Internal projection suspension HUD system

Abstract

The invention provides an internal projection suspension HUD system, and the system comprises an image source which is used for emitting a light beam; the reflection imaging assembly is used for directly receiving the light beam emitted by the image source and reflecting the light beam to project a real image; and the one-way perspective film is arranged at the position of the real image so as to enable the real image to realize a suspension effect. Compared with an HUD system adopting virtual image imaging in the prior art, the HUD system has the advantages that the light beam is directly received through the reflection imaging assembly, and the light beam is reflected so as to directly project a real image; furthermore, a one-way perspective film 4 is further arranged at the real image position, one side of the one-way perspective film 4 can be perspective, the other side of the one-way perspective film 4 has reflectivity, and by arranging the one-way perspective film 4 at the real image position, the viewer can clearly see the real image from the viewing side of the one-way perspective film 4; however, the scene behind the one-way perspective film 4 cannot enter the eyes of the viewer through the one-way perspective film 4, so that a real image suspension effect from the viewing angle of the viewer is achieved.

Description

Technical Field

[0001] The present application relates to the field of head-up display technology, and in particular to an internally projected suspended HUD system. Background Art

[0002] The existing head-up display (HUD) systems all use virtual image imaging, that is, the virtual image is formed at different distances of 2.5m to 7.5m in front of the vehicle for the driver to look up and observe. However, in actual use, it is found that the virtual image imaging distance is far and is located outside the last reflector (or windshield), lacking three-dimensional and layered sense, the user's visual viewing experience is not good, and the virtual image cannot be reused, resulting in limited usage scenarios. Summary of the invention

[0003] Based on the above situation, the main purpose of the present invention is to provide an internally projected floating HUD system, aiming to solve the technical problems in the prior art that the head-up display system is a virtual image with a long imaging distance and is located outside the last reflector (or windshield), lacks a sense of three-dimensionality and layering, and the user's visual viewing experience is poor, and the virtual image cannot be reused, resulting in limited usage scenarios.

[0004] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0005] A first aspect of an embodiment of the present invention provides an internally projected suspended HUD system, comprising an image source, a reflective imaging component and a one-way perspective film; wherein:

[0006] The image source is used to emit a light beam;

[0007] The reflective imaging component is used to directly receive the light beam emitted by the image source and reflect the light beam to project a real image;

[0008] The one-way perspective film is arranged at the real image position so as to enable the real image to achieve a suspension effect.

[0009] Optionally, an eye box is provided at a set distance from the one-way perspective film, and the real image is suitable for entering a human eye through the eye box.

[0010] Optionally, the one-way perspective film is made of a polymer film or glass, and the film surface of the one-way perspective film has a microstructure.

[0011] Optionally, the one-way vision film comprises a substrate and a multi-layer optical coating and an abrasion-resistant coating sequentially coated on the surface of the substrate.

[0012] Optionally, the multilayer optical coating comprises a first coating, a second coating and a third coating, wherein the first coating is a low refractive index layer coated on the surface of the substrate, the second coating is a high refractive index layer coated on the surface of the first coating, and the third coating is a low refractive index layer coated on the surface of the second coating.

[0013] Optionally, the substrate is glass or plastic, and the refractive index n is 1.5; the first coating, the second coating and the third coating are all silicon dioxide layers, wherein the refractive index n of the first coating is 1.46, and the thickness is 100nm; the refractive index n of the second coating is 2.4, and the thickness is 50nm; the refractive index n of the third coating is 1.46, and the thickness is 100nm.

[0014] Optionally, the performance index P of the HUD system is obtained by the following formula:

[0015]

[0016] Where, T represents the transmittance of the one-way perspective film, R represents the reflectivity of the one-way perspective film, and A max represents the maximum viewing angle of the one-way perspective film, C represents the real image color restoration of the one-way perspective film, U represents the light transmittance uniformity of the one-way perspective film, V represents the volume of the one-way perspective film, I represents the real image imaging effect, and W T , W R , W C , W U , W V , W I Used to indicate the weight of the above indicators.

[0017] Optionally, the reflective imaging component includes a first reflector, a second reflector and a third reflector for reflecting the light beam, at least one of the first reflector, the second reflector and the third reflector is also used to converge the light beam, the first reflector is located in the light emitting direction of the image source, the second reflector is located in the light beam reflection direction of the first reflector, the third reflector is located in the light beam reflection direction of the second reflector, and at the same time, the second reflector is also located in the light beam reflection direction of the third reflector, the light beam emitted by the image source is reflected by the first reflector and the second reflector, the light beam reflected by the second reflector is directed to the third reflector and reflected by the third reflector and then directed back to the second reflector, and finally the light beam is directed to the one-way perspective film by the second reflector, and during the reflection process of the light beam, at least one of the first reflector, the second reflector and the third reflector converges the light beam so that the light beam emitted by the second reflector forms the real image at the one-way perspective film.

[0018] Optionally, the surface formulas of the first reflector, the second reflector, and the third reflector are:

[0019]

[0020] Among them, r 2 =x 2 +y 2 , z represents the sagittal height difference in the Z-axis direction, c represents the curvature, k represents the conic surface constant, and m and n represent the orders of x and y respectively.

[0021] Optionally, the one-way perspective film is located at the vehicle's onboard instrument panel and / or central control display screen.

