Display lens group and head-up display device

Abstract

The invention relates to a display lens group and a head-up display device. The display lens group sequentially comprises a first lens, a reflector, a second lens, a third lens and an image display unit along the propagation direction of the light path, the first lens has positive diopter, the second lens has positive diopter, the third lens has negative diopter, and the image display unit is used for receiving light passing through the third lens and generating an image; the reflector is arranged between the first lens and the second lens and is used for reflecting the light emitted by the first lens to the second lens. According to the display lens group, through cooperation of the first lens, the second lens and the third lens, the display quality of the display lens group can be effectively improved, light path turning is achieved through the reflector, and the size of the display lens group can be effectively reduced.

Description

Technical Field

[0001] The present application relates to the technical field of head-up display, and in particular to a display lens assembly and a head-up display device. Background Art

[0002] The miniaturization of augmented reality head-up displays (AR HUDs) is crucial for their effective adaptation and widespread adoption in numerous real-world applications. In the automotive sector, in particular, miniaturized AR HUDs can be more flexibly installed above the dashboard of various vehicle types, whether compact sedans or larger vehicles, without taking up too much cockpit space.

[0003] However, the head-up display in the related art is usually difficult to achieve both miniaturization and better display effects. Summary of the Invention

[0004] Based on this, it is necessary to provide a display lens assembly and a head-up display device to address the problem that head-up displays in related technologies are generally difficult to achieve both miniaturized design and better display effects.

[0005] According to one aspect of the present application, a display lens assembly is provided. Along the propagation direction of the light path, the display lens assembly includes:

[0006] A first lens having positive refractive power;

[0007] a second lens having positive refractive power;

[0008] a third lens having negative refractive power;

[0009] an image display unit, configured to receive the light passing through the third lens and generate an image; and

[0010] The reflector is disposed between the first lens and the second lens and is used to reflect the light emitted by the first lens to the second lens.

[0011] In one embodiment, the reflector is provided on one side of the first lens along the first direction, the second lens is provided on one side of the reflector along the second direction, and along the second direction, the third lens and the image display unit are provided in sequence on the side of the second lens away from the reflector;

[0012] The first direction and the second direction intersect with each other.

[0013] In one embodiment, the display lens assembly satisfies:

[0014] 1.0<f1 / f<2.0;

[0015] 0.4<f2 / f<1.1;

[0016] 0.1<︱f3 / f︱<0.6;

[0017] Wherein, f is the focal length of the display lens assembly, f1 is the focal length of the first lens, f2 is the focal length of the second lens, and f3 is the focal length of the third lens.

[0018] In one embodiment, the display lens assembly further satisfies:

[0019] 0.3<f / TTL<0.9;

[0020] Wherein, f is the focal length of the display lens assembly, and TTL is the total optical length of the display lens assembly.

[0021] In one embodiment, the first lens, the second lens and the third lens are all aspherical lenses.

[0022] In one embodiment, the display lens assembly further satisfies:

[0023] 1.0<|R1 / R2|<5.0;

[0024] 0.5<|R2 / R3|<4.0;

[0025] Among them, R1 is the curvature radius of the light incident surface of the first lens at the paraxial position, R2 is the curvature radius of the light incident surface of the second lens at the paraxial position, and R3 is the curvature radius of the light incident surface of the third lens at the paraxial position.

[0026] In one embodiment, the reflector includes a reflective surface, the reflective surface is a plane, and an angle θ between the reflective surface and the axis of the second lens satisfies: 25°<θ<55°.

[0027] In one embodiment, at the near optical axis, the light entrance surface of the first lens is convex, and the light exit surface is convex; the light entrance surface of the second lens is concave, and the light exit surface is convex; the light entrance surface of the third lens is convex, and the light exit surface is concave.

[0028] In one embodiment, the display lens assembly further includes an aperture, and the aperture is disposed on a side of the first lens facing away from the reflector.

[0029] According to another aspect of the present application, a head-up display device is provided, comprising the display lens assembly in any one of the above embodiments.

[0030] The above-mentioned display lens group modulates the light through the first lens, second lens and third lens arranged in sequence along the propagation direction of the optical path, and then generates an image through the image display unit. Among them, the first lens has a positive refractive power, which is conducive to converging light to reduce the aberration of the system, so that the light can be effectively transmitted to the reflector and the second lens, which is conducive to the clarity and brightness of the image. The second lens has a positive refractive power, which further optimizes the transmission path of the light and adjusts the divergence of the light, thereby facilitating a smooth transition of the light, helping to control the high-order aberrations of the light, improving the uniformity and color reproduction of the imaging, and further facilitating the stability and consistency of subsequent imaging. The third lens has a negative refractive power and is used to correct the aberration of the entire display lens group, balance the focusing degree of the light, and facilitate control of the exit angle of the light to improve the accuracy of the imaging. At the same time, the present application sets a reflector, and realizes the optical path turning through the reflector, which is conducive to reducing the volume of the display lens group and improving its space utilization and portability. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 FIG. 1 is a schematic structural diagram of a display lens assembly in an embodiment of the present application.

