Projection lens and vehicle-mounted head-up display system

Abstract

The invention discloses a projection lens and a vehicle-mounted head-up display system. The projection lens comprises a projection objective lens front group, a diaphragm and a projection objective lens rear group which are sequentially arranged from an object plane to an image plane and are coaxially arranged, the projection objective lens front group comprises a first negative lens, a first positive lens and a second negative lens which are sequentially arranged from an object plane to a diaphragm and are coaxially arranged; wherein the first negative lens and the second negative lens are meniscus concave lenses, the concave surface of the first negative lens faces the first positive lens, and the concave surface of the second negative lens faces the diaphragm; and the projection objective lens rear group comprises a third negative lens, a second positive lens and a third positive lens which are sequentially arranged from the diaphragm to the image plane and are coaxially arranged. According to the technical scheme, the projection of an image to be projected is completed by using six lenses, compared with the prior art, the number of the lenses is small, the number of the contact surfaces of the lens glass surface and air is small, the light energy loss is greatly reduced, the light transmission efficiency is greatly improved, and meanwhile, the cost is correspondingly reduced due to the small number of the lenses.

Description

Technical Field

[0001] The present invention relates to the technical field of optical projection imaging, and in particular to a projection lens and a vehicle-mounted head-up display system. Background Art

[0002] The in-vehicle HUD (Head-Up Display) imaging system is a technology that projects vehicle information onto the windshield or independent transparent screen directly in front of the driver. The driver does not need to lower his head to check the displayed information on visual terminals such as mobile phone navigation, car instruments, and the car's central control screen, allowing him to concentrate on driving and reduce the probability of road traffic accidents.

[0003] In existing in-vehicle HUD imaging systems, the PGU system (Picture Generation Unit) is very complex, and the existing PGU projection lens has a large number of lenses, resulting in low light transmission efficiency. Summary of the Invention

[0004] In view of this, the present invention provides a projection lens to improve light transmission efficiency and reduce costs.

[0005] The present invention also provides a vehicle-mounted head-up display system comprising the projection lens.

[0006] As can be seen from the above technical solution, the projection lens provided by the present invention can complete the projection of the image to be projected using six lenses through this technical solution. Compared with the existing technology, due to the smaller number of lenses, the number of surfaces of the lens glass in contact with the air is reduced, the light energy loss is greatly reduced, and the light transmission efficiency is greatly increased. At the same time, due to the smaller number of lenses, the cost is also correspondingly reduced.

[0007] The present invention also provides a vehicle-mounted head-up display system. Since the above-mentioned projection lens is adopted, the system also has corresponding beneficial effects. For details, please refer to the above description and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0009] Figure 1 This is a system diagram of Example 1 of the vehicle-mounted projection lens of the present invention (excluding the object plane);

[0010] Figure 2 for Figure 1 Schematic diagram after adding light;

[0011] Figure 3 This is a system diagram of Example 1 of the vehicle-mounted projection lens of the present invention (including the object plane);

[0012] Figure 4 for Figure 3 Schematic diagram after adding light;

[0013] Figure 5 This is a spot diagram of Example 1 of the vehicle-mounted projection lens of the present invention;

[0014] Figure 6 1 is a root mean square diagram of the wavefront aberration of Example 1 of the vehicle-mounted projection lens of the present invention;

[0015] Figure 7 This is a distortion diagram of Example 1 of the vehicle-mounted projection lens of the present invention;

[0016] Figure 8 This is an MTF curve diagram of Example 1 of the vehicle-mounted projection lens of the present invention;

[0017] Figure 9 This is a system diagram of Example 2 of the vehicle-mounted projection lens of the present invention (excluding the object plane);

[0018] Figure 10 for Figure 9 Schematic diagram after adding light;

[0019] Figure 11 This is a system diagram of Example 2 of the vehicle-mounted projection lens of the present invention (including the object plane);

[0020] Figure 12 for Figure 11 Schematic diagram after adding light;

[0021] Figure 13 This is a spot diagram of Example 2 of the vehicle-mounted projection lens of the present invention;

[0022] Figure 14 This is a root mean square diagram of the wavefront aberration of Example 2 of the vehicle-mounted projection lens of the present invention;

[0023] Figure 15 This is a distortion diagram of Example 2 of the vehicle-mounted projection lens of the present invention;

[0024] Figure 16 This is an MTF curve diagram of Example 2 of the vehicle-mounted projection lens of the present invention;

[0025] Figure 17 A schematic diagram of the coordination between the lighting part and the projection lens of a head-up display system provided in an embodiment of the present application;

[0026] Figure 18 A schematic structural diagram of a first embodiment of a head-up display system provided in an embodiment of the present application;

[0027] Figure 19 A schematic structural diagram of a second embodiment of a head-up display system provided in an embodiment of the present application;

[0028] Figure 20 A schematic structural diagram of a third embodiment of a head-up display system provided in an embodiment of the present application;

[0029] Figure 21 A schematic structural diagram of a fourth embodiment of a head-up display system provided in an embodiment of the present application;

[0030] Figure 22 A schematic structural diagram of a fifth embodiment of a head-up display system provided in an embodiment of the present application;

[0031] Figure 23 A schematic diagram of the X-direction component of an image light ray in a fifth embodiment of a head-up display system provided by an embodiment of the present application;

[0032] Figure 24 A schematic diagram of the Y-direction component of image light in a fifth embodiment of a head-up display system provided in an embodiment of the present application;

[0033] Figure 25 This is a partial stereoscopic diagram of a fifth embodiment of a head-up display system provided in an embodiment of the present application.

[0034] The meanings of the reference numerals in the figures are as follows:

[0035] 1 is the first negative lens, 2 is the first positive lens, 3 is the second negative lens, 4 is the third negative lens, 5 is the second positive lens, 6 is the third positive lens, 7 is a prism, 8 is an aperture, 9 is the object plane, 13 is the image plane, and 14 is the DMD glass cover; 10 is an image generating unit, 20 is a diffusion element, 11 is a near-view diffusion sub-element, 12 is a far-view diffusion sub-element, 30 is a reflector assembly, 31 is a first reflector, 32 is a second reflector, 33 is a third reflector, and 40 is a holographic optical element;

[0036] 50 is a reflection component, 51 is a reflector 1, 52 is a reflector 2, 53 is a light deflection element; 60 is an intermediate image plane. DETAILED DESCRIPTION

[0037] The following is an explanation of some of the terms involved in this plan:

[0038] The spot diagram is one of the most commonly used evaluation methods in modern optical design. The smaller the spot diagram is, the smaller the diffuse spot of the optical system is and the smaller the aberration of the system is.