[0022] Beneficial effects:

[0023] An internally projected suspended HUD system provided in an embodiment of the present invention includes an image source, a reflective imaging component and a one-way perspective film 4, wherein the image source is used to emit a light beam, the reflective imaging component is used to directly receive the light beam emitted by the image source and reflect the light beam to project a real image, and the one-way perspective film 4 is arranged at the real image position to enable the real image to achieve a suspended effect.

[0024] First, compared with the virtual image imaging adopted in the HUD system of the prior art, the embodiment of the present invention directly receives the light beam through the reflective imaging component, and reflects the light beam to directly project the real image. The real image can provide the viewer with a closer visual experience. The real image is imaged at a close distance, and can produce a shallow depth of field effect similar to close-up photography, so that the background of the presented image is blurred, thereby highlighting the subject and making the presented image more three-dimensional, layered and artistic. Furthermore, the embodiment of the present invention is also provided with a one-way perspective film 4 at the real image position. The one-way perspective film 4 can realize perspective on one side and reflective on the other side. By providing the one-way perspective film 4 at the real image position, the viewer can clearly see the real image from the side he is viewing, but the scene behind the one-way perspective film 4 cannot enter the viewer's eyes through the one-way perspective film 4, thereby achieving a real image suspension effect from the viewer's perspective.

[0025] Secondly, the reflective imaging assembly of the embodiment of the present invention is configured to directly receive the light beam emitted by the image source, which has a simpler structure than entering the imaging optical assembly through an optical shaping element (such as a collimating optical element).

[0026] Thirdly, the present invention adopts a lightweight design of a reflective structure, which only includes an image source, a reflective imaging component and a one-way perspective film 4 to achieve a real image and a real image suspension effect. It has a simple and compact structure and a small size, which not only saves costs but is also easy to assemble.

[0027] Other beneficial effects of the present invention will be explained in the specific implementation manner through the introduction of specific technical features and technical solutions. Through the introduction of these technical features and technical solutions, those skilled in the art should be able to understand the beneficial technical effects brought about by the technical features and technical solutions. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The preferred embodiments of the internal projection suspension HUD system of the present invention will be described below with reference to the accompanying drawings.

[0029] In the figure:

[0030] Figure 1 A schematic diagram of an optical path design of an internally projected suspended HUD system according to a preferred embodiment of the present invention;

[0031] Figure 2 yes Figure 1 Schematic diagram of the structure of the internal projection suspension HUD system;

[0032] Figure 3 yes Figure 1 Schematic diagram of the optical path design of the internal projection suspension HUD system;

[0033] Figure 4 This is a schematic diagram of an optical path design of an internally projected suspended HUD system according to another preferred embodiment of the present invention;

[0034] Figure 5 This is a schematic diagram of an optical path design of an internally projected suspended HUD system according to a preferred embodiment of the present invention, in which the optical path does not pass through a windshield;

[0035] Figure 6 It is a schematic diagram of the optical path design of the internal projection floating HUD system passing through the windshield according to a preferred embodiment of the present invention.

[0036] Reference numerals:

[0037] 1. Image source; 2. Reflective imaging component; 21. First reflector; 22. Second reflector; 23. Third reflector; 3. Light beam; 4. One-way perspective film; 5. Eye box; 6. Windshield. DETAILED DESCRIPTION

[0038] The present invention is described below based on embodiments, but the present invention is not limited to these embodiments. In the following detailed description of the present invention, some specific details are described in detail. In order to avoid confusing the essence of the present invention, known methods, processes, procedures, and components are not described in detail.

[0039] In addition, persons of ordinary skill in the art will appreciate that the drawings provided herein are for illustration purposes and are not necessarily drawn to scale.

[0040] Unless the context clearly requires otherwise, throughout the specification and claims, the words "include", "comprising" and similar words should be interpreted in an inclusive sense rather than an exclusive or exhaustive sense; that is, in the sense of "including but not limited to".

[0041] In the description of the present invention, it should be understood that the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0042] Before introducing the specific implementation of the present invention, some of the terms used herein are explained. It should be noted that these explanations are for the purpose of facilitating the understanding of those skilled in the art, and are not intended to limit the scope of protection claimed by the present invention.

[0043] Here are some explanations of the terms used in this article:

[0044] HUD system: The HUD (Head Up Display) system, also known as the head-up display system, is a technology that projects important information onto the driver's windshield, designed to help the driver obtain key driving information without lowering or turning his head. It should be noted that in this article, the projection position of the image is no longer limited to projecting the image onto the driver's windshield. In some usage scenarios, the projection of the image does not rely on the windshield. The optical principle of the HUD system is based on the reflection and / or refraction of light. Its basic structure includes a light source, a reflector, and a transparent display screen. The light emitted by the light source is reflected by the reflector to form a virtual image. This image is projected onto the transparent display screen and then reflected back into the driver's eyes. Since this image looks like it is in front of the driver, it can reduce the driver's line of sight and improve driving safety. The optical principle of the HUD system also involves the visual principle of the human eye. The human eye can see objects because the light reflected or emitted by the object enters the human eye. When the light enters the human eye, it is refracted by the lens and vitreous body, and then forms an inverted real image on the retina. The photoreceptor cells on the retina convert light signals into electrical signals, which are then transmitted to the brain through the optic nerve, ultimately forming the image we see. In the HUD system, the image on the display screen is reflected and enters the driver's eyes. Since this image has been reflected twice, it forms an inverted virtual image on the retina. However, due to the visual adaptability of the human eye, we can still see an upright image. In short, the optical principle of the HUD head-up display system is based on the reflection and refraction of light and the visual principle of the human eye. It reduces the driver's line of sight diversion and improves driving safety by projecting a virtual image onto a transparent display screen and then reflecting it back into the driver's eyes.