[0032] Figure 2 This is a geometric diagram of the aspheric surface of the corresponding lens.

[0033] Figure 3 Schematic diagram of the structure of the display lens assembly in the second embodiment of the present application.

[0034] Figure 4 Schematic diagram of the structure of the display lens assembly in the third embodiment of the present application.

[0035] Figure 5 for Figure 1 The diagram shows the longitudinal spherical aberration of the display lens assembly.

[0036] Figure 6 for Figure 1 The astigmatism field curve diagram of the display mirror assembly is shown.

[0037] Figure 7 for Figure 1 The distortion curve of the display lens assembly is shown.

[0038] Figure 8 for Figure 3 The diagram shows the longitudinal spherical aberration of the display lens assembly.

[0039] Figure 9 for Figure 3 The astigmatism field curve diagram of the display mirror assembly is shown.

[0040] Figure 10 for Figure 3 The distortion curve of the display lens assembly is shown.

[0041] Figure 11 for Figure 4 The diagram shows the longitudinal spherical aberration of the display lens assembly.

[0042] Figure 12 for Figure 4 The astigmatism field curve diagram of the display mirror assembly is shown.

[0043] Figure 13 for Figure 4 The distortion curve of the display lens assembly is shown.

[0044] Description of Figure Numbers:

[0045] 10. Display lens assembly;

[0046] 1. First lens; 2. Second lens; 3. Third lens; 4. Image display unit; 5. Reflector; 6. Aperture;

[0047] F1, first direction; F2, second direction. DETAILED DESCRIPTION

[0048] To make the above-mentioned objects, features, and advantages of the present application more clearly understood, the specific embodiments of the present application are described in detail below with reference to the accompanying drawings. The following description sets forth many specific details to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the scope of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0049] In the description of this application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0050] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include at least one of such features. In the description of this application, if the term "plurality" appears, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0051] In this application, unless otherwise specified or limited, the terms "mounted," "connected," "connected," "fixed," etc., should be interpreted broadly. For example, these terms may refer to fixed connections, removable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediary; and internal communication between two components or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0052] In this application, unless otherwise expressly specified or limited, if a first feature is described as being "above" or "below" a second feature, or similar descriptions, this may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, when a first feature is described as being "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is described as being "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0053] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only embodiment.

[0054] Augmented reality head-up display (AR HUD) technology for automotive applications has flourished in recent years. However, the physical space available for installing AR HUD modules within vehicle dashboards is extremely limited. This rigid constraint places increasingly stringent demands on the miniaturization of the projection optics system, a core component of AR HUDs.

[0055] Specifically, as the core of the optical system, reducing the size and dimensions of the projection lens assembly is crucial. The core design challenge lies in significantly reducing the physical size of the lens while ensuring superior imaging quality, such as high resolution, low distortion, and good contrast.

[0056] Based on this, the present application provides a display lens assembly and a head-up display device, which can have a smaller size and better display effect.

[0057] See Figure 1 As shown, Figure 1 FIG. 1 is a schematic structural diagram of a display lens assembly 10 in an embodiment of the present application.

[0058] Along the optical path, the display lens assembly 10 sequentially includes a first lens 1, a reflector 5, a second lens 2, a third lens 3, and an image display unit 4. The first lens 1 has positive refractive power, which helps converge light and reduce system aberrations. This allows light to be efficiently transmitted to the reflector 5 and the second lens 2, improving image clarity and brightness.

[0059] The second lens 2 has positive refractive power, which can further optimize the transmission path of light and adjust the divergence of light, thereby cooperating with the first lens 1 to facilitate a smooth transition of light, help control high-order aberrations of light, improve imaging uniformity and color reproduction, and thus facilitate the stability and consistency of subsequent imaging.

[0060] The third lens 3 has a negative refractive power and is used to correct the aberration of the entire display lens assembly 10, balance the focusing degree of light, and help control the emission angle of light to improve the accuracy of imaging.

[0061] The image display unit 4 is configured to receive the light emitted by the third lens 3 and generate an image. The image display unit 4 of the present application may be a liquid crystal on silicon chip (LCoS chip) or a digital light processing chip (DLP chip).

[0062] The reflector 5 is disposed between the first lens 1 and the second lens 2 and is used to reflect the light emitted from the first lens 1 to the second lens 2 to achieve a light path deflection, thereby reducing the volume of the display lens assembly 10 .

[0063] The display lens assembly 10 of the present application can effectively improve the display quality of the display lens assembly 10 through the cooperation of the first lens 1, the second lens 2 and the third lens 3, and realize the optical path turning through the reflector 5, which can effectively reduce the volume of the display lens assembly 10, which is beneficial to improving the space utilization and portability of the display lens assembly 10, so that the display lens assembly 10 of the present application can have both a better miniaturized design and a better display effect.