[0039] The root mean square (RMS) wavefront error is a method for quantifying the imaging quality of an optical system. It is the square root of the average of the squares of all wavefront errors in the optical system. Wavefront errors can be caused by a variety of factors, including deviations in the lens surface, non-ideal shapes of optical components, and scattering from optical materials. The RMS wavefront error can be used to evaluate the resolution and imaging quality of an optical system.

[0040] Field curvature: This refers to the curvature of the image field. When a flat object passes through a lens system, the image plane after all flat object points are focused does not coincide with the ideal image plane, but is instead a curved surface. The vertical axis of field curvature / distortion is the field of view angle. Generally, a good lens is one that can control field curvature to within 100 microns.

[0041] For automotive projection lenses, the most important imaging quality indicator is MTF. The design value of the imaging quality of the projection lens is not satisfactory. When measuring the optical transfer function (MTF), which characterizes the imaging quality, the MTF value of the projection lens at 50 line pairs per millimeter is usually less than 0.3. In the subsequent processing and assembly, errors in the material refractive index, the optical surface curvature radius, and the matching errors between the optical lens and the mechanical barrel will also be introduced. These errors usually reduce the MTF by 20%, which means that the MTF can usually only reach 0.24. In principle, such imaging quality is not enough to meet the clarity requirements during use.

[0042] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0043] The projection lens provided by the embodiment of the present invention is applied to a vehicle head-up display system, such as Figure 1 As shown, it includes: a projection objective lens front group, an aperture 8 and a projection objective lens rear group, which are arranged in sequence and coaxially from the object plane 9 to the image plane 13;

[0044] like Figure 1 and Figure 7 As shown, the front group of the projection objective comprises: a first negative lens 1, a first positive lens 2, and a second negative lens 3, which are sequentially arranged and coaxially disposed from the object plane 9 to the aperture 8; wherein the first negative lens 1 and the second negative lens 3 are meniscus concave lenses, and the concave surface of the first negative lens 1 faces the first positive lens 2, and the concave surface of the second negative lens 3 faces the aperture 8. It can also be understood that the convex surface of the first negative lens 1 faces the object plane 9, and the convex surface of the second negative lens 3 faces the first positive lens 2;

[0045] The rear group of the projection objective lens includes: a third negative lens 4, a second positive lens 5 and a third positive lens 6, which are arranged in sequence from the aperture 8 to the image plane 13 and are coaxially arranged. Figure 1 and Figure 9 As shown, the third negative lens 4 and the second positive lens 5 are cemented together to form a cemented lens, which enables the projection lens to be quickly assembled and reduces reflection and energy loss during the refraction process. Figure 1 and Figure 9 As shown, a prism 7 is provided between the third positive lens 6 and the image plane 13 to distribute light. In addition, the prism 7 is a standard part for ease of manufacture.

[0046] In the above technical solution, the image to be projected is formed on the image plane 13, and is sequentially projected onto the object plane 9 through the third positive lens 6, the second positive lens 5, the third negative lens 4, the aperture 8, the second negative lens 3, the first positive lens 2 and the first negative lens 1. The image propagation path can be referred to Figure 4 and Figure 12 As shown. Through this technical solution, the image to be projected is completed using six lenses. Compared with the existing technology, due to the smaller number of lenses, the number of surfaces of the lens glass in contact with the air is reduced, the light energy loss is greatly reduced, and the light transmission efficiency is greatly increased. At the same time, due to the smaller number of lenses, the cost is also reduced accordingly.

[0047] In an optional technical solution, Figure 1 and Figure 9 A DMD glass cover 14 is installed on the DMD chip between the prism 7 and the image plane 13. This glass cover 14 protects the DMD chip from dust and other particles that could cause pixel failure. It also isolates moisture, oxygen, and other particles, extending the life of the DMD chip. Furthermore, when the micromirrors are flipped, the inner surface of the DMD glass cover 14 maintains a safe distance from the top of the micromirrors to prevent contact.

[0048] To optimize the above technical solution, the DMD glass cover 14 is made of EAGLEXG material (i.e., high-performance alkali-free boroaluminosilicate glass), so that the DMD glass cover 14 has high light transmittance, ensuring that the display image is clear and bright.

[0049] In an optional technical solution, the first negative lens 1, the second negative lens 3 and the third negative lens 4 are made of H-ZF52 material, which is an optical glass with high refractive index and low dispersion and can meet projection requirements; wherein the H-ZF52 material is a heavy flint glass; and / or,

[0050] The first positive lens 2 and the third positive lens 6 are made of H-LAK3 material; H-LAK3 material has a high Abbe number, low dispersion and stability, and has good mechanical properties (resistance to scratches and wear, ensuring lens surface accuracy) and can meet projection requirements; wherein H-LAK3 material is a lanthanum crown glass; and / or,

[0051] The second positive lens 5 is made of H-ZK7 material, which has high refractive index and low dispersion and can meet projection requirements. The H-ZK7 material is a heavy crown glass.

[0052] In an optional technical solution, the first negative lens 1 and the third negative lens 4 are made of H-ZF52 material, which is an optical glass with high refractive index and low dispersion, and can meet projection requirements; and / or,

[0053] The first positive lens 2 and the third positive lens 6 are made of H-LAK3 material, which has high Abbe number, low dispersion and stability, and good mechanical properties (resistance to scratches and wear, ensuring lens surface accuracy) and can meet projection requirements; and / or,

[0054] The second negative lens 3 is made of H-ZF1 material, which has high refractive index, high dispersion characteristics and chemical stability, wherein H-ZF1 material is a heavy flint glass; and / or,

[0055] The second positive lens 5 is made of H-K9L material, which has high optical performance, chemical stability and process adaptability. H-K9L material is a colorless optical glass.