[0045] Eye box: In the HUD head-up display system, the eye box refers to the area where the eyes can move, that is, the position range of the driver's eyes. The size and position of this area are affected by factors such as the driver's height, sitting posture, and head position, resulting in different driving perspectives for each person. The concept of the eye box is very important in HUD design because it is directly related to whether the driver can clearly see the information displayed by the HUD. If the eyes are located in the eye box area, the entire image can be seen clearly; conversely, if they are out of this area, the entire image cannot be seen. Therefore, the design of the HUD needs to take into account the eye box position of different drivers to ensure the effective display of information.

[0046] Real image and virtual image: In the HUD head-up display system, the distinction between real image and virtual image is mainly based on the imaging principle and observation method. The real image is an image formed by the convergence of actual light and can be presented on the light screen. In the HUD system, the real image usually refers to the image formed by the actual convergence of lenses or other optical elements. This image can be directly observed by adjusting the position because it does exist in a certain physical position. The virtual image is an image formed by the intersection of the reverse extension lines of the actual light and cannot be presented on the light screen. In the HUD system, the virtual image usually refers to the image formed by reflection or refraction by plane mirrors or other optical elements. Although these images are not directly formed by actual light, through the design of the optical system, the driver can observe these images without moving his eyes because they are actually formed by the intersection of the extension lines of the light path.

[0047] Image source: Also known as the picture generation unit (PGU), the image source is one of the core components of the HUD head-up display system, which is responsible for generating images. In the HUD system, the image source generates light sources, which are magnified and projected onto the driver's eye activity area, so that important driving information such as speed and navigation can be projected onto the driver's front windshield, allowing the driver to obtain driving information without lowering or turning his head. This design helps improve driving safety.

[0048] In related technologies, HUD systems all use virtual image imaging, that is, the virtual image is formed at different distances of 2.5m to 7.5m in front of the vehicle for the driver to look up and observe. However, in actual use, it is found that the virtual image imaging distance is far and is located outside the last reflector (or windshield), which cannot achieve a shallow depth of field effect, and the user's visual viewing experience is poor.

[0049] To do this, refer to Figures 1 to 6 The embodiment of the present invention provides an internal projection suspension HUD system, comprising an image source 1, a reflective imaging component 2 and a one-way perspective film 4. The image source 1 is used to emit a light beam 3, the reflective imaging component 2 is used to reflect and image the light beam 3, the reflective imaging component 2 is arranged on the propagation path of the light beam 3 emitted by the image source 1, the reflective imaging component 2 is arranged to directly receive the light beam 3 emitted by the image source 1 and fold the light path of the light beam 3, and reflect the light beam 3 to the one-way perspective film 4 to converge into a real image. The one-way perspective film 4 is arranged at the real image position, so that the reflective imaging component 2 directly projects a real image on the one-way perspective film 4. Due to the characteristics of the one-way perspective film 4 itself (one side is transparent and the other side is not transparent), when the one-way perspective film 4 is transparent to the viewer, the viewer can see a clear real image from the side he is watching, and the scene behind the one-way perspective film 4 (such as the structure inside the car, etc.) cannot enter the human eye through the one-way perspective film 4, so that the viewer can observe a real image showing a suspension effect.

[0050] More specifically, in the embodiment of the present invention, the image source 1 generates a light source to emit a light beam 3 carrying image information, and the image information may be, for example, vehicle instrument panel information and / or central control display screen image information, which is not limited by the present invention. The light beam 3 of the image source 1 is emitted in a direction toward the reflective imaging component 2. The light beam 3 is emitted by the image source 1 and enters the reflective imaging component 2. The reflective imaging component 2 adjusts the propagation direction and then emits the light beam, which converges into a real image on the one-way perspective film 4.

[0051] The reflective imaging component 2 is used to fold the optical path of the light beam 3. In the embodiment of the present invention, the optical path folding refers to designing a system using the reflective imaging component 2 to avoid introducing chromatic aberration so as to realize the reflection and display of the image in a limited optical path space. The reflective imaging component 2 is arranged in the propagation direction of the light beam 3 emitted by the image source 1. The reflective imaging component 2 is further arranged to directly receive the light beam 3 emitted by the image source 1, that is, the light beam 3 does not pass through any light beam 3 shaping element from the image source 1 to the reflection imaging component 2. The reflective imaging element realizes the optical path folding of the light beam 3 by reflecting the light beam 3. By designing the reflective imaging component 2, the light beam 3 reflected from the reflective imaging component 2 can be converged into a real image at the one-way perspective film 4.