[0064] In some embodiments, continue to refer to Figure 1As shown, the reflector 5 is disposed on one side of the first lens 1 along a first direction F1, the second lens 2 is disposed on one side of the reflector 5 along a second direction F2, and along the second direction F2, the third lens 3 and the image display unit 4 are sequentially disposed on the side of the second lens 2 facing away from the reflector 5. The first direction F1 and the second direction F2 intersect. Thus, light deflection by the reflector 5 further optimizes space utilization and facilitates a compact design of the display lens assembly 10.

[0065] In some embodiments, the first direction F1 and the second direction F2 are perpendicular to each other. This optimizes the space utilization of the display lens assembly 10 while making the light transmission path between the optical elements more reasonable, reducing light loss and interference, and improving the efficiency and stability of the optical system.

[0066] In some embodiments, the display lens assembly 10 satisfies the following relationship: 1.0 < f1 / f < 2.0, where f is the focal length of the display lens assembly 10 and f1 is the focal length of the first lens 1. Satisfying this relationship between the focal lengths of the first lens 1 and the display lens assembly 10 facilitates reasonable control of the light converging capability of the first lens 1. While minimizing the overall size of the display lens assembly 10, it ensures that the first lens 1 can effectively converge light, reducing energy loss during subsequent light transmission, thereby improving image brightness and clarity, allowing the driver to obtain a bright, clear image.

[0067] In some embodiments, the display lens assembly 10 further satisfies the relationship: 0.4 < f2 / f < 1.1, where f2 is the focal length of the second lens 2. The focal lengths of the first lens 1 and the display lens assembly 10 satisfying this relationship facilitate further convergence and adjustment of light in conjunction with the first lens 1. This effectively controls higher-order aberrations of the light while ensuring a smooth transition, resulting in more even distribution of light to subsequent optical elements. This improves imaging uniformity and color reproduction, resulting in more vivid and realistic images.

[0068] In some embodiments, the display lens assembly 10 further satisfies the following relationship: 0.1<|f3 / f|<0.6, where f3 is the focal length of the third lens 3. The focal lengths of the first lens 1 and the display lens assembly 10 satisfying this relationship facilitate precise adjustment of the light divergence capability of the third lens 3, effectively correcting aberrations and balancing focus of light transmitted through the first two lenses, or the first lens 1 and the second lens 2, thereby improving imaging accuracy and sharpness, resulting in clearer edges and richer details in the image.

[0069] In some embodiments, the display lens assembly 10 further satisfies: 0.3 < f / TTL < 0.9, where TTL is the total optical length of the display lens assembly 10. Meeting the above condition is beneficial for further controlling the overall size of the display lens assembly 10 while maintaining good imaging quality.

[0070] The total optical length TTL is the distance between the light incident surface of the aperture and the light exiting surface of the image display unit.

[0071] In some embodiments, the first lens 1, the second lens 2, and the third lens 3 are all aspherical lenses. The aspherical lens design enables the first lens 1, the second lens 2, and the third lens 3 to have better light control capabilities, effectively reduce aberrations, improve image quality, and provide greater advantages in miniaturization, helping to achieve the high performance and compactness goals of the display lens assembly 10.

[0072] In some embodiments, see Figure 1 , combined with reference Figure 2 As shown, the light incident surface of the first lens 1, the light exit surface of the first lens 1, the light incident surface of the second lens 2, the light exit surface of the second lens 2, the light incident surface of the third lens 3, and the light exit surface of the third lens 3 all satisfy the following formula:

[0073] ...Surface formula of aspheric surface;

[0074] Where Z is the depth of the preset point on the corresponding aspheric surface of the corresponding lens along the optical axis, Y is the distance between the preset point and the optical axis, R is the curvature radius of the corresponding aspheric surface of the corresponding lens, K is the cone constant, and a 2i is the 2i-order aspheric coefficient.

[0075] By using the above formula, the aspheric surface shapes of different lenses can be accurately designed, thereby optimizing the transmission and focusing characteristics of light and further improving the imaging quality of the display lens assembly 10 .

[0076] The present application may adopt the display lens assembly 10 having the parameters described in the following three embodiments.

[0077] Example 1:

[0078] See Figure 1 As shown in Table 1 below, in this embodiment, the aperture value of the display lens assembly 10 is 0.913, the focal length f of the display lens assembly 10 is 118.677 mm, and the included angle θ is 39°. In this embodiment, f1 / f = 1.318, f2 / f = 0.734, |f3 / f| = 0.397, and f / TTL = 0.676. As can be seen, the present application has a relatively low aperture value, which can increase the amount of light entering and enhance the brightness of the image in low-light environments. A moderate f value enables the display lens assembly 10 to maintain a compact size while providing a sufficiently large imaging field of view. The setting of the included angle θ helps optimize the optical path design, improving the compactness and imaging quality of the overall optical system.