[0056] A vehicle head-up display system, Figures 18-20 As shown, it includes: an object plane 9 and the above-mentioned projection lens; a diffusion element 20 is provided at the position of the object plane 9, and the normal direction of the diffusion element 20 is set at an angle to the optical axis of the projection lens, as shown in FIG. Figure 3 As shown; the diffusing element 20 is preferably a diffuser film. In this technical solution, the diffuser film is positioned so that stray sunlight incident on the diffuser film from the outer edge of the windshield along the imaging optical path is at a certain angle to the optical axis of the projection lens. This prevents stray light from reaching the DMD image source surface, preventing it from overlapping with the desired image, effectively avoiding the impact of stray light. Furthermore, the angle between the diffuser film and the optical axis of the projection lens effectively reduces reflections from the projection lens' light hitting the diffuser film and reduces the size of the HUD.

[0057] A vehicle head-up display system includes the above-mentioned projection lens, such as Figure 1The main ray of the projection lens is arranged at an angle α to the optical axis, and the angle α is in the range of 1.7-2.7 degrees. Preferably, the angle α is 1.7 degrees. The prism 7 is a triangular glass body, and the optical axis is an imaginary straight line representing the central axis of the rotational symmetry of the optical system, as shown in FIG. Figure 17 shown.

[0058] In an optional technical solution, the image generation unit 10 may be composed of two parts: an illumination part and a projection lens. The illumination part includes lamp beads, collimation, and compound eyes.

[0059] The technical features mentioned above, the technical features described below, and the technical features shown individually in the accompanying drawings may be combined arbitrarily, as long as the combined technical features do not conflict with each other. All possible feature combinations are technical contents explicitly described in this document. Any of the multiple sub-features included in the same statement can be applied independently and does not necessarily have to be applied in conjunction with the other sub-features.

[0060] The present invention will be further described below with reference to specific embodiments:

[0061] In Example 1, Figure 1 and Figure 3 As shown, the first negative lens 1, the second negative lens 3 and the third negative lens 4 are made of glass material H-ZF52 lenses, the first positive lens 2 and the third positive lens 6 are made of glass material H-LAK3 lenses, the second positive lens 5 is made of glass material H-ZK7 lens, the aperture 8 is located between the second negative lens 3 and the third negative lens 4, and the prism 7 is made of glass material EAGLEXG. The glass material between the first negative lens 1 and the surface of the first positive lens 2 is H-ZF52, that is, the material of the entire first negative lens 1 (composed of surface 1 and surface 2); there is air between surface 2 and surface 3, and surface 3 and surface 4 constitute lens 2, and the corresponding glass material is H-LAK3. The relationship between subsequent lenses and surface numbers is similar, and the specific parameters of each component of this embodiment are shown in the following table;

[0062]

[0063] like Figure 5 As shown, in this embodiment, the geometric radius (maximum radius) of the entire optical system is less than 50 microns, meeting the system's requirements for aberration.

[0064] like Figure 6 As shown, in this embodiment, the root mean square of the wavefront difference is less than 0.5, indicating that the resolution and imaging quality of this embodiment meet the imaging requirements.

[0065] like Figure 7As shown, in this embodiment, the field curvature / distortion meets the imaging requirements of the optical system.

[0066] like Figure 8 As shown, in this embodiment, at a sampling frequency of 50 line pairs / mm, the MTF value of the entire field of view exceeds 0.4, indicating that the imaging quality of this embodiment is sufficient to meet the imaging quality requirements.

[0067] In Example 2, Figure 9 and Figure 12 As shown, the first negative lens 1 and the third negative lens 4 are made of glass material H-ZF52 lenses, the first positive lens 2 and the third positive lens 6 are made of glass material H-LAK3 lenses, the second negative lens 3 is made of glass material H-ZF1 lens, the second positive lens 5 is made of glass material H-K9L lens, and the aperture 8 is located between the second negative lens 3 and the third negative lens 4. The prism 7 is made of glass material EAGLEXG. The specific parameters of the various components of this embodiment are shown in the following table;

[0068]

[0069] like Figure 13 As shown, in this embodiment, the geometric radius (maximum radius) of the entire optical system is less than 50 microns, meeting the system's requirements for aberration.

[0070] like Figure 14 As shown, in this embodiment, the root mean square of the wavefront difference is less than 0.5, indicating that the resolution and imaging quality of this embodiment meet the imaging requirements.

[0071] like Figure 15 As shown, in this embodiment, the field curvature / distortion meets the imaging requirements of the optical system.

[0072] like Figure 16 As shown, in this embodiment, at a sampling frequency of 50 line pairs / mm, the MTF value of the entire field of view exceeds 0.4, which shows that the imaging quality of this embodiment is sufficient to meet the imaging quality requirements.

[0073] Technical effects of this projection lens:

[0074] 1. PGU projection lens (i.e. projection lens) has fewer lenses, high light transmission efficiency and lower cost. Due to the small number of lenses, the number of surfaces of the lens glass in contact with the air is reduced, which greatly reduces light energy loss and greatly increases light transmission efficiency. At the same time, due to the small number of lenses, the cost is also reduced accordingly.

[0075] Second, PGU projection lenses utilize a limited number of glass types. This reduces sources of error during their design and manufacturing, making image quality easily controllable. The patented invention, however, utilizes only three or four types of glass. These glasses are very common, produced year-round by glass factories, and the processing techniques used are highly sophisticated. Therefore, their physical and chemical properties are significantly superior to those of rarer and more infrequent glasses. In particular, the refractive index error is extremely small, closely matching the refractive index used in the software. This minimizes sources of error and makes image quality easily controllable.

[0076] Third, the patented PGU projection lens utilizes a technical solution that creates a certain angle between the diffuser film and the projection lens optical axis. This prevents stray light from overlapping the desired image and affecting the viewing experience. This prevents stray light from reaching the DMD image source surface, preventing it from overlapping the desired image and effectively preventing the effects of stray light.

