure 2 or Figure 3 In some embodiments of this application, the planar component 10 includes a plurality of different target surfaces, and the polarizer holographic optical element 30 includes a plurality of polarizer holographic optical elements 30 respectively disposed on a plurality of different target surfaces. The incident light is adapted to be diffracted by the plurality of polarizer holographic optical elements 30 in sequence to the light-transmitting display element 200.

[0064] Specifically, in some embodiments, the polarizer holographic optical element 30 includes multiple polarizer holographic optical elements 30, which may include a first polarizer holographic optical element 31 and a second polarizer holographic optical element 33. The first polarizer holographic optical element 31 is adapted to diffract incident light to the second polarizer holographic optical element, and the second polarizer holographic optical element is adapted to diffract light from the first polarizer holographic optical element to the light-transmitting display element 200.

[0065] Both the first polarizer holographic optical element 31 and the second polarizer holographic optical element 33 can be polarizer holographic optical elements 30 that are recorded in liquid crystal materials using optical alignment techniques and have a non-periodic or non-uniform grating structure. That is, both the first polarizer holographic optical element 31 and the second polarizer holographic optical element 33 can be free-form polarization volume holograms (F-PVH). The structure and characteristics of the first polarizer holographic optical element 31 and the second polarizer holographic optical element 33 can be the same or different. For example, both the first polarizer holographic optical element 31 and the second polarizer holographic optical element 33 can be reflective elements; or, for another example, one of the first polarizer holographic optical element 31 and the second polarizer holographic optical element 33 can be a reflective element, while the other is a transmissive element.

[0066] It should be noted that the polarizing holographic optical element 30 modulates the incident light based on diffraction, and its diffraction angle can be calculated using the K vector: , ; Among them, K ix / K iy K is the component of the incident light wave vector in the x / y directions. dx / K dy Λx / Λy is the component of the diffracted light wave vector in the x / y direction, where Λx / Λy is the local grating period at any position of the polarizer holographic optical element 30. The magnitude of the wave vector is inversely proportional to the wavelength, therefore the diffracted light directions are not the same for different wavelengths, which is diffraction chromatic aberration. When there is only one polarizer holographic optical element 30, diffraction chromatic aberration cannot be avoided, and the aberration correction of one polarizer holographic optical element 30 can only be applied to one wavelength. Other wavelengths are prone to problems such as imaging position shift, blurring, and color fringing. Therefore, the display device 100 with only one polarizer holographic optical element 30 cannot achieve good imaging of the image source 70 with a certain spectral width.

[0067] In some embodiments of this application, the incident light is adapted to be diffracted sequentially through multiple polarizer holographic optical elements 30 to the light-transmitting display element 200. Each of the multiple polarizer holographic optical elements 30 has a certain optical power and simultaneously corrects aberrations generated by the light-transmitting display element 200. Furthermore, the optical path is folded among the multiple polarizer holographic optical elements 30, which improves space utilization, thereby reducing the size of the display device 100; it also allows the diffraction chromatic aberrations of the multiple polarizer holographic optical elements 30 to compensate for each other, thereby improving the imaging effect when using a non-laser image source 70.

[0068] For example, the light emitted from the image source 70 can be first diffracted by the first polarizer holographic optical element 31, then by the second polarizer holographic optical element 33, and finally reflected by the light-transmitting display element 200 onto the preset area A. Both the first polarizer holographic optical element 31 and the second polarizer holographic optical element 33 have a certain optical power and simultaneously correct the aberrations generated by the light-transmitting display element 200. Furthermore, the light path is folded between the first polarizer holographic optical element 31 and the second polarizer holographic optical element 33. This improves space utilization, thereby reducing the size of the display device 100; it also allows the diffraction chromatic aberrations of the first polarizer holographic optical element 31 and the second polarizer holographic optical element 33 to compensate for each other, thereby improving the imaging effect when using a non-laser image source 70.

[0069] In some embodiments, when the planar component 10 includes multiple different target surfaces, these multiple target surfaces can be constructed as a housing, with at least one polarizer holographic optical element 30 disposed on the inner surface of the housing, and the light-transmitting display element 200 adapted to be disposed on the outside of the housing. That is, the planar component 10 is a three-dimensional structure composed of multiple surfaces, which together constitute a housing, so that the planar component 10 can both serve a loading function, such as loading the polarizer holographic optical element 30, and a protective function, such as preventing dust and other impurities from contacting the polarizer holographic optical element 30 and affecting the imaging quality.