[0079] The radius of curvature of the light-entering surface of the first lens element 1 is 106.223mm, and the radius of curvature of the light-exiting surface is 722.486mm. The radius of curvature of the light-entering surface of the second lens element 2 is 34.324mm, and the radius of curvature of the light-exiting surface is 163.415mm. The radius of curvature of the light-entering surface of the third lens element 3 is 17.741mm, and the radius of curvature of the light-exiting surface is 23.203mm. By meeting the above conditions and rationally designing the radius of curvature of each lens element, the refraction and convergence of light can be effectively controlled, the imaging effect can be optimized, aberrations can be reduced, and image clarity and contrast can be improved.

[0080] Among them, the light-emitting surface of the first lens 1 is a convex surface. In this application, the convex surface and the concave surface are defined relative to the corresponding lens itself, and will not be repeated here.

[0081] In this embodiment, along the optical axis, the following design requirements are met: the thickness of the aperture 6 is 2.75 mm, the spacing between the first lens 1 and the aperture 6 is 29.179 mm, the thickness of the first lens 1 is 51.5 mm, the spacing between the reflector 5 and the first lens 1 is 66 mm, the spacing between the second lens 2 and the reflector 5 is 2.2 mm, the thickness of the second lens 2 is 4.73 mm, the spacing between the third lens 3 and the second lens 2 is 14.73 mm, and the thickness of the second lens 2 is 4.266 mm. Thus, the display lens assembly 10 of the present application can maintain a relatively small lens spacing, which is beneficial for reducing the size of the display lens assembly 10 while also reducing light interference and scattering.

[0082] In this embodiment, the refractive index of the first lens element 1 is 1.594 and the Abbe number is 40.96; the refractive index of the second lens element 2 is 1.498 and the Abbe number is 58.82; and the refractive index of the third lens element 3 is 1.734 and the Abbe number is 33.08. Meeting these values ​​allows the first lens element 1, the second lens element 2, and the third lens element 3 to achieve different combinations of refractive indices and Abbe numbers, effectively controlling the dispersion and refraction of light and achieving optimal convergence of light of different wavelengths.

[0083] Table 1

[0084]

[0085] As shown in Table 2 below, in this embodiment, the incident and exit surfaces of the first lens 1, the incident and exit surfaces of the second lens 2, and the incident and exit surfaces of the third lens 3 all satisfy the aforementioned aspheric surface formula. The aspheric coefficients and conic constants of the corresponding surfaces of the corresponding lenses satisfy the requirements of Table 2 below.

[0086] Table 2

[0087]

[0088] In Table 2, surface 11 represents the incident surface of the first lens 1, surface 12 represents the exit surface of the first lens 1, surface 31 represents the incident surface of the second lens 2, surface 32 represents the exit surface of the second lens 2, surface 41 represents the incident surface of the third lens 3, and surface 42 represents the exit surface of the third lens 3.

[0089] In this embodiment, the aspheric coefficients and conic constants of the corresponding surfaces of the corresponding lenses satisfy Table 2 above, which is conducive to accurately controlling the surface shape of each surface through the parameters in Table 2, thereby further reducing aberrations and improving imaging clarity and resolution.

[0090] See Figure 1 , and then refer to Figure 5 、 Figure 6 and Figure 7 As shown, Figure 5 for Figure 1 The diagram shows the longitudinal spherical aberration of the display lens assembly. Figure 6 for Figure 1 The astigmatism field curve diagram of the display mirror assembly is shown. Figure 7 for Figure 1 The distortion curve of the display lens assembly is shown.

[0091] Figure 5 The vertical axis is the incident height of the light, in millimeters, indicating the vertical distance of the light entering the optical system from the optical axis. The horizontal axis is the defocus, indicating the offset of the actual focus position relative to the ideal focus position, in millimeters. Figure 5 , it can be seen that the abscissa of the curve takes a negative value, indicating that the display lens assembly 10 has positive spherical aberration at the paraxial position. Figure 5 The focal length offset represented by the abscissa in FIG is within 0.02 mm. It can be seen that the offset of the actual focal position relative to the ideal focal position in this embodiment is low, which can illustrate that the display lens group 10 in this embodiment has a better effect on correcting spherical aberration.

[0092] Figure 6 The vertical axis is the field of view angle in degrees, and the horizontal axis is the defocus in millimeters, which represents the offset of the actual focus position relative to the ideal focus position. The X curve (solid line) in the figure represents the meridian curve, which represents the defocus position of the meridian focal plane at different field of view angles. The Y curve (dashed line) in the figure represents the sagittal curve, which represents the defocus position of the sagittal focal plane at different field of view angles. Figure 6 As can be seen, the axial difference between the X and Y curves in this embodiment is small, resulting in less astigmatism. The display lens assembly 10 of this embodiment effectively corrects astigmatism. Furthermore, the defocus values ​​represented by the abscissas of the X and Y curves in this embodiment are both within approximately 0.05 mm, demonstrating that the display lens assembly 10 of this embodiment effectively corrects field curvature.