[0052] Compared with the virtual image imaging adopted by the HUD system of the related art, firstly, the embodiment of the present invention directly receives the light beam through the reflective imaging component, and reflects the light beam to directly project the real image, and the real image can provide the viewer with a closer visual experience of imaging. The real image is imaged at a close distance, and can produce a shallow depth of field effect similar to close-up photography, so that the background of the presented image is blurred, thereby highlighting the subject, and making the presented image more three-dimensional, layered and artistic; further, the embodiment of the present invention is also provided with a one-way perspective film 4 at the real image position, and the one-way perspective film 4 can realize perspective on one side, while the other side is reflective. By providing the one-way perspective film 4 at the real image position, the viewer can clearly see the real image from the side he is watching, but the scene behind the one-way perspective film 4 cannot enter the viewer's eyes through the one-way perspective film 4, thereby achieving a real image suspension effect from the viewer's perspective. Secondly, the reflective imaging component 2 of the embodiment of the present invention is configured to directly receive the light beam 3 emitted by the image source 1, and the structure is simpler than entering the imaging optical component through an optical shaping element such as a collimating optical element. Furthermore, the embodiment of the present invention adopts a lightweight design of a reflective structure, which only includes an image source, a reflective imaging component and a one-way perspective film 4 to achieve a real image and a real image suspension effect. It has a simple and compact structure and a small size, which not only saves costs but is also easy to assemble.

[0053] In some implementations of the embodiments of the present invention, there is no need to design an eye box. Since the suspended real image achieved by the one-way perspective film 4 also has a large viewing angle, even without designing an eye box, the viewer can still view the suspended real image from a larger viewing angle.

[0054] In some other implementations of the embodiments of the present invention, an eye box is designed. When the eye box is designed, the viewer observes the suspended real image within the range of the eye box.

[0055] In the HUD system, in order to achieve a better suspension effect, the material selection of the one-way perspective film 4 is crucial. In the embodiment of the present invention, a polymer film or glass is selected, which can provide higher light transmittance and reasonable reflection properties.

[0056] In order to further optimize the reflectivity and transmittance, in this embodiment, the one-way perspective film 4 includes a substrate and a multilayer optical coating, an anti-reflective coating and an abrasion-resistant coating sequentially coated on the surface of the substrate. Among them, the multilayer optical coating uses physical vapor deposition (PVD), chemical vapor deposition (CVD) or sputtering deposition technology to deposit layered materials on the surface of the film. These layers can alternately use materials with different refractive indices (such as SiO2, TiO2) to achieve the desired optical properties. The above multilayer coating technology belongs to the prior art and will not be repeated here. A wear-resistant coating is also coated on the multilayer optical coating. By coating the wear-resistant coating, the wear resistance and scratch resistance of the film surface can be improved to ensure that the optical properties remain unchanged during long-term use.

[0057] Furthermore, in the design of the multilayer optical coating, it is designed as an anti-reflective coating to improve the optical performance. The multilayer optical coating (anti-reflective coating) includes a first coating, a second coating and a third coating, wherein the first coating is a low refractive index layer coated on the surface of the substrate, the second coating is a high refractive index layer coated on the surface of the first coating, and the third coating is a low refractive index layer coated on the surface of the second coating.

[0058] Further, in the multilayer optical coating design, as an example, the transmittance is suitable for the visible light range (400-700nm).

[0059] Substrate: The material is glass (or plastic), the refractive index n is 1.5, and the thickness is set according to actual application requirements.

[0060] First coating (low refractive index layer): the material is silicon dioxide (SiO2), the refractive index n is 1.46, and the thickness is 100nm (optimizing the anti-reflection effect).

[0061] Second coating (high refractive index layer): the material is silicon dioxide (SiO2), the refractive index n is 2.4, and the thickness is 50nm (the high refractive index layer increases the interference effect).

[0062] The third coating layer (low refractive index layer): the material is silicon dioxide (SiO2), the refractive index n is 1.46, and the thickness is 100nm (as the upper layer of the second coating layer, continuing to optimize the transmittance).

[0063] As described above, by alternately combining low refractive index layers and high refractive index layers, the interference effect of light is utilized to reduce reflection and increase transmittance.

[0064] When designing the internal projection suspended HUD system, factors such as the transmittance, reflectivity, viewing angle, color reproduction, uniformity of light transmission, volume, and actual imaging effect of the one-way perspective film 4 need to be considered, so it is a complex design process.

[0065] In order to simplify the design, the applicant integrated the above indicators and proposed a performance indicator P for evaluating the internal projection suspension HUD system based on years of industry experience.

[0066] The light transmittance T of the one-way perspective film 4 is obtained by the following formula:

[0067]

[0068] Among them, I 透 is the light intensity passing through the one-way perspective film 4, I 入 is the intensity of the incident light.

[0069] The reflectivity R of the one-way perspective film 4 is obtained by the following formula:

[0070]

[0071] Among them, I 反射 is the intensity of light reflected from the film surface.

[0072] The viewing angle A of the one-way perspective film 4 is obtained by the following formula:

[0073] A=θ max

[0074] Among them, θ max The maximum viewing angle.

[0075] The color reproduction C of the one-way vision film 4 is obtained by the following formula:

[0076]

[0077] Among them, C 原 is the original color value, C 观 is the color value when viewed, and n is the number of colors.

[0078] The light transmittance uniformity U of the one-way perspective film 4 is obtained by the following formula:

[0079]

[0080] Among them, σ is the standard deviation of transmittance, and μ is the mean of transmittance.