[0077] Fourth, all PGU projection lenses utilize a spherical surface, offering excellent processability, low processing difficulty, and reduced costs. Image quality does not deteriorate with temperature fluctuations. This patented invention utilizes entirely glass, employing spherical lenses. This simplifies processing, utilizes mature testing technology, and is easy to assemble and adjust. Furthermore, glass is insensitive to temperature, and its spherical surface shape remains unchanged with temperature changes, ensuring that temperature fluctuations have no impact on image quality.

[0078] Fifth, the patented PGU projection lens offers high-quality imaging, ensuring optimal use. This patented lens was repeatedly optimized during design. With a small number of lenses and a limited variety of lens glass, the designed MTF value at 50 line pairs per millimeter reaches over 0.4. Even accounting for subsequent errors, the final MTF value reaches 0.32, which is sufficient to meet operational requirements.

[0079] Sixth, the invention patent takes into account the angle between the outgoing principal ray and the optical axis. The angle between the outgoing principal ray and the optical axis of the designed PGU projection lens is less than 2.7°, far less than 15°. Because the DMD image source is a Lambertian radiator, the radiation energy increases the closer to the optical axis. Therefore, the invention patent maximizes the utilization of the DMD's radiation energy.

[0080] In one embodiment, see Figure 18 and Figure 19The embodiment of the present application discloses a human-computer interaction system (i.e., a head-up display system) integrating an ARHUD and a holographic instrument, comprising: an image generation unit 10, a diffusion element 20, a reflector assembly 30, and a holographic optical element 40; wherein the image generation unit 10 includes but is not limited to the above-mentioned projection lens. The projection lens has the following advantages: first, the number of lenses is small, the light transmission efficiency is high, and the cost is reduced; second, the PGU projection lens uses a small number of glass types, which reduces the error sources during the design and manufacture of the PGU projection lens and makes the imaging quality easy to control; third, the projection lenses all use spherical surfaces, which have good processability; and fourth, the projection lens has high imaging quality and can meet the requirements of use.

[0081] The image generation unit 10 is used to generate a target light beam, which includes a first light beam and a second light beam, wherein the first light beam carries near-view image information, and the second light beam carries far-view image information, and the content of the image information carried by the first light beam and the second light beam is different; the image generation unit 10 can generate two light beams carrying different projection information through its internal optical elements and imaging technology, for example, one light beam carries Class A projection information and the other light beam carries Class B projection information.

[0082] See also Figure 18 The diffusing element 20, through its internal microstructure, reflects and refracts the incident light multiple times, thereby achieving uniform light diffusion. In this solution, the diffusing element 20 is disposed along the transmission path of the second light beam to diffuse the second light beam. To ensure that the second light beam is clearly and accurately presented in the driver's field of view, the projected second light beam needs to be diffused and homogenized. After diffusion, the second light beam is projected at the second position as a virtual image, which can display the projection data more clearly and three-dimensionally.

[0083] See also Figure 18 The reflector assembly 30 is an optical component primarily composed of a reflector and a package. In this embodiment, the reflector assembly 30 is used to project the target light beam to a corresponding target position, wherein the target light beams are the first light beam and the second light beam that cannot be directly projected at the corresponding target position. The target positions include a first position on the windshield where the holographic optical element 40 is located and a second position on the windshield, and the coordinates of the first position and the second position on the windshield are different. In this embodiment, the reflector assembly 30 is used to at least reflect the second light beam to the second position. The second light beam projected at the second position will form a distant image on the windshield. The first light beam can be projected at the first position after being reflected by the reflector assembly 30, or can be directly projected at the first position without being reflected by the reflector assembly 30.

[0084] See also Figure 18 Holographic optical elements (HOEs) 40 are optical components fabricated based on the principles of holography and are typically fabricated on a photosensitive film. They function based on the diffraction principle of light and are a type of diffractive optical element. In this embodiment, the HOEs 40 diffract the first light beam to form a near-field image on the windshield.

[0085] See also Figure 18 During the imaging process, the human-computer interaction system for the fusion of an ARHUD and a holographic instrument disclosed in an embodiment of the present application generates a first light beam and a second light beam carrying different projection information via an image generation unit 10. A diffusion element 20 is then used to diffuse and homogenize the second light beam. A reflector assembly 30 then projects the first and second light beams to first and second positions, respectively. The first light beam projected at the first position undergoes a diffraction effect caused by a holographic optical element 40, forming a HOE real image (a HOE real image is a real image generated by a holographic optical element (HOE)) on the windshield. This HOE real image displays the projection information carried by the first light beam. The second light beam projected at the second position forms a distant virtual image on the windshield, which displays the projection information carried by the second light beam. This human-computer interaction system for the fusion of an ARHUD and a holographic instrument utilizes only a single holographic optical element and an optical transmission system to display both projection information. This system offers a simple structure and a compact size.

[0086] See also Figure 18In the technical solution disclosed in this embodiment, the type of image generation unit 10 can be selected based on design requirements. For example, the image generation unit 10 can be any one of DLP, LCOS, LBS, or Micro LED-based image generation units. Digital Light Processing (DLP) technology is a projection technology based on a digital micromirror device (DMD). A DMD chip is an optical microelectromechanical system that can achieve spatial light modulation. It contains millions of tiny aluminum lenses, each corresponding to a pixel. The number of lenses determines the display resolution. Liquid Crystal on Silicon (LCOS) technology is a new display technology that combines the advantages of LCD (Liquid Crystal Display) and DLP (Digital Light Processing). The image generation unit (PGU) based on laser beam scanning (LBS) technology is a core component of the HUD (Head-Up Display) system. Of course, the above-mentioned various types of image generation units are only examples in this application. During design, users can also choose other types of image generation units according to their own design requirements.

[0087] See also Figure 18 In this embodiment, to ensure that the first and second light beams generated by the image generation unit 10 do not interfere with or confuse each other, the image generation unit 10 may include a first display area and a second display area. The first display area is used to generate the first light beam, and the second display area is used to generate the second light beam. The light beams generated by the image generation unit 10 may have different emission angles, so that the light beams separate from each other after emission, thereby facilitating the arrangement of the diffusion element 20 and the reflector assembly 30.