[0093] Figure 7 The vertical axis of the distortion curve is the field of view angle, in degrees, and the horizontal axis is the distortion rate (%), which directly reflects the trend of image distortion rate changing with the field of view angle. Figure 7 As can be seen from the figure, the overall distortion curve is relatively close to the vertical axis, and the distortion rate at each location does not exceed about 0.25%. It can be seen that the display lens assembly 10 of the present application has a good correction effect on the near-axis image distortion.

[0094] Example 2:

[0095] See Figure 3 As shown, Figure 3 FIG. 1 is a structural diagram of the display lens assembly 10 in the second embodiment of the present application.

[0096] With reference to the following Table 3, in this embodiment, the aperture value of the display lens assembly 10 is 0.902. The relatively low aperture value can increase the amount of light entering and enhance the brightness of the image in a low-light environment.

[0097] The focal length f of the display lens assembly 10 is 117.21 mm. The moderate f enables the display lens assembly 10 to provide a sufficiently large imaging field of view while maintaining a compact size.

[0098] The included angle θ is 37°, which helps to optimize the optical path design, further reduce the volume, and improve the compactness and imaging quality of the overall optical system.

[0099] The radius of curvature of the light incident surface of the first lens 1 is 118.615mm, and the radius of curvature of the light emitting surface is 1716.908mm. The light emitting surface of the first lens 1 is convex. The radius of curvature of the light incident surface of the second lens 2 is 43.841mm, and the radius of curvature of the light emitting surface is 160.257mm. The radius of curvature of the light incident surface of the third lens 3 is 20.255mm, and the radius of curvature of the light emitting surface is 25.51mm. In this embodiment, f1 / f=1.587, f2 / f=0.867, |f3 / f|=0.398, and f / TTL=0.589. In this way, the refraction and convergence of light can be effectively controlled, so that light can propagate along the expected path when passing through different lenses, reducing the generation of aberrations and improving the clarity and contrast of imaging.

[0100] In this embodiment, along the optical axis, the following design requirements are met: the thickness of the aperture 6 is 3.301 mm, the distance between the first lens 1 and the aperture 6 is 27.081 mm, the thickness of the first lens 1 is 50.888 mm, the distance between the reflector 5 and the first lens 1 is 80 mm, the distance between the second lens 2 and the reflector 5 is 2.981 mm, the thickness of the second lens 2 is 5.523 mm, the distance between the third lens 3 and the second lens 2 is 22.653 mm, and the thickness of the second lens 2 is 6.574 mm. This reduces the distance between adjacent lenses while meeting the light adjustment requirements, facilitating a compact design of the display lens assembly 10.

[0101] In this embodiment, the first lens 1 has a refractive index of 1.594 and an Abbe number of 40.96; the second lens 2 has a refractive index of 1.594 and an Abbe number of 40.96; and the third lens 3 has a refractive index of 1.734 and an Abbe number of 33.08. This combination of lenses with different refractive indices and Abbe numbers effectively controls the dispersion and refraction of light, achieving optimal convergence of light of different wavelengths, reducing chromatic aberration, and improving color reproduction and clarity of images.

[0102] Table 3

[0103]

[0104] As shown in Table 4 below, in this embodiment, the incident and exit surfaces of the first lens 1, the incident and exit surfaces of the second lens 2, and the incident and exit surfaces of the third lens 3 all satisfy the aforementioned aspheric surface formula. The aspheric coefficients and conic constants of the corresponding surfaces of the corresponding lenses satisfy the requirements of Table 4 below.

[0105] Table 4

[0106]

[0107] In Table 4, surface 11 represents the incident surface of the first lens 1, surface 12 represents the exit surface of the first lens 1, surface 31 represents the incident surface of the second lens 2, surface 32 represents the exit surface of the second lens 2, surface 41 represents the incident surface of the third lens 3, and surface 42 represents the exit surface of the third lens 3.

[0108] In this embodiment, the aspheric coefficient and conic constant of the corresponding surface of the corresponding lens meet Table 4 above, which is conducive to accurately controlling the shape of the aspheric surface, further reducing aberrations, improving imaging clarity and resolution, and achieving high-quality optical imaging effects.

[0109] See Figure 3 , and then refer to Figure 8 、 Figure 9 and Figure 10 As shown, Figure 8 for Figure 3The diagram shows the longitudinal spherical aberration of the display lens assembly. Figure 9 for Figure 3 The astigmatism field curve diagram of the display mirror assembly is shown. Figure 10 for Figure 3 The distortion curve of the display lens assembly is shown.

[0110] Figure 8 The vertical axis is the incident height of the light, in millimeters, indicating the vertical distance of the light entering the optical system from the optical axis. The horizontal axis is the defocus, indicating the offset of the actual focus position relative to the ideal focus position, in millimeters. Figure 8 , it can be seen that the horizontal coordinate of the curve takes a positive value at the paraxial position and a negative value at the non-paraxial position, indicating that the display lens assembly 10 has negative spherical aberration at the paraxial position and positive spherical aberration at the non-paraxial position. Figure 8 The focal length offset represented by the horizontal axis is within 0.002 mm, indicating that the curve at the paraxial position is relatively close to the vertical axis, and the focal length offset at the non-paraxial position is also within 0.008 mm. It can be seen that the actual focus position in this embodiment has a low offset relative to the ideal focus position, which can illustrate that the display lens assembly 10 in this embodiment has a better effect on correcting spherical aberration.