[0081] The volume V of the one-way perspective film 4 is obtained by the following formula:

[0082] V=A 横 *d

[0083] Among them, A 横 is the cross-sectional area and d is the thickness.

[0084] The real image effect I of the one-way perspective film 4 is obtained by the following formula:

[0085]

[0086] Among them, C 清晰度 is the fraction of actual imaging clarity, C 最大 is the maximum possible clarity score (e.g., 10 points).

[0087] Taking the above considerations into account, the performance index P of the HUD system in the embodiment of the present invention is obtained by the following formula:

[0088]

[0089] Wherein, T represents the transmittance of the one-way perspective film 4, R represents the reflectivity of the one-way perspective film 4, and A max represents the maximum viewing angle of the one-way perspective film 4, C represents the real image color restoration degree of the one-way perspective film 4, U represents the light transmittance uniformity of the one-way perspective film 4, V represents the volume of the one-way perspective film 4, I represents the real image imaging effect, and W T , W R , W C , W U , W V , W I Used to indicate the weight of the above indicators.

[0090] As a specific example, assume that the calculation results of each index are as follows: T = 0.85 (transmittance), R = 0.1 (reflectivity), A = 40° (viewing angle), C = 0.9 (color reproduction), U = 0.95 (transmittance uniformity), V = 0.005m 3 (volume), I = 0.8 (imaging effect);

[0091] Set the weights as follows: W T =0.2,W R =0.15,W A =0.1,W C =0.15,WU =0.15,W V =0.1,W I =0.15;

[0092] Calculation performance index P:

[0093]

[0094] The above calculations result in a performance index P that is synthesized from each individual index. The higher the value, the better the product performance. Through detailed formula calculation, this performance evaluation is more rigorous and it is easy to compare the advantages and disadvantages of different products.

[0095] In some implementations of the internal projection suspension HUD system of the embodiment of the present invention, such as Figures 1 to 3 As shown, the reflective imaging component 2 includes a first reflector 21 and a second reflector 22 for reflecting the light beam 3, at least one of the first reflector 21 and the second reflector 22 is also used to converge the light beam 3, the first reflector 21 is located in the light emitting direction of the image source 1, and the second reflector 22 is located in the reflection direction of the light beam 3 of the first reflector 21, the light beam 3 emitted by the image source 1 is reflected and converged by the first reflector 21 and the second reflector 22, and the light beam 3 is emitted by the second reflector 22 to form the real image at the one-way perspective film 4.

[0096] In some possible implementation schemes under this embodiment, the first reflector 21 is used as a secondary mirror, and can be a plane mirror, a curved mirror, a spherical mirror, an aspherical mirror or a free-curved mirror, and is set to only reflect the light beam 3. The second reflector 22 is used as a primary mirror, and can be a curved mirror, a spherical mirror, an aspherical mirror or a free-curved mirror, and is set to reflect and converge the light beam 3. When in use, the light beam 3 emitted by the image source 1 first enters the first reflector 21, and then enters the second reflector 22 after being reflected by the first reflector 21. The second reflector 22 reflects and converges the light beam 3 and then emits the light beam 3 to the one-way perspective film 4 to form a real image. It should be noted that the present invention does not make any special restrictions on this. In other possible implementation schemes, the first reflector 21 can also be used to reflect and converge the light beam 3, and the second reflector 22 is only used to reflect the light beam 3, as long as a real image can be formed on the one-way perspective film 4 after reflection and convergence by the first reflector 21 and the second reflector 22.

[0097] The HUD system can directly form a real image in the one-way perspective film 4 by reflecting and converging the light beam 3 by the first reflector 21 and the second reflector 22. The reflective imaging component 2 only includes the first reflector 21 and the second reflector 22, has a simple structure, a small volume, a wide range of application scenarios and a low cost.

[0098] The present invention is not limited to the reflective imaging component 2 comprising only two reflectors. In other implementations of the projection suspension HUD system of the present invention, for example, Figure 4 As shown, the reflective imaging assembly 2 includes a first reflector 21, a second reflector 22 and a third reflector 23 for reflecting a light beam 3. At least one of the first reflector 21, the second reflector 22 and the third reflector 23 is also used to converge the light beam 3. The first reflector 21 is located in the light emitting direction of the image source 1, the second reflector 22 is located in the light beam 3 reflecting direction of the first reflector 21, and the third reflector 23 is located in the light beam 3 reflecting direction of the second reflector 22. At the same time, the second reflector 22 is also located in the light beam 3 reflecting direction of the third reflector 23. The image source 1 emits The light beam 3 is reflected by the first reflector 21 and the second reflector 22, the light beam 3 reflected by the second reflector 22 is directed to the third reflector 23 and reflected by the third reflector 23 and then directed back to the second reflector 22, and finally the light beam 3 is directed to the one-way perspective film 4 by the second reflector 22. During the reflection process of the light beam 3, at least one of the first reflector 21, the second reflector 22 and the third reflector 23 converges the light beam 3 so that the light beam 3 emitted by the second reflector 22 forms the real image at the one-way perspective film 4.