[0070] In addition, at least one polarizer holographic optical element 30 is disposed on the inner surface of the housing. Thus, the housing can encapsulate the polarizer holographic optical element 30 disposed on the inner surface of the housing, thereby helping to reduce interference from external stray light on the performance of the polarizer holographic optical element 30 and improving the contrast and clarity of the displayed image. It should be noted that, in some embodiments, the housing may be installed in a location such as behind the instrument panel or inside the dashboard space below the windshield of the vehicle 1000.

[0071] In some embodiments, when multiple polarizer holographic optical elements 30 are included, at least two of the multiple polarizer holographic optical elements 30 have opposite grating vectors. In this way, the multiple polarizer holographic optical elements 30 can achieve mutual compensation of diffraction chromatic aberration, effectively improving image quality. For example, the multiple polarizer holographic optical elements 30 include a first polarizer holographic optical element 31 and a second polarizer holographic optical element 33, and the grating vectors of the first polarizer holographic optical element 31 and the second polarizer holographic optical element 33 are opposite. For example, the grating vector of the first polarizer holographic optical element 31 is K1, and the grating vector of the second polarizer holographic optical element 33 is K2, where K2 = K1 (i.e., the two are equal in size and opposite in direction), at this time, the diffraction angle dispersion generated by the first polarizing holographic optical element 31 is canceled by the second polarizing holographic optical element 33.

[0072] In some embodiments of this application, when multiple polarizer holographic optical elements 30 are included, all of the multiple polarizer holographic optical elements 30 are transmissive elements. In other embodiments of this application, when multiple polarizer holographic optical elements 30 are included, all of the multiple polarizer holographic optical elements 30 are reflective elements. In still other embodiments of this application, when multiple polarizer holographic optical elements 30 are included, some of the multiple polarizer holographic optical elements 30 are transmissive elements, and others are reflective elements.

[0073] Among them, a transmission-type element refers to a polarizing holographic optical element in which incident light enters from one side of the element, is modulated by the internal diffraction structure, and then exits from the other side of the element. That is, a transmission-type polarizing holographic optical element performs transmission diffraction on the incident light, and the outgoing light and the incident light are located on opposite sides of the element.

[0074] A reflective element is a polarizing holographic optical element in which incident light enters from one side of the element, is modulated by the internal diffraction structure, and is reflected out from the same side of the element. In other words, a reflective polarizing holographic optical element performs reflective diffraction on the incident light, and the outgoing light is located on the same side of the element as the incident light.

[0075] Specifically, in the above embodiments, the plurality of polarizer holographic optical elements 30 can be transmissive elements and / or reflective elements, which allows the display device 100 to be flexibly designed according to factors such as spatial layout, light source position, observer's viewing angle and system cost, thus helping to improve the applicability of the display device 100. For example, in situations where space is relatively compact, reflective polarizer holographic optical elements can be used to fold the optical path and reduce the size.

[0076] Please see Figure 1 , Figure 2 , Figure 3 or Figure 4 and combined Figure 5 In some embodiments, when multiple polarizer holographic optical elements 30 are included, the multiple polarizer holographic optical elements 30 have the same polarization selectivity. All multiple polarizer holographic optical elements 30 diffract right-handed circularly polarized light; or, all multiple polarizer holographic optical elements 30 diffract left-handed circularly polarized light.

[0077] Specifically, in some embodiments, the polarizer holographic optical element 30 can be fabricated using cholesteric liquid crystal combined with optical alignment technology. Thus, the polarizer holographic optical element 30 exhibits polarization selectivity. For example, a polarizer holographic optical element 30 composed of a left-handed chiral cholesteric liquid crystal will only diffract left-handed circularly polarized light (LCP light), while right-handed circularly polarized light (RCP light) will pass directly through the polarizer holographic optical element 30. As another example, please refer to... Figure 5 The polarizer holographic optical element 30, which is composed of right-handed chiral cholesteric liquid crystal, only diffracts right-handed circularly polarized light (RCP light), while left-handed circularly polarized light (LCP light) passes directly through the polarizer holographic optical element 30.