[0111] Figure 9 The vertical axis is the field of view angle in degrees, and the horizontal axis is the defocus in millimeters, which represents the offset of the actual focus position relative to the ideal focus position. The X curve (solid line) in the figure represents the meridian curve, which represents the defocus position of the meridian focal plane at different field of view angles. The Y curve (dashed line) in the figure represents the sagittal curve, which represents the defocus position of the sagittal focal plane at different field of view angles. Figure 9 As can be seen, at the paraxial position, the axial difference between the X and Y curves in this embodiment is small, resulting in less astigmatism. The display lens assembly 10 of this embodiment effectively corrects astigmatism. Furthermore, the defocus values ​​represented by the abscissas of the X and Y curves in this embodiment are both within approximately 0.02 mm, demonstrating that the display lens assembly 10 of this embodiment effectively corrects field curvature.

[0112] Figure 10 The vertical axis of the distortion curve is the field of view angle, in degrees, and the horizontal axis is the distortion rate (%), which directly reflects the trend of image distortion rate changing with the field of view angle. Figure 10 It can be seen from the figure that the distortion rate at the near axis does not exceed about 0.2%. It can be seen that the display lens assembly 10 of the present application has a good correction effect on the image distortion at the near axis. Figure 10 In the figure, the curve changes in one direction, and there are no other complex curves such as S-lines, etc., which indicates that there are no high-order aberrations in this embodiment. It can be seen that this embodiment has a better correction effect on high-order aberrations.

[0113] Example 3:

[0114] See Figure 4 As shown, Figure 4 Schematic diagram of the structure of the display lens assembly 10 in the third embodiment of the present application.

[0115] As shown in Table 5 below, in this embodiment, the aperture value of the display lens assembly 10 is 0.987. This embodiment has a moderate aperture value, which can balance the amount of light entering and aberration control. It ensures that more light enters the image under normal lighting conditions, while avoiding the aberration problem caused by an excessively large aperture 6.

[0116] The focal length f of the display lens assembly 10 is 118.408 mm. Such a moderate focal length enables the display lens assembly 10 to provide a sufficiently large imaging field of view while maintaining a compact size.

[0117] The included angle θ is 38°, which helps to further reduce the volume of the optical system and improve the compactness of the overall optical system.

[0118] The radius of curvature of the light incident surface of the first lens 1 is 95.267mm, and the radius of curvature of the light exit surface is 1942.316mm. The radius of curvature of the light incident surface of the second lens 2 is 37.243mm, and the radius of curvature of the light exit surface is 291.226mm. The radius of curvature of the light incident surface of the third lens 3 is 18.48mm, and the radius of curvature of the light exit surface is 25.537mm. In this embodiment, f1 / f=1.426, f2 / f=0.603, |f3 / f|=0.35, and f / TTL=0.646. By carefully designing the radius of curvature of each lens, the refraction and convergence path of light can be precisely controlled, so that the light can form a high-quality image after passing through the lens group, while reducing the generation of aberrations and improving the clarity and contrast of the image.

[0119] Among them, the light-emitting surface of the first lens 1 is a convex surface. In this application, the convex surface and the concave surface are defined relative to the corresponding lens itself, and will not be repeated here.

[0120] In this embodiment, along the optical axis, the following design requirements are met: the thickness of the aperture 6 is 2.908 mm, the spacing between the first lens 1 and the aperture 6 is 27.378 mm, the thickness of the first lens 1 is 48 mm, the spacing between the reflector 5 and the first lens 1 is 68 mm, the spacing between the second lens 2 and the reflector 5 is 2.44 mm, the thickness of the second lens 2 is 6.352 mm, the spacing between the third lens 3 and the second lens 2 is 19.384 mm, and the thickness of the second lens 2 is 8.519 mm. The rational layout of the optical components along the optical axis optimizes the optical path, reduces interference and scattering of the light beam during propagation, and facilitates miniaturization.

[0121] In this embodiment, the first lens element 1 has a refractive index of 1.536 and an Abbe number of 55.98; the second lens element 2 has a refractive index of 1.594 and an Abbe number of 40.96; and the third lens element 3 has a refractive index of 1.734 and an Abbe number of 33.08. This combination of lenses with different refractive indices and Abbe numbers effectively controls the dispersion and refraction of light, achieving optimal convergence of light of different wavelengths, reducing chromatic aberration, and improving image color reproduction and clarity.