[0099] In some possible implementation schemes under this embodiment, the first reflector 21 can be a plane mirror, a curved mirror, a spherical mirror, an aspherical mirror or a free-curved mirror, and is configured to reflect the light beam 3 only. The second reflector 22 can be a curved mirror, a spherical mirror, an aspherical mirror or a free-curved mirror, and is configured to reflect and converge the light beam 3. The third reflector 23 can be a plane mirror, a curved mirror, a spherical mirror, an aspherical mirror or a free-curved mirror, and is configured to reflect the light beam 3. When in use, the light beam 3 emitted by the image source 1 first enters the first reflector 21, and then enters the second reflector 22 after being reflected by the first reflector 21. The second reflector 22 reflects the light beam 3 and then enters the third reflector 23. After the third reflector 23 reflects the light beam 3, the light beam 3 is re-emitted back to the second reflector 22. The second reflector 22 further reflects and converges the light beam 3, and the light beam 3 emitted from the second reflector 22 enters the one-way perspective film 4 to form a real image. Similarly, the present invention is not limited to the above-mentioned implementation scheme. It can be understood that in other possible implementation schemes, the first reflector 21 and the third reflector 23 can also be used to reflect and converge the light beam 3, as long as a real image can be formed at the one-way perspective film 4 after reflection and convergence by the first reflector 21, the second reflector 22 and the third reflector 23.

[0100] Compared with two reflectors, the reflective imaging assembly 2 composed of three reflectors is used. By adding a reflector, the design variables are increased, and it is easier to design a good imaging effect. The light beam 3 reflected by the second reflector 22 is directed to the third reflector 23 and reflected by the third reflector 23 and then directed back to the second reflector 22. Finally, the second reflector 22 directs the light beam 3 to the one-way perspective film 4. This design can save space and reduce the volume of the reflective imaging assembly 2. One reflector (the second reflector 22) performs two reflections. Without increasing the total number of lenses, the number of design variables is increased, the design difficulty is reduced, and the overall volume can be kept small.

[0101] In some other implementations of the internal projection suspension HUD system of the embodiment of the present invention, the image source 1 includes a first light emitting area and a second light emitting area, the first light emitting area is used to emit a first light beam 3, and the second light emitting area is used to emit a second light beam 3; the reflective imaging component 2 includes a first reflector 21 and a second reflector 22, the first reflector 21 has a first reflective area and a second reflective area, and the second reflector 22 has a third reflective area and a fourth reflective area.

[0102] When in use, the first light emitting area emits a first light beam 3, which enters the first reflection area of ​​the first reflector 21, and after being reflected by the first reflection area, enters the third reflection area of ​​the second reflector 22, and after being reflected by the third reflection area, the light beam 3 is emitted to the first target position in the one-way perspective film 4 to form a first real image. The second light emitting area emits a second light beam 3, which enters the second reflection area of ​​the first reflector 21, and after being reflected by the second reflection area, enters the fourth reflection area of ​​the second reflector 22, and after being reflected by the fourth reflection area, the light beam 3 is emitted to the second target position in the one-way perspective film 4 to form a second real image.

[0103] Through the internal projection suspended HUD system of this embodiment, two real images are achieved only through the reflective structure. On the one hand, the richness of the image is further increased. On the other hand, by partitioning the image source 1 and the reflector, two real images can be achieved through a set of image source 1 and a set of reflective structure.

[0104] Further, in some preferred implementation schemes under this embodiment, the first reflection area and the second reflection area of ​​the first reflector 21 are adjacent and do not overlap, and the third reflection area and the fourth reflection area of ​​the second reflector 22 are adjacent and do not overlap. The projection areas of the first light beam 3 and the second light beam 3 on the first reflector 21 and the second reflector 22 are adjacent and do not overlap.

[0105] In some other preferred implementation schemes under this embodiment, the first reflection area and the second reflection area of ​​the first reflector 21 partially overlap, and the third reflection area and the fourth reflection area of ​​the second reflector 22 do not overlap. In this way, the projection areas of the first light beam 3 and the second light beam 3 on the first reflection area and the second reflection area partially overlap, and after being reflected by the first reflection area and the second reflection area respectively, the projection areas on the third reflection area and the fourth reflection area are separated, that is, the optical paths of the first light beam 3 and the second light beam 3 are separated in the third reflection area and the fourth reflection area of ​​the second reflector 22. The first light beam 3 and the second light beam 3 form a first real image and a second real image in the one-way perspective film 4 after being reflected by the third reflection area and the fourth reflection area respectively. In this embodiment, the reflection area of ​​the first reflector 21 can be reduced, which is conducive to reducing the overall volume and facilitating application.

[0106] In this embodiment, there may be some possible implementation schemes, for example, the first reflection area and the second reflection area partially overlap, and the third reflection area and the fourth reflection area partially overlap.

[0107] In addition, in a preferred embodiment of the present invention, the first real image and the second real image are fused within the driver's eye box 5. Image fusion can bring better imaging effects and user experience.

[0108] The light beam 3 of the HUD system of the embodiment of the present invention may not pass through the windshield 6. Figure 5 As shown, the light beam 3 emitted by the image source 1 is reflected and converged by the reflective imaging component 2 to directly form a real image on the one-way perspective film 4.