[0078] Please combine Figure 6 , Figure 6 This describes the local structure and polarization response of a polarizer holographic optical element 30 according to some embodiments of this application. The local structure can be considered as a PVG with a specific period, wherein the liquid crystal pointing vector ( Figure 6 The black stripe structure in the image forms a two-dimensional periodic distribution under the action of the light alignment layer, thus constituting the grating plane. By designing the size and direction of the local period, the polarizer holographic optical element 30 can possess a complex phase profile, allowing for on-demand control of the diffracted light direction, thereby improving aberration correction capability. Furthermore, compared to traditional holographic optical elements (HOEs) based on materials such as silver halide and photopolymers, the polarizer holographic optical element 30 has a higher refractive index, thus maintaining high efficiency over a wider range of incident angles. Moreover, the efficiency of the polarizer holographic optical element 30 is determined by the pitch of the liquid crystal material and the thickness of the liquid crystal layer during fabrication; for example, the efficiency of the polarizer holographic optical element 30 is directly proportional to the thickness of the liquid crystal layer, and efficiency control is decoupled from the exposure process. Thus, aberration correction and efficiency control of the polarizer holographic optical element 30 can be achieved by optimizing the phase profile of the element and the liquid crystal parameters, respectively.

[0079] Please see Figure 2 or Figure 3 In some embodiments, when multiple polarizer holographic optical elements 30 are included, each polarizer holographic optical element 30 includes a polarizer grating 34, a transmissive element, and at least one reflective element. The display device 100 further includes a polarizer grating 34 and a waveguide plate 50, the waveguide plate 50 having an input end and an output end. The polarizer grating 34 is disposed at the input end and is adapted to couple light into the waveguide plate 50. The polarizer holographic optical elements 30 diffract the light coupled out of the waveguide plate 50 to the transmissive display element 200.

[0080] Among them, the polarization volume grating 34 (PVG) is a volume holographic grating prepared by optical alignment technology using liquid crystal material. It has a periodic refractive index modulation structure inside, and its diffraction efficiency strongly depends on the polarization state of the incident light. It usually diffracts only one type of circularly polarized light while transmitting circularly polarized light with the opposite rotation direction.

[0081] A waveguide 50 is a transparent, plate-shaped optical element used to guide light waves through total internal reflection, typically made of glass or a high-refractive-index polymer material. The waveguide 50 includes an input end for coupling light into the waveguide 50 and an output end for coupling light out of the waveguide 50.

[0082] Specifically, in the above embodiment, the polarizer grating 34 acts as an input coupler to couple the light emitted from the image source 70 into the waveguide plate 50. After propagating through the waveguide plate 50 via total internal reflection, the light is diffracted onto the windshield by the polarizer holographic optical element and finally reflected by the windshield to the preset area A. Since the waveguide plate 50 has an exit pupil expansion function, the image source 70 can be designed to be smaller in size when forming the same size eye box area, thereby further reducing the size of the display system 300.

[0083] Please combine Figure 2 In some embodiments, the polarizer holographic optical element 30 includes a transmissive element and at least one reflective element. The transmissive element is disposed at the coupling end of the waveguide plate 50 and is adapted to transmit light coupled out of the waveguide plate 50 to the reflective element. The reflective element is adapted to reflect light from the transmissive element to the light-transmitting display element 200.

[0084] Specifically, in the above embodiment, the plurality of polarizer holographic optical elements 30 includes two polarizer holographic optical elements 30, namely a first polarizer holographic optical element 31 and a second polarizer holographic optical element 33. The first polarizer holographic optical element 31 is a transmissive element, and the second polarizer holographic optical element 33 is a reflective element. The polarizer grating 34 acts as an ingress coupler to couple the light emitted from the image source 70 into the waveguide plate 50. After propagating through the waveguide plate 50 by total internal reflection, the light is coupled out by the first polarizer holographic optical element 31 to the second polarizer holographic optical element 33, then diffracted by the second polarizer holographic optical element 33 onto the windshield, and finally reflected by the windshield to the preset area A. Since the waveguide plate 50 has an exit pupil expansion function, the volume of the image source 70 can be designed to be smaller when forming the same size eye box area, thereby further reducing the volume of the display device 100.