[0122] Table 5

[0123]

[0124] With reference to Table 6 below, in this embodiment, the incident and exit surfaces of the first lens 1, the incident and exit surfaces of the second lens 2, and the incident and exit surfaces of the third lens 3 all satisfy the aforementioned aspheric surface formula. The aspheric coefficients and conic constants of the corresponding surfaces of the corresponding lenses satisfy the requirements of Table 6 below.

[0125] Table 6

[0126]

[0127] In Table 6, surface 11 represents the incident surface of the first lens 1, surface 12 represents the exit surface of the first lens 1, surface 31 represents the incident surface of the second lens 2, surface 32 represents the exit surface of the second lens 2, surface 41 represents the incident surface of the third lens 3, and surface 42 represents the exit surface of the third lens 3.

[0128] In this embodiment, the aspheric coefficient and conic constant of the corresponding surface of the corresponding lens meet Table 6 above, which is conducive to accurately controlling the shape of the aspheric surface, further reducing aberrations, improving imaging clarity and resolution, and achieving high-quality optical imaging effects.

[0129] See Figure 4 , and then refer to Figure 11 、 Figure 12 and Figure 13 As shown, Figure 11 for Figure 4 The diagram shows the longitudinal spherical aberration of the display lens assembly. Figure 12 for Figure 4 The astigmatism field curve diagram of the display mirror assembly is shown. Figure 13 for Figure 4 The distortion curve of the display lens assembly is shown.

[0130] Figure 11 The vertical axis is the incident height of the light, in millimeters, indicating the vertical distance of the light entering the optical system from the optical axis. The horizontal axis is the defocus, indicating the offset of the actual focus position relative to the ideal focus position, in millimeters. Figure 11It can be seen that the abscissa of the curve almost completely coincides with the ordinate axis at the paraxial position, indicating that the display lens assembly 10 has almost no spherical aberration at the paraxial position, or in other words, its focal length offset at the paraxial position is almost 0. It can be seen that its imaging quality at the paraxial position is better. In this embodiment, the display lens assembly 10 has a better effect of correcting spherical aberration at the paraxial position.

[0131] Figure 12 The vertical axis is the field of view angle in degrees, and the horizontal axis is the defocus in millimeters, which represents the offset of the actual focus position relative to the ideal focus position. The X curve (solid line) in the figure represents the meridian curve, which represents the defocus position of the meridian focal plane at different field of view angles. The Y curve (dashed line) in the figure represents the sagittal curve, which represents the defocus position of the sagittal focal plane at different field of view angles. Figure 12 As can be seen, at the paraxial position, the axial difference between the X and Y curves in this embodiment is small, resulting in less astigmatism. The display lens assembly 10 of this embodiment effectively corrects astigmatism. Furthermore, the defocus values ​​indicated by the abscissas of the X and Y curves in this embodiment are both within approximately 0.015 mm, demonstrating that the display lens assembly 10 of this embodiment effectively corrects field curvature. In particular, at the paraxial position, the defocus values ​​indicated by the abscissas of the X and Y curves are both within approximately 0.005 mm, demonstrating that the display lens assembly 10 of this embodiment effectively corrects field curvature at this position.

[0132] Figure 13 The vertical axis of the distortion curve is the field of view angle, in degrees, and the horizontal axis is the distortion rate (%), which directly reflects the trend of image distortion rate changing with the field of view angle. Figure 13 As can be seen from the figure, the curve is relatively close to the vertical axis, indicating that the distortion rate is relatively small, especially at the near axis, where the distortion rate does not exceed about 0.1%. It can be seen that the display lens assembly 10 of the present application has a good correction effect on the image distortion at the near axis.

[0133] and Figure 13 In the figure, the curve changes in one direction, and there are no other complex curves such as S-lines, etc., which indicates that there are no high-order aberrations in this embodiment. It can be seen that this embodiment has a better correction effect on high-order aberrations.

[0134] In some embodiments, as Figure 1 Reflector 5 includes a planar reflective surface, and the angle θ between the reflective surface and the axis of the second lens satisfies the following: 25° < θ < 55°. This effectively deflects light, reducing the size of display lens assembly 10 while accurately reflecting light emitted from first lens 1 to second lens 2, minimizing aberrations and energy loss that could result from excessive light deflection.

[0135] For example, the angle θ may be 27°, 30°, 45°, 50°, etc. When the angle θ is 30°, the reflector deflects the received light propagating along the first direction by 120°.

[0136] In some embodiments, continue to refer to Figure 1 As shown, at the near optical axis, the light incident surface of the first lens 1 is a convex surface. The convex light incident surface can effectively control the incident angle of the light and reduce the degree of divergence of the light when entering the lens, which is beneficial to the convergence of the light and enables the light to enter the optical system more concentratedly.

[0137] At the near optical axis, the light incident surface of the second lens 2 is concave, and the light emitting surface is convex. The concave light incident surface can make appropriate divergence adjustments to the light, balancing the over-focusing phenomenon that may occur after the first lens 1 converges the light. This can prevent the light from being too concentrated on one point and ensure that the light can be evenly distributed to the subsequent optical elements. The design of the light emitting surface as a convex surface can converge the light again to ensure that the light can be transmitted to the third lens 3 along a suitable path. This combination of concave and convex design is conducive to optimizing the transmission path of light, reducing the divergence of light, making the light more evenly distributed to the subsequent optical elements, and improving the uniformity of imaging and color reproduction.