[0088] See also Figure 18 In the technical solution disclosed in this embodiment, the specific type of the diffusion element 20 can be selected according to the design requirements. It can be any diffusion membrane known in the existing solution that can meet the diffusion requirements of this solution, for example, it can be a gradient diffusion membrane or a deflection diffusion membrane.

[0089] See also Figure 18In the technical solution disclosed in this embodiment, the specific structure of the reflector assembly 30 can be arranged according to the incident direction of the light beam to be intervened and its corresponding target position. In this embodiment, the reflector assembly 30 may include at least one reflector group, each reflector group corresponds to a different light beam, and the reflector group is used to reflect the incident light beam corresponding to the reflector group to the target position corresponding to the light beam.

[0090] For example, see Figure 18 The reflector assembly 30 includes a first reflector group, and the reflector assembly 30 includes a first reflector 31 and a second reflector 32. The first reflector 31 and the second reflector 32 are arranged opposite to each other so as to reflect the incident second light beam to its corresponding second position through the first reflector 31 and the second reflector 32. When the optical path of the second light beam is corrected using the first reflector 31 and the second reflector 32, the positions and angles of the first reflector and the second reflector can be arranged according to the incident angle of the second light beam and its corresponding second position.

[0091] In this embodiment, see Figure 18 The type of the reflector in the reflector assembly 30 can be set according to the reflection requirements. The reflector can be a plane mirror or a curved mirror, for example Figure 18 In the illustrated embodiment, the first reflector may be a plane mirror or a curved mirror, and the second reflector is a curved mirror.

[0092] In this embodiment, see Figure 18 , the reflector group may further include a second reflector group, the second reflector group being used to reflect the first light beam to its corresponding first position. In the technical solution disclosed in this embodiment, when it is necessary to use the reflector assembly 30 to correct the path of the first light beam so that the first light beam falls on the first position, it is necessary to set a second reflector group in the reflector assembly 30 for correcting the path of the first light beam. The number of reflectors in the reflector group and the distribution of the reflectors can be determined based on the incident angle of the first light beam and the first position. For example, Figure 19 In the example, only one reflector is needed to reflect the first light beam to the first position. Therefore, the second reflector group can include only one reflector, which is recorded as the third reflector 33. The third reflector 33 is used to reflect the incident light beam to the first position. The third reflector can be a plane mirror. The reflection angle of the third reflector can be based on the incident angle of the first light beam and the specific position of the first position.

[0093] In the technical solution disclosed in this embodiment, see Figure 18The projection information carried by the first and second light beams can be determined according to the requirements involved. The user can autonomously adjust the specific content of the projection information carried by the first and second light beams generated by the image generation unit 10 through system control according to their own needs. For example, in this embodiment, the projection information carried by the first light beam includes vehicle status information, and the information carried by the second light beam includes non-vehicle status information. The vehicle status information includes at least instrument information, any one or more combinations of vehicle speed information, fuel level information, prompt information, and alarm information; the non-vehicle status information includes at least any one or more combinations of navigation positioning information, traffic safety warning information, smart office information, and entertainment information.

[0094] In this embodiment, when a target user (in a car scenario, the target user can be the driver) views the projected images at the first and second positions, they may focus more on data in a specific area of ​​the projected images. Furthermore, users may adapt differently to projected images of varying brightness in different ambient brightness levels. For example, in high ambient brightness, the projected image brightness may need to be increased, while in low ambient brightness, the projected image brightness may need to be decreased. To enable eye-tracking and adaptive brightness adjustment of the projected images at the first and second positions, the ARHUD and holographic instrument integrated human-computer interaction system disclosed in this embodiment may further include an optoelectronic control module. This optoelectronic control module is configured to enable eye-tracking and adaptive brightness adjustment of the projected images at the first and second positions. In this case, the ARHUD and holographic instrument integrated human-computer interaction system can automatically adjust the projected images at the first and second positions based on the user's line of sight and automatically adjust the brightness of the projected images at the first and second positions, ensuring that the projected images follow the user's line of sight and automatically adjust their brightness based on ambient brightness.

[0095] In another specific embodiment, in order to solve the problems of complex structure and large system volume of the dual-optical path HUD imaging system, the present application provides a dual head-up display fusion imaging system (i.e., a head-up display system). The dual head-up display fusion imaging system generates two light beams carrying different projection information through an image generation unit, one of which is directly reflected by the windshield and displayed, and the other light beam is displayed after passing through a holographic optical element. Therefore, the optical path system only requires one holographic optical element and optical transmission system, with a simple structure and small volume.

[0096] See also Figure 20The embodiment of the present application discloses a dual head-up display fusion imaging system, comprising: an image generation unit 10, a diffusion element 20, a reflector assembly 30, and a holographic optical element 40; wherein the image generation unit 10 includes but is not limited to the above-mentioned projection lens. The projection lens has the following advantages: first, the number of lenses is small, the light transmission efficiency is high, and the cost is reduced; second, the PGU projection lens uses a small number of glass types, and when the PGU projection lens is designed and manufactured, there are fewer sources of error and the imaging quality is easy to control; third, the projection lenses all use spherical surfaces, which have good workability; fourth, the projection lens has high imaging quality and can meet the requirements of use.

[0097] See also Figure 20 The image generation unit 10 is configured to generate a target light beam, the target light beam comprising a first light beam and a second light beam, the first light beam carrying near-view image information, the second light beam carrying far-view image information, the near-view image information and the far-view image information containing different data contents. The image generation unit 10 can generate two light beams carrying different projection image information using its internal optical elements and imaging technology, for example, one light beam carrying type A image information and the other light beam carrying type B image information;

[0098] See also Figure 20 The diffusion element 20 includes a near-field diffusion sub-element 11 and a far-field diffusion sub-element 12. The near-field diffusion sub-element 11 is used to diffuse and homogenize the first light beam, and the far-field diffusion sub-element 12 is used to diffuse and homogenize the second light beam. In this solution, the diffusion element 20 can diffuse and homogenize the light beam emitted by the image generation unit 10 to improve the visibility and readability of the projected image.