[0085] Furthermore, the structure and characteristics of the first polarizer holographic optical element 31 and the second polarizer holographic optical element 33 in this embodiment are basically the same as those in the above embodiments, and will not be repeated here. Therefore, the first polarizer holographic optical element 31 and the second polarizer holographic optical element 33 in this embodiment also simultaneously possess optical power and aberration correction capabilities, and can perform diffraction chromatic aberration compensation optimization.

[0086] Please combine Figure 3In other embodiments, the polarizer holographic optical element 30 includes at least two reflective elements. The reflective element disposed at the coupling end is adapted to reflect the light coupled out of the waveguide plate 50 to the other reflective elements, and the other reflective elements are adapted to reflect the light to the light-transmitting display element 200.

[0087] It should be noted that the structure and characteristics of the polarizer grating 34 and waveguide plate 50 in this embodiment are basically the same as those in the above embodiments, and will not be described in detail here.

[0088] Specifically, in the above embodiment, the plurality of polarizer holographic optical elements 30 includes two polarizer holographic optical elements 30, which are a first polarizer holographic optical element 31 and a second polarizer holographic optical element 33, respectively. Both the first polarizer holographic optical element 31 and the second polarizer holographic optical element 33 are reflective elements. Light in the waveguide plate 50 can pass through the first polarizer holographic optical element 31 and be diffracted by it to the second polarizer holographic optical element 33.

[0089] Please see Figure 1 , Figure 2 , Figure 3 or Figure 4 and combined Figure 7 In some embodiments, the polarizer holographic optical element 30 includes a first functional layer 35, a second functional layer 37, and a third functional layer 39, which are stacked sequentially.

[0090] In some embodiments, the first functional layer 35 is adapted to diffract the first color red light, the second functional layer 37 is adapted to diffract the second color green light, and the third functional layer 39 is adapted to diffract the third color blue light.

[0091] Specifically, it should be noted that due to the limited wavelength response bandwidth of the polarizer holographic optical element 30, a single polarizer holographic optical element 30 cannot simultaneously exhibit high diffraction efficiency for multiple colors of light, thus preventing full-color display. However, the polarizer holographic optical element 30 in this application includes a first functional layer 35, a second functional layer 37, and a third functional layer 39. The first functional layer 35, the second functional layer 37, and the third functional layer 39 are designed for the three color channels respectively; that is, the first functional layer 35 diffracts only the first color light, the second functional layer 37 diffracts only the second color light, and the third functional layer 39 diffracts only the third color light. This increases the wavelength response bandwidth of the polarizer holographic optical element 30, contributing to the realization of full-color display.

[0092] In some embodiments, the first color light can be red light, the second color light can be green light, and the third color light can be blue light. That is, the first functional layer 35 is suitable for diffracting red light, the second functional layer 37 is suitable for diffracting green light, and the third functional layer 39 is suitable for diffracting blue light. Therefore, when the polarizer holographic optical element 30 includes the first functional layer 35, the second functional layer 37, and the third functional layer 39, and the first functional layer 35, the second functional layer 37, and the third functional layer 39 are designed for the R, G, and B color channels respectively, the wavelength response bandwidth of the polarizer holographic optical element 30 can be effectively increased. This eliminates the defect that the single polarizer holographic optical element 30 cannot simultaneously exhibit high diffraction efficiency for the R, G, and B color lights due to the limited wavelength response bandwidth of the polarizer holographic optical element 30, thereby helping to achieve full-color display.

[0093] In some embodiments, the second functional layer 37 is a first chiral cholesteric liquid crystal material, and the first functional layer 35 and the third functional layer 39 are second chiral cholesteric liquid crystal materials, wherein the chirality of the first chiral cholesteric liquid crystal material and the second chiral cholesteric liquid crystal material is different.

[0094] For example, such as Figure 7 As shown, the first cholesteric liquid crystal is a left-handed chiral cholesteric liquid crystal (L-CLC), and the second cholesteric liquid crystal can be a right-handed chiral cholesteric liquid crystal (R-CLC). Thus, by performing the aforementioned polarization design on the first functional layer 35, the second functional layer 37, and the third functional layer 39, green light will only diffract on the second functional layer 37. Since the wavelengths of blue and red light are significantly different, red light will only diffract on the first functional layer 35, and blue light will only diffract on the third functional layer 39. This ensures that the R, G, and B colors do not crosstalk between functional layers during diffraction, thereby guaranteeing the full-color display clarity of the display system 300.