[0109] The light beam 3 of the HUD system of the embodiment of the present invention may also pass through the windshield 6, such as Figure 6 As shown, in some embodiments, the reflective imaging assembly 2 includes a first reflector 21 and a second reflector 22 for reflecting the light beam 3, at least one of the first reflector 21 and the second reflector 22 is also used to converge the light beam 3, the first reflector 21 is located in the light emitting direction of the image source 1, the second reflector 22 is located in the reflection direction of the light beam 3 of the first reflector 21, and the reflection direction of the light beam 3 of the second reflector 22 points to the windshield 6, the light beam 3 emitted by the image source 1 is reflected and converged by the first reflector 21 and the second reflector 22, and then the light beam 3 is emitted by the second reflector 22 to the concave surface of the windshield 6, and the concave surface of the windshield 6 reflects the light beam 3 to the one-way perspective film 4 to form the real image. Compared with the reflective imaging assembly 2 directly imaging on the one-way perspective film 4, the embodiment of the present invention utilizes the original windshield 6 on the vehicle, which is equivalent to further increasing the number of reflective lenses, increasing design variables, and can further reduce the design difficulty without increasing the volume.

[0110] Further, in the embodiment of the present invention, the first reflector 21, the second reflector 22 and the third reflector 23 are all free-form surface mirrors, and the surface shapes of the first reflector 21, the second reflector 22 and the third reflector 23 are obtained by the following formula:

[0111]

[0112] Among them, r 2 =x 2 +y 2 , z represents the sagittal height difference in the Z-axis direction, c represents the curvature, k represents the conic surface constant, and m and n represent the orders of x and y respectively.

[0113] From a design perspective, an important parameter is the magnification, which is the ratio of the real image area to the luminous area of ​​the image source 1. The magnification determines the difficulty of the design. The higher the magnification, the greater the difficulty of the design. In an embodiment of the present invention, the ratio of the real image area to the luminous area of ​​the image source 1 is 1.5-2.5, preferably 2.

[0114] In actual use, if the real image is not clear enough, the image clarity can be adjusted by adjusting the size of the image source 1, the first reflector 21, and the second reflector 22, and the position and angle of the image source 1, the first reflector 21, and the second reflector 22. Figure 1 According to the above-mentioned surface calculation formula of the first reflector 21 and the second reflector 22, and the value of the magnification, the embodiment of the present invention proposes a set of preferred parameters, wherein the size of the image source 1 is: 50mm*25mm; the specific parameters of the first reflector 21 and the second reflector 22 are: the length of the large mirror of the second reflector 22 is 160mm, and the width is 120mm; the length of the small mirror of the first reflector 21 is 100mm, and the width is 70mm; the distance from the real image to the second reflector 22 is 500mm±20mm, and the distance from the real image to the eye box 5 is 550±20mm; the distance between the second reflector 22 and the first reflector 21 is 250mm±20mm; the distance from the first reflector 21 to the image source 1 is 270mm±20mm; the focal length of the second reflector 22 is 400mm-500mm, the focal length of the first reflector 21 is 260mm-360mm, the second reflector 22 is deflected 10-20° around the X-axis (X in zemax is the positive direction of X inward from the paper), and the first reflector 21 is deflected 15-25° around the X-axis; assuming that the image source 1 is incident, the angle of the incident light beam 3 is 5.5°×5.5°, the outgoing light beam 3 forms a real image size of about 100mm*50mm, and the angle observed from the eye box 5 is about 10°*5°.

[0115] It should be noted that the set of parameters adopted in the above implementation is not the only solution, and different design results can be optimized according to actual needs.

[0116] For the embodiment in which the reflective imaging assembly 2 includes three reflectors, in actual use, if the real image is not clear enough, the image clarity can be adjusted by adjusting the size of the image source 1, the first reflector 21, the second reflector 22 and the third reflector 23, and the position and angle of the image source 1, the first reflector 21, the second reflector 22 and the third reflector 23. As an example, please refer to Figure 4 According to the surface calculation formulas of the first reflector 21, the second reflector 22 and the third reflector 23, as well as the value of the magnification, the embodiment of the present invention proposes a set of preferred parameters, wherein the real image size is 46mm*28mm; the image source 1 size is 40mm*20mm; the first reflector 21 size is 20mm±10mm*20mm±10mm; the second reflector 22 size is 100mm±10mm*84mm±10mm; the third reflector 23 size is 90mm±10mm*50mm±10mm; the distance from the real image to the eye box 5 is 520mm±50mm; the window is away from the real image: 60mm±10mm; the image source 1 is away from the first reflector 21: 40mm±10mm; the first reflector 21 is away from the second reflector 22: 50mm±10mm; the third reflector 23 is away from the first reflector 21: 45mm±10mm; the second reflector 22 is away from the window: 60mm±10mm. The image source 1 is an LCD, the first reflector 21 and the third reflector 23 are free-form surfaces, and the second reflector 22 is a plane mirror.

[0117] Through the above parameter settings, the embodiment of the present invention can obtain a clear and stable real image.

[0118] Furthermore, in the embodiment of the present invention, the one-way perspective film 4 is located at the position of the vehicle's onboard instrument and / or central control display screen. By setting the one-way perspective film 4 at the position of the vehicle's onboard instrument and / or central control display screen, the vehicle can omit the onboard instrument and / or central control display screen, that is, the original vehicle-mounted instrument and / or central control display screen of the vehicle is replaced by the one-way perspective film 4 and the real image, which can greatly simplify the structure, reduce costs, and increase the flexibility of system functions and the diversity of display effects compared to traditional vehicles.