[0099] See also Figure 20 The reflector assembly is an optical component primarily composed of a reflector and a package. In this embodiment, the reflector assembly 30 is used to project the diffused target light beam to a corresponding target position, wherein the target position includes a first position on the windshield where the holographic optical element 40 is located and a second position on the windshield, wherein the coordinates of the first position and the second position on the windshield are different. In this embodiment, the reflector assembly 30 is used to reflect the desired light beam. The first light beam projected at the first position, either directly or after correction by the reflector assembly, undergoes a diffraction effect under the action of the holographic optical element 40, thereby forming a near-field image. The second light beam projected at the second position, after correction by the reflector assembly, forms a far-field image on the windshield, thereby completing the projection of two images.

[0100] See also Figure 20Holographic optical elements (HOEs) are optical components fabricated based on the principles of holography and are typically fabricated on photosensitive film materials. They function by forming projected images based on the principle of light diffraction. In this embodiment, the holographic optical element 40 is used to diffract the first light beam to form a near-field image.

[0101] See also Figure 20 During the imaging process, the dual head-up display fusion imaging system disclosed in the embodiments of the present application generates a first light beam and a second light beam carrying different projection information through an image generation unit 10. A diffusion element 20 is then used to uniformly diffuse the first and second light beams. A reflector assembly 30 is then used to correct the beam paths, ultimately projecting the first light beam to a first position and the second light beam to a second position. The first light beam projected at the first position undergoes a diffraction effect under the action of the holographic optical element 40, forming a near-field image in front of the windshield. This near-field image displays the projection information carried by the first light beam. The second light beam projected at the second position forms a far-field image in front of the windshield. This far-field image displays the projection information carried by the second light beam. This dual head-up display fusion imaging system utilizes only a single holographic optical element and an optical transmission system to display both projection information. This system is simple in structure and compact in size.

[0102] See also Figure 20In the technical solution disclosed in this embodiment, the type of image generation unit 10 can be selected based on design requirements. For example, the image generation unit 10 can be any one of DLP, LCOS, LBS, or Micro LED-based image generation units. Digital Light Processing (DLP) technology is a projection technology based on a digital micromirror device (DMD). A DMD chip is an optical microelectromechanical system that can achieve spatial light modulation. It contains millions of tiny aluminum lenses, each corresponding to a pixel. The number of lenses determines the display resolution. Liquid Crystal on Silicon (LCOS) technology is a new display technology that combines the advantages of LCD (Liquid Crystal Display) and DLP (Digital Light Processing). The image generation unit (PGU) based on laser beam scanning (LBS) technology is a core component of the HUD (Head-Up Display) system. Of course, the above-mentioned various types of image generation units are only examples in this application. During design, users can also choose other types of image generation units according to their own design requirements.

[0103] In this embodiment, see Figure 20 To ensure that the first and second light beams generated by the image generation unit 10 do not interfere with or confuse each other, the image generation unit 10 may include a first display area for generating the first light beam and a second display area for generating the second light beam. The light beams generated by the image generation unit 10 may have different emission angles, allowing them to separate from each other after emission, thereby facilitating the arrangement of the diffusion element 20 and the reflector assembly 30.

[0104] In this embodiment, see Figure 20 The first sub-diffusing element and the second sub-diffusing element are independent packaging structures or combined integral packaging structures. When the first sub-diffusing element and the second sub-diffusing element are combined integrally packaged, the angles between the first sub-diffusing element and the first light beam, and the angles between the second sub-diffusing element and the second light beam match each other, so that the target light beam is clearly imaged.

[0105] In the technical solution disclosed in this embodiment, see Figure 20The diffusion element 20 mainly diffuses the light beam through the diffusion film inside it. The specific type of the diffusion film in the diffusion element 20 can be selected according to the design requirements. It can be any diffusion film known in the existing scheme that can meet the diffusion requirements of this scheme, for example, it can be a gradient diffusion film or a deflection diffusion film.

[0106] In the technical solution disclosed in this embodiment, see Figure 20 The specific structure of the reflector assembly 30 can be arranged according to the number of light beams required to be intervened, the incident directions of these light beams, and the target positions corresponding to each light beam. In this embodiment, the reflector assembly 30 may include at least one reflector group, each reflector group corresponds to a different light beam, and the reflector group is used to reflect the incident light beam corresponding to the reflector group to the target position corresponding to the light beam.

[0107] For example, see Figure 20 The reflector assembly 30 includes a first reflector group, and the reflector assembly 30 includes a first reflector 31 and a second reflector 32. The first reflector 31 and the second reflector 32 are arranged opposite to each other, so as to reflect the second light beam to its corresponding second position through the first reflector 31 and the second reflector 32. When correcting the optical path of the second light beam, the positions and angles of the first reflector 31 and the second reflector 32 can be arranged according to the incident angle of the second light beam and its corresponding target position.

[0108] In this embodiment, see Figure 20 The type of the reflector in the reflector assembly 30 can be set according to the reflection requirements. The reflector can be a plane mirror or a curved mirror, for example Figure 20 In the illustrated embodiment, the first reflector may be a plane mirror or a curved mirror, and the second reflector may be a curved mirror.

[0109] In this embodiment, see Figure 20 , after passing through the near-field diffusion sub-element, the first light beam can be directly projected to the first position, or it can be projected to the first position after being reflected by the reflector in the reflector assembly. In this case, the reflector group can also include a second reflector group, and the second reflector group is used to reflect the first light beam to its corresponding first position. Similarly, the number and distribution of the reflectors in the second reflector group can be determined based on the incident angle of the first light beam and the first position. For example, Figure 21 In the example, only one third reflector 33 is needed to reflect the first light beam to the first position. The third reflector can be a plane mirror, and the reflection angle of the third reflector can be determined based on the incident angle of the first light beam and the specific position of the first position.

[0110] In the technical solution disclosed in this embodiment, see Figure 20 The projection information carried by the first and second light beams can be determined according to the requirements involved. The user can autonomously adjust the specific content of the projection information carried by the first and second light beams generated by the image generation unit 10 through system control according to their own needs. For example, in this embodiment, the projection information carried by the first light beam includes vehicle status information, and the information carried by the second light beam includes non-vehicle status information. The vehicle status information includes at least instrument information, any one or more combinations of vehicle speed information, fuel level information, prompt information, and alarm information; the non-vehicle status information includes at least any one or more combinations of navigation positioning information, traffic safety warning information, smart office information, and entertainment information.