[0138] At the near optical axis, the third lens element 3 has a convex light-entry surface and a concave light-exit surface. The convex light-entry surface facilitates further convergence and correction of light, optimizing its focus and enabling accurate projection onto the image display unit 4. The concave light-exit surface appropriately adjusts the divergence of light, ensuring uniform coverage of the entire active area of ​​the image display unit 4. This avoids image unevenness caused by excessive light concentration or divergence, thereby improving imaging accuracy and sharpness.

[0139] In some embodiments, continue to refer to Figure 1 The display lens assembly 10 shown also includes an aperture 6, which is disposed on the side of the first lens 1 facing away from the reflector 5. The aperture 6 can control the amount of light entering the optical system, adjust the depth of field and contrast of the image, and further optimize the image quality, making the image clearer and sharper.

[0140] The present application also provides a head-up display device, comprising the display lens assembly 10 of any of the above embodiments. The head-up display device of the present application can provide the driver with high-quality image display while driving a vehicle, and occupies less space in the vehicle.

[0141] The display lens assembly 10 and head-up display device of the present application, through the combination of the first lens 1, the second lens 2, and the third lens 3, effectively converges and controls light, reducing aberrations and thus providing high-resolution and clear images. The rationally set focal length ratio of each lens further optimizes light transmission, ensuring image detail and sharpness. Furthermore, the combination of the first lens 1, the second lens 2, and the third lens 3 with different refractive indices and Abbe numbers effectively controls light dispersion, achieving optimal convergence of light of different wavelengths, reducing chromatic aberration, and resulting in vibrant, realistic images. Furthermore, the aspheric design improves imaging contrast and enhances image clarity. Furthermore, the reflector 5 achieves optical path deflection, optimizing space utilization. The intersecting design of the first direction F1 and the second direction F2, particularly the perpendicular design, optimizes the light transmission path between the optical components, further reducing the size of the display lens assembly 10. By limiting the ratio of the total optical length to the focal length of the display lens assembly 10 to a certain range, the display lens assembly 10 is miniaturized, facilitating the miniaturization of the head-up display device.

[0142] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0143] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A display lens assembly, characterized in that: Along the propagation direction of the light path, the display mirror assembly includes: A first lens having positive refractive power; a second lens having positive refractive power; a third lens having negative refractive power; an image display unit, configured to receive the light passing through the third lens and generate an image; and The reflector is disposed between the first lens and the second lens and is used to reflect the light emitted by the first lens to the second lens.

2. The display lens assembly according to claim 1, characterized in that: The reflector is provided on one side of the first lens along the first direction, the second lens is provided on one side of the reflector along the second direction, and along the second direction, the third lens and the image display unit are provided in sequence on the side of the second lens away from the reflector; The first direction and the second direction intersect with each other.

3. The display lens assembly according to claim 1, characterized in that: The display lens assembly satisfies: 1.0<f1 / f<2.0; 0.4<f2 / f<1.1; 0.1<︱f3 / f︱<0.6; Wherein, f is the focal length of the display lens assembly, f1 is the focal length of the first lens, f2 is the focal length of the second lens, and f3 is the focal length of the third lens.

4. The display lens assembly according to claim 1, characterized in that: The display lens assembly also satisfies: 0.3<f / TTL<0.9; Wherein, f is the focal length of the display lens assembly, and TTL is the total optical length of the display lens assembly.

5. The display lens assembly according to claim 1, characterized in that: The first lens, the second lens, and the third lens are all aspherical lenses.

6. The display lens assembly according to claim 5, characterized in that: The display lens assembly also satisfies: 1.0<|R1 / R2|<5.0; 0.5<|R2 / R3|<4.0; Among them, R1 is the curvature radius of the light incident surface of the first lens at the paraxial position, R2 is the curvature radius of the light incident surface of the second lens at the paraxial position, and R3 is the curvature radius of the light incident surface of the third lens at the paraxial position.

7. The display lens assembly according to claim 1, characterized in that: The reflector includes a reflective surface, the reflective surface is a plane, and an angle θ between the reflective surface and the axis of the second lens satisfies: 25°<θ<55°.

8. The display lens assembly according to claim 1, characterized in that: At the near optical axis, the light incident surface of the first lens is convex, and the light exit surface is convex; the light incident surface of the second lens is concave, and the light exit surface is convex; the light incident surface of the third lens is convex, and the light exit surface is concave.

9. The display lens assembly according to claim 1, characterized in that: The display lens assembly further includes an aperture, which is arranged on a side of the first lens away from the reflector.

10. A head-up display device, characterized in that: The display lens assembly comprises the display lens assembly according to any one of claims 1 to 9.

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