[0119] An embodiment of the present invention further provides a vehicle, comprising the internally projected floating HUD system described in any one of the above embodiments.

[0120] It will be appreciated by those skilled in the art that, under the premise of no conflict, the above-mentioned preferred solutions can be freely combined and superimposed. Among them, the flowcharts and block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present disclosure. In this regard, each box in the flowchart or block diagram can represent a module, a program segment, or a part of a code, and the module, program segment, or a part of a code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in an order different from that marked in the accompanying drawings, for example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of boxes in the block diagram and / or flowchart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions. The numbering of each step in this article is only for the convenience of description and reference, and is not used to limit the order of execution. The specific execution order is determined by the technology itself, and those skilled in the art can determine various allowable and reasonable orders based on the technology itself.

[0121] Those skilled in the art will appreciate that, without conflict, the above-mentioned preferred solutions can be freely combined and superimposed.

[0122] It should be understood that the above-mentioned embodiments are merely illustrative and not restrictive. Without departing from the basic principles of the present invention, various obvious or equivalent modifications or substitutions that can be made by those skilled in the art to the above-mentioned details will all be included in the scope of the claims of the present invention.

Claims

1. An internally projected suspended HUD system, characterized in that: It comprises an image source (1), a reflective imaging component (2) and a one-way perspective film (4); wherein: The image source (1) is used to emit a light beam (3); The reflective imaging component (2) is used to directly receive the light beam (3) emitted by the image source (1) and reflect the light beam (3) to project a real image; The one-way perspective film (4) is arranged at the real image position so that the real image can achieve a suspension effect.

2. The internally projected suspended HUD system according to claim 1, characterized in that: An eye box (5) is arranged at a set distance from the one-way perspective film (4), and the real image is suitable for entering the human eye through the eye box (5).

3. The internally projected suspended HUD system according to claim 1, characterized in that: The one-way perspective film (4) is made of a polymer film or glass, and the film surface of the one-way perspective film (4) has a microstructure.

4. The internally projected suspended HUD system according to claim 1, characterized in that: The one-way perspective film (4) comprises a substrate and a multi-layer optical coating and an abrasion-resistant coating sequentially coated on the surface of the substrate.

5. The internally projected suspended HUD system according to claim 4, characterized in that: The multilayer optical coating comprises a first coating, a second coating and a third coating, wherein the first coating is a low refractive index layer coated on the surface of the substrate, the second coating is a high refractive index layer coated on the surface of the first coating, and the third coating is a low refractive index layer coated on the surface of the second coating.

6. The internally projected suspended HUD system according to claim 5, characterized in that: The substrate is glass or plastic, and the refractive index n is 1.5; the first coating, the second coating and the third coating are all silicon dioxide layers, wherein the refractive index n of the first coating is 1.46, and the thickness is 100nm; the refractive index n of the second coating is 2.4, and the thickness is 50nm; the refractive index n of the third coating is 1.46, and the thickness is 100nm.

7. The internally projected suspended HUD system according to any one of claims 1 to 6, characterized in that: The performance index P of the HUD system is obtained by the following formula: Wherein, T represents the light transmittance of the one-way perspective film (4), R represents the reflectivity of the one-way perspective film (4), and A max represents the maximum viewing angle of the one-way perspective film (4), C represents the real image color restoration degree of the one-way perspective film (4), U represents the light transmittance uniformity of the one-way perspective film (4), V represents the volume of the one-way perspective film (4), I represents the real image imaging effect, and W T , W R , W C , W U , W V , W I Used to indicate the weight of the above indicators.

8. The internally projected suspended HUD system according to any one of claims 1-6, characterized in that: The reflective imaging assembly (2) comprises a first reflector (21), a second reflector (22) and a third reflector (23) for reflecting a light beam (3); at least one of the first reflector (21), the second reflector (22) and the third reflector (23) is also used for converging the light beam (3); the first reflector (21) is located in the light emitting direction of the image source (1); the second reflector (22) is located in the light beam (3) reflecting direction of the first reflector (21); the third reflector (23) is located in the light beam (3) reflecting direction of the second reflector (22); and at the same time, the second reflector (22) is also located in the light beam (3) reflecting direction of the third reflector (23); the image source (1) emits a light beam (3) The light beam (3) is reflected by the first reflector (21) and the second reflector (22), the light beam (3) reflected by the second reflector (22) is emitted to the third reflector (23), and is reflected by the third reflector (23) and then emitted back to the second reflector (22), and finally the light beam (3) is emitted to the one-way perspective film (4) by the second reflector (22), and during the reflection process of the light beam (3), at least one of the first reflector (21), the second reflector (22) and the third reflector (23) converges the light beam (3), so that the light beam (3) emitted by the second reflector (22) forms the real image at the one-way perspective film (4).

9. The internally projected suspended HUD system according to claim 8, characterized in that: The surface formulas of the first reflector (21), the second reflector (22), and the third reflector (23) are: Among them, r 2 =x 2 +y 2 , z represents the sagittal height difference in the Z-axis direction, c represents the curvature, k represents the conic surface constant, and m and n represent the orders of x and y respectively.

10. The internal projection suspension HUD system according to any one of claims 1-6, characterized in that: The one-way perspective film (4) is located at the position of the vehicle's onboard instrument panel and / or the central control display screen.

Images