[0095] In some embodiments, the first and third colors in the incident light are circularly polarized with the same chirality, the first and second colors in the incident light are circularly polarized with orthogonal chirality, and the third and second colors in the incident light are circularly polarized with orthogonal chirality. That is, the first and third colors in the incident light emitted by the image source 70 or other light-emitting structure are circularly polarized with the same chirality, the first and second colors in the incident light are circularly polarized with orthogonal chirality, and the third and second colors in the incident light are circularly polarized with orthogonal chirality. Thus, combined with the polarization design of the first functional layer 35, the second functional layer 37, and the third functional layer 39 in the above embodiments, it can be ensured that the three colors of light do not interfere with each other in the functional layers during diffraction, guaranteeing the full-color display clarity of the display system 300.

[0096] In some embodiments of this application, when the incident light is emitted from the image source 70, the red and blue light emitted from the image source 70 are circularly polarized light with the same chirality, and the red and green light emitted from the image source 70 are circularly polarized light with orthogonal chirality. Thus, combined with the polarization design of the first functional layer 35, the second functional layer 37, and the third functional layer 39 in the above embodiments, it can be ensured that the R, G, and B light do not interfere with each other in the functional layers during diffraction, guaranteeing the full-color display clarity of the display system 300.

[0097] It should be noted that in some embodiments of this application, the red and blue light emitted by the image source 70 can be circularly polarized with the same chirality, and the red and green light emitted by the image source 70 can be circularly polarized with orthogonal chirality, by means of multilayer dielectric film design, beam combining after polarization modulation of the three channels respectively, or pixel-level polarization modulation corresponding to the filter.

[0098] The first functional layer 35, the second functional layer 37, or the third functional layer 39 can be achieved by spin-coating and curing a liquid crystal layer on a substrate. The pitch of the liquid crystal material can be optimized according to the efficiency uniformity of the display device 100, and the film thickness can also be optimized according to the efficiency uniformity of the display device 100. Then, the three functional layers are stacked and pasted onto the planar component 10 or the waveguide plate 50 to form the polarizer holographic optical element 30 in the embodiment of this application.

[0099] Please see Figure 1 , Figure 2 , Figure 3 or Figure 4 and combined Figure 7 In some embodiments, the polarizer holographic optical element 30 further includes a substrate layer, and the first functional layer 35, the second functional layer 37 and the third functional layer 39 are stacked sequentially on the substrate layer.

[0100] For example, the substrate can be a flexible substrate or a non-flexible substrate. In the case of a flexible substrate, the functional layers (first functional layer 35, second functional layer 37, or third functional layer 39) can be directly fabricated on the flexible substrate, rather than obtained by peeling off an optically transparent adhesive film. The flexible substrate can be a polydimethylsiloxane film, a polymethyl methacrylate film, or other optical resin films. After fabricating the functional layers with a flexible substrate, the functional layers can be bonded to the housing using an optical UV adhesive with a refractive index matching.

[0101] In some embodiments, the first functional layer 35, the second functional layer 37, and the third functional layer 39 have the same thickness. This allows for continuous fabrication of each functional layer using the same process parameters (such as coating speed or blade gap), eliminating the need for frequent equipment adjustments or process configuration changes, significantly simplifying the fabrication process and improving production efficiency. It is understood that in other embodiments, at least two of the first functional layer 35, the second functional layer 37, and the third functional layer 39 have different thicknesses.

[0102] In this regard, please combine Figure 8 In some embodiments, two orthogonally circularly polarized beams (e.g., ...) can be used during the exposure process. Figure 8 The exposure light field is a linearly polarized light field with a specific polarization direction distribution, which is recorded by the light alignment layer. The surface shape of the freeform lens in the exposure light path can be obtained by reverse design of the desired F-PVH phase profile.

[0103] Please see Figure 2 In some embodiments of this application, the image source 70 can be either a collimated image source or a divergent image source. Specifically, when the image source 70 is a collimated image source, a polarizing grating 34 can be used as the input coupler; when the image source 70 is a divergent image source, a third polarizing holographic optical element can be used as the input coupler. In this case, the third polarizing holographic optical element is designed to diffract the light emitted from different pixels into parallel light propagating in different directions within the waveguide plate 50.