[0111] Furthermore, the present application also discloses a car, which can be equipped with the dual head-up display fusion imaging system introduced in any one of the above embodiments.

[0112] Based on the above scheme, see Figure 20 and Figure 21 The dual head-up display fusion imaging system disclosed in this application, on the one hand, combines the advantages of HOE and HUD, accurately controls and guides the projection light of the HOE optical path system, and achieves efficient and high-resolution imaging in a relatively small space. The combination of the two can flexibly design the optical path according to the interior space and shape of the vehicle, and optimize the interior space layout; on the other hand, different imaging methods can not only ensure the stability of near-field information, but also enhance the far-field depth information experience, improve the overall display effect, and create a more excellent visual experience and information interaction platform for the driver.

[0113] In an optional technical solution, if Figure 22 and Figure 25 As shown, a vehicle-mounted head-up display system includes: a projection lens; and also includes: a reflection component 50;

[0114] The reflective assembly 50 is disposed on a side of the vehicle's windshield 70 located within the vehicle interior and is configured to reflect image light emitted from the projection lens toward the windshield. The image light emitted by the projection lens passes through the reflective assembly 50 and then forms a virtual image on the windshield 70. The driver, seated in the vehicle's eye box, can clearly see the information presented by the virtual image (e.g., vehicle speed, rotational speed, power consumption, gear position, and other auxiliary function information).

[0115] like Figure 22 and Figure 24 As shown, the reflective assembly 50 includes: a reflector 1 51 and a reflector 2 52 arranged in sequence;

[0116] The reflector 1 51 is used to reflect the image light emitted by the projection lens onto the reflector 2 52 , and the reflector 2 52 is used to reflect the image light reflected by the reflector 1 51 onto the windshield to form a virtual image;

[0117] The first reflector 51 is a concave mirror, so that the image light reflected by the first reflector 51 forms an intermediate image plane 60 on the path toward the second reflector 52. The intermediate image plane 60 is the intermediate image plane of the Y-direction component of the image light.

[0118] like Figure 22 As shown, the second reflector 52 is a concave mirror. The concave surface of the first reflector 51 and the concave surface of the second reflector 52 are arranged opposite to each other, which can reflect the image light while further compressing the volume of the vehicle-mounted head-up display system.

[0119] In the above-described technical solution, during use, image light emitted from the projection lens sequentially passes through reflector 1 51 and reflector 2 52. Because reflector 1 51 is a concave mirror, the image light reflected by reflector 1 51 forms an intermediate image plane 60 on its way to reflector 2 52. In layman's terms, intermediate image plane 60 means that the image light reflected by reflector 1 51 converges near the focal point of reflector 1 51, causing the emitted image light to exchange vertically with the image light on reflector 1 51 before being emitted to reflector 2 52. Specifically, the surface of reflector 1 51 has a large curvature in the Y direction, forming a concave Y-curved surface. This allows the Y-direction component of the light emitted from the projection lens to converge on its way to reflector 2 52 (i.e., to form intermediate image plane 60). This configuration allows reflector 2 52 to enclose more space below the light path than conventional non-converging automotive head-up display systems, allowing for a more compact arrangement of the diffuser mounting structure and other components, further reducing the size of the HUD.

[0120] Optimize the above technical solutions, such as Figure 22 and Figure 24 As shown, a light deflecting element 53 is provided between reflector 1 51 and the projection lens. This element converges the Y-direction component of the image light passing through it (which can be understood as converging along the length of a surface). This increases the degree of overlap of the image light emitted by the projection lens on reflector 1 51, reducing the Y-direction dimensions of reflector 1 51 and thereby reducing the volume of the HUD. It should be noted that the light deflecting element ensures that the exit angle of the image light passing through it matches the incident angle of the reflective component, primarily by deflecting the Y-direction component of the image light. Furthermore, the provision of light deflecting element 53 allows the intermediate image plane 60 to be formed closer to reflector 1 51, further reducing the distance between reflector 1 51 and reflector 2 52, thereby reducing the volume of the in-vehicle head-up display system.

[0121] In an optional technical solution, the light deflecting element 53 includes: a Fresnel lens, a free-form surface lens and a deflecting gradient diffusion film sequentially arranged between the projection lens and the reflector 1 51;

[0122] After the image light emitted by the projection lens passes through the Fresnel lens, free-form surface lens, and deflective gradient diffusion film in sequence, the Y-direction component of the image light is deflected and converged on reflector 1 51. Specifically, the Fresnel lens, free-form surface lens, and deflective gradient diffusion film can be arranged near the image plane of the projection lens to achieve pupil matching of the Y-direction component and improve light efficiency. It should be noted that both the Fresnel lens and the free-form surface lens are arranged in an area near the deflective gradient diffusion film and secured by structural members. In one embodiment, the Fresnel lens, free-form surface lens, and deflective gradient diffusion film form an integrated structure.

[0123] In an optional technical solution, the curvature of the concave free-form surface of the reflector 1 51 and the reflector 2 52 can be flexibly optimized and adjusted according to the automobile environment and customer parameter requirements.

[0124] In an optional technical solution, if Figure 23 As shown, when specifically used with the projection lens, the projection lens' exit pupil is close to the image light's X-direction entrance pupil, located near the PGU lens's middle aperture. At this point, the X-direction component of the projection lens's image light is divergent by the time it reaches reflector 2 52. It should be noted that the light deflecting element 53 cannot converge the X-direction component of the projection lens's image light.

[0125] It should be noted that Figure 23 The X-direction entrance pupil is based on the image light emitted by the projection lens. Figure 24 The entrance pupil in the Y direction is referenced by the image light passing through the light deflecting element 53 .