[0104] Secondly, please refer to Figure 9 and combined Figure 1 , Figure 2 , Figure 3 or Figure 4 This application provides a display system 300, which includes a light-transmitting display element 200 and a display device 100 as described in any of the above embodiments. It should be noted that the structure and characteristics of the light-transmitting display element 200 and the display device 100 in this embodiment are basically the same as those in the above embodiments, and will not be described in detail here.

[0105] The display system 300 can be a head-up display (HUD), which is an optoelectronic display device that projects information such as vehicle speed and navigation onto the driver's line of sight (usually located on the windshield) in an optical manner, forming a virtual image superimposed on the external road environment. In some embodiments of this application, the display system 300 can generate an information image through the image source 70, which is then magnified and imaged at a distance after reflection and diffraction by the polarizer holographic optical element 30. This allows the driver to obtain driving information while keeping their eyes on the road ahead, thereby reducing the time the driver's gaze deviates from the road and improving driving safety.

[0106] In the display system 300 of this application embodiment, the polarizer holographic optical element 30 is disposed on the target surface of the planar component 10, rather than on the light-transmitting display element 200 with a certain curvature. This prevents the polarizer holographic optical element 30 from wrinkling or deforming, thereby ensuring the final imaging effect and providing a better user experience. Furthermore, the polarizer holographic optical element 30 is adapted to diffract incident light onto the light-transmitting display element 200 (windshield), so that the light-transmitting display element 200 reflects the light from the polarizer holographic optical element 30 to a preset area A (eye box area). This allows the driver to see the road conditions ahead while also seeing the scene on the display screen, effectively reducing the time and frequency of the driver's observation of the instrument panel or GPS, and improving driving safety.

[0107] Thirdly, please refer to Figure 9 and combined Figure 1 , Figure 2 , Figure 3 or Figure 4 This application provides a vehicle 1000, which includes a display device 100 according to any of the above embodiments. The vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle, or a range-extended vehicle, etc., and is not limited in this application.

[0108] In the vehicle 1000 of this embodiment, the polarizer holographic optical element 30 is disposed on the target surface of the planar component 10, rather than on the light-transmitting display element 200 with a certain curvature. This prevents the polarizer holographic optical element 30 from wrinkling or deforming, thereby ensuring the final imaging effect and providing a better user experience. Furthermore, the polarizer holographic optical element 30 is adapted to diffract incident light onto the light-transmitting display element 200 (windshield), so that the light-transmitting display element 200 reflects the light from the polarizer holographic optical element 30 to a preset area A (eye box area). This allows the driver to see the road conditions ahead while also seeing the scene on the display screen, effectively reducing the time and frequency of the driver's observation of the instrument panel or GPS, and improving driving safety.

[0109] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as the combination of these technical features does not contradict each other, it should be considered within the scope of this specification. Furthermore, other embodiments can be derived from the above embodiments, allowing for structural and logical substitutions and changes without departing from the scope of this disclosure.

[0110] The embodiments described above are merely illustrative of several implementations of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. Therefore, the scope of protection of this patent application should be determined by the appended claims.

Claims

1. A display device (100), characterized in that, include: A planar component (10), wherein at least one target surface of the planar component (10) is configured as a plane, the target surface being adapted to be spaced apart from the light-transmitting display element (200); and A polarizing holographic optical element (30) is disposed on the target surface. The polarizing holographic optical element (30) is adapted to diffract incident light onto the light-transmitting display element (200) so that the light-transmitting display element (200) reflects the light from the polarizing holographic optical element (30) to a preset area.

2. The display device (100) according to claim 1, characterized in that, The planar component (10) includes a first target surface, and the polarizer holographic optical element (30) includes a first polarizer holographic optical element (31), which is disposed on the first target surface and is adapted to diffract incident light onto the light-transmitting display element (200); and / or, The planar component (10) includes multiple different target surfaces, and the polarizer holographic optical element (30) includes a first polarizer holographic optical element (31), which is disposed on one of the target surfaces. The incident light is adapted to be diffracted through the first polarizer holographic optical element (31) to the light-transmitting display element (200); and / or, The planar component (10) includes multiple different target surfaces, and the polarizing holographic optical element (30) includes multiple polarizing holographic optical elements respectively disposed on multiple different target surfaces. The incident light is adapted to be diffracted sequentially through multiple polarizing holographic optical elements to the light-transmitting display element (200).

3. The display device (100) according to claim 2, characterized in that, In the case where the planar component (10) includes multiple different target surfaces, the multiple different target surfaces can be constructed as a housing, at least one of the polarizer holographic optical elements (30) is disposed on the inner surface of the housing, and the light-transmitting display element (200) is adapted to be disposed on the outside of the housing.

4. The display device (100) according to claim 2, characterized in that, In the case where there are multiple polarizer holographic optical elements (30), at least two of the multiple polarizer holographic optical elements (30) have opposite grating vectors; and / or, All of the aforementioned polarizer holographic optical elements (30) are transmission-type elements; and / or, All of the aforementioned polarizer holographic optical elements (30) are reflective elements; and / or, Some of the multiple polarizer holographic optical elements (30) are transmission-type elements, and the other part is a reflection-type element.

5. The display device (100) according to claim 2, characterized in that, When multiple polarizer holographic optical elements (30) are included, the polarization selectivity of the multiple polarizer holographic optical elements (30) is the same; Each of the aforementioned polarizing holographic optical elements (30) diffracts right-handed circularly polarized light; or, The multiple polarizer holographic optical elements (30) all diffract left-handed circularly polarized light.

6. The display device (100) according to claim 1, characterized in that, The display device (100) further includes: Polarizing grating (34); A waveguide plate (50) has an input end (51) and an output end (53). The polarizer grating (34) is disposed at the input end (51) and is adapted to couple light into the waveguide plate (50). The polarizer holographic optical element (30) diffracts the light coupled out of the waveguide plate (50) to the light-transmitting display element (200).

7. The display device (100) according to claim 6, characterized in that, The polarizer holographic optical element (30) includes a transmissive element and at least one reflective element. The transmissive element is disposed at the coupling end (53) of the waveguide plate (50) and is adapted to transmit light coupled out of the waveguide plate (50) to the reflective element. The reflective element is adapted to reflect light from the transmissive element to the light-transmitting display element (200). And / or, the polarizer holographic optical element (30) includes at least two reflective elements, the reflective element disposed at the coupling end (53) of the waveguide plate (50) is adapted to reflect the light coupled out of the waveguide plate (50) to the remaining reflective elements, and the remaining reflective elements are adapted to reflect the light to the light-transmitting display element (200).

8. The display device (100) according to any one of claims 1-7, characterized in that, The polarizer holographic optical element (30) includes a first functional layer (35), a second functional layer (37), and a third functional layer (39), which are stacked sequentially. The second functional layer (37) is a first chiral cholesteric liquid crystal material, and the first functional layer (35) and the third functional layer (39) are second chiral cholesteric liquid crystals; and / or, The first functional layer (35) is adapted to diffract a first color of light, the second functional layer (37) is adapted to diffract a second color of light, and the third functional layer (39) is adapted to diffract a third color of light.

9. The display device (100) according to claim 8, characterized in that, The polarizer holographic optical element (30) further includes a substrate layer, and the first functional layer (35), the second functional layer (37) and the third functional layer (39) are stacked sequentially on the substrate layer.

10. The display device (100) according to claim 8, characterized in that, The first and third colors in the incident light are circularly polarized with the same chirality, the first and second colors in the incident light are circularly polarized with cross-chirality, and the third and second colors in the incident light are circularly polarized with cross-chirality.

11. A display system (300), characterized in that, include: Transparent display element (200); and The display device (100) according to any one of claims 1-10.

12. The display system (300) according to claim 11, characterized in that, At least a portion of the light-transmitting display element (200) is a surface with a preset curvature.

13. The display system (300) according to claim 11, characterized in that, The display system (300) also includes: An image source (70) is provided at an interval from the polarizer holographic optical element (30) and is used to emit the incident light toward the polarizer holographic optical element (30).

14. A vehicle (1000), characterized in that, include: The display device (100) according to any one of claims 1-10, or, The display system (300) according to any one of claims 11-13.

15. The vehicle (1000) according to claim 14, characterized in that, The light-transmitting display element (200) includes at least the windshield of the vehicle.

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