[0126] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0127] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A projection lens, applied to a vehicle head-up display system, characterized in that: include: A projection objective lens front group, an aperture (8) and a projection objective lens rear group arranged in sequence and coaxially from the object plane (9) to the image plane (13); The front group of the projection objective lens comprises: a first negative lens (1), a first positive lens (2) and a second negative lens (3) which are sequentially arranged and coaxially disposed from the object plane (9) to the aperture (8); wherein the first negative lens (1) and the second negative lens (3) are meniscus concave lenses, and the concave surface of the first negative lens (1) faces the first positive lens (2), and the concave surface of the second negative lens (3) faces the aperture (8); The rear group of the projection objective lens comprises: a third negative lens (4), a second positive lens (5) and a third positive lens (6) arranged in sequence and coaxially from the aperture (8) to the image plane (13); the third negative lens (4) and the second positive lens (5) are glued together to form a glued lens; and a prism (7) is provided between the third positive lens (6) and the image plane (13).

2. The projection lens according to claim 1, wherein: A DMD glass cover plate (14) is provided on the DMD chip between the prism (7) and the image plane (13).

3. The projection lens according to claim 2, wherein: The DMD glass cover (14) is made of EAGLEXG material.

4. The projection lens according to claim 1, wherein: The first negative lens (1), the second negative lens (3) and the third negative lens (4) are made of H-ZF52 material; and / or, The first positive lens (2) and the third positive lens (6) are made of H-LAK3 material; and / or, The second positive lens (5) is made of H-ZK7 material.

5. The projection lens according to claim 1, wherein: The first negative lens (1) and the third negative lens (4) are made of H-ZF52 material; and / or, The first positive lens (2) and the third positive lens (6) are made of H-LAK3 material; and / or, The second negative lens (3) is made of H-ZF1 material; and / or, The second positive lens (5) is made of H-K9L material.

6. The projection lens according to claim 1, wherein: The first negative lens (1), the first positive lens (2), the second negative lens (3), the third negative lens (4), the second positive lens (5) and the third positive lens (6) are all spherical lenses.

7. A vehicle head-up display system, characterized in that: include: An object plane (9) and a projection lens as claimed in any one of claims 1 to 6; a diffusion element (20) is provided at the position of the object plane (9), and a normal direction of the diffusion element (20) is arranged at an angle to the optical axis of the projection lens.

8. A vehicle head-up display system, characterized in that: The projection lens according to any one of claims 1 to 6 is provided, wherein the main ray emitted by the projection lens is arranged at an angle with the optical axis thereof, and the angle is in the range of 1.7-2.7 degrees.

9. A vehicle head-up display system, characterized in that: It comprises an image generating unit (10), a diffusion element (20) and a reflector assembly (30), wherein the image generating unit (10) comprises the projection lens according to any one of claims 1 to 6; The image generating unit (10) is used to generate a first light beam and a second light beam, the first light beam carrying near-view image information, and the second light beam carrying far-view image information; The diffusion element (20) is used to diffuse and homogenize the second light beam; The reflector assembly (30) is used to reflect the first light beam and / or the diffused second light beam to a target position corresponding to the windshield, wherein the target position includes a first position on the windshield where the holographic optical element (40) is located, and a second position on the windshield; The first light beam is diffracted at a first position of the windshield to form a real image, and the diffused second light beam is reflected at a second position of the windshield to form a distant virtual image in front of the windshield; The image generation unit (10) is an image generation unit based on DLP / LCOS / LBS / Micro LED; The image generating unit (10) comprises a first display area and a second display area, the first display area is used to generate a first light beam, and the second display area is used to generate a second light beam.

10. A vehicle head-up display system, characterized in that: It comprises an image generating unit (10), a diffusion element (20) and a reflector assembly (30), wherein the image generating unit (10) comprises the projection lens according to any one of claims 1 to 6; The image generation unit (10) is used to generate a target light beam, the target light beam comprising a first light beam and a second light beam, the first light beam carrying near-view image information, and the second light beam carrying far-view image information; The diffusion element (20) comprises a near-view diffusion sub-element (11) and a far-view diffusion sub-element (12), wherein the near-view diffusion sub-element (11) is used to diffuse and homogenize the first light beam, and the far-view diffusion sub-element (12) is used to diffuse and homogenize the second light beam; The reflector assembly (30) is used to reflect the diffused and homogenized target light beams to target positions corresponding to the windshield, wherein the target positions include a first position on the windshield where the holographic optical element (40) is located, and a second position on the windshield; The first light beam after diffusion and homogenization generates a diffraction effect at the first position to form a near-view virtual image in front of the windshield, and the second light beam after diffusion and homogenization is reflected at the second position to form a far-view virtual image in front of the windshield; The image generation unit (10) is an image generation unit based on DLP / LCOS / LBS / Micro LED; The image generating unit includes a first display area and a second display area, the first display area is used to generate a first light beam, and the second display area is used to generate a second light beam.

11. A vehicle head-up display system, characterized in that: The projection lens comprises the projection lens according to any one of claims 1 to 6; and further comprises: a reflection component (50); The reflection assembly (50) comprises: a first reflector (51) and a second reflector (52) arranged in sequence; The reflector 1 (51) is used to reflect the image light emitted by the projection lens onto the reflector 2 (52), and the reflector 2 (52) is used to reflect the image light reflected by the reflector 1 (51) onto the windshield to form a virtual image; Wherein, the reflector 1 (51) is a concave mirror, so that the image light reflected by the reflector 1 (51) forms an intermediate image plane (60) on the path toward the reflector 2 (52), and the intermediate image plane (60) is the intermediate image plane of the Y-direction component of the image light; The second reflector (52) is a concave mirror, and the concave surface of the first reflector (51) and the concave surface of the second reflector (52) are arranged opposite to each other.

12. The vehicle-mounted head-up display system according to claim 11, characterized in that: A light deflection element (53) is provided between the reflector 1 (51) and the projection lens, and the light deflection element (53) converges the Y-direction component of the image light passing through it.

13. The vehicle-mounted head-up display system according to claim 12, characterized in that: The light deflection element (53) comprises: a Fresnel lens, a free-form surface lens and a deflection gradient diffusion film which are sequentially arranged between the projection lens and the reflector 1 (51); After the image light emitted by the projection lens passes through the Fresnel lens, the free-form surface lens and the deflection gradient diffusion film in sequence, the Y-direction component of the image light is deflected and converged on the reflector 1 (51).

Images