Optical element, head-up display system, and vehicle

Abstract

The present disclosure relates to the technical field of head-up displays, in particular to an optical element, a head-up display, and a vehicle. The optical element comprises a base lens, which is a sheet-shaped lens, and a direction control unit and a dispersion unit are arranged on the base lens. The directional control and the dispersion effect of an optical path can be achieved by means of one optical element, the space occupied by the optical element is reduced, and therefore the overall size of the head-up display can be conveniently controlled; in addition, the cost of the optical element can be reduced.

Description

Optical components, head-up display systems and vehicles Technical Field

[0001] The present disclosure relates to the technical field of head-up displays, and in particular to an optical element, a head-up display system, and a vehicle. Background Art

[0002] A HUD (head-up display), also known as a head-up display, projects light from the HUD's image source onto an imaging window (such as a rear-mounted imaging board or the vehicle's windshield), allowing users to see the image directly without having to lower their heads, thereby improving the user experience. For example, in some situations, this can prevent drivers from being distracted by looking down at the dashboard while driving, thereby improving driving safety and providing a better driving experience.

[0003] Generally speaking, a head-up display system includes a head-up display and a reflective imaging module. In order to improve the display effect of the HUD, the image source display module of the HUD generally includes two parts: a diffusion element and a direction control element. This results in a complex optical path, occupies a large space, and causes the overall volume of the HUD to be larger.

[0004] Summary of the Invention

[0005] In order to solve the above technical problems or at least partially solve the above technical problems, the present disclosure provides an optical element, a head-up display system and a vehicle.

[0006] The present disclosure provides an optical element, including a base lens, wherein the base lens is a sheet lens, and a direction control unit and a diffusion unit are provided on the base lens.

[0007] In some examples, the direction control unit and the diffusion unit are both integrated on the base lens and are configured to adjust the angle of the incident light and diffuse it.

[0008] In some examples, the direction control unit and the diffusion unit are configured as an integrated structural unit, the integrated structural unit includes a microlens array; and the microlens array is provided on at least one side of the base lens.

[0009] In some examples, the microlens array is a cylindrical microlens array, and each cylindrical microlens in the cylindrical microlens array has a deflection angle for incident light, and the deflection angle is determined by a focal length f and an eccentric distance d of the cylindrical microlens.

[0010] In some examples, the cylindrical microlens array includes a first lens layer and a second lens layer, wherein the first lens layer and the second lens layer are disposed on the same side of the base lens; or, the first lens layer and the second lens layer are respectively disposed on two opposite sides of the base lens.

[0011] In some examples, the first lens layer includes a plurality of first cylindrical lenses continuously arranged along a first direction, and the light-emitting surfaces of at least some of the first cylindrical lenses are eccentric arc-shaped surfaces. The second lens layer includes a plurality of second cylindrical lenses continuously arranged along a second direction, and the light-emitting surfaces of at least some of the second cylindrical lenses are eccentric arc-shaped surfaces. There is an angle between the second direction and the first direction.

[0012] In some examples, the first direction is perpendicular to the second direction.

[0013] In some examples, the microlens array is a spherical microlens array, and each of the spherical microlens in the spherical microlens array has a deflection angle for incident light, and the deflection angle is determined by the focal length f and the eccentric distance d of the spherical microlens.

[0014] In some examples, the spherical microlens array is provided on a side surface of the base lens, the spherical microlens array includes a plurality of spherical microlenses, and the light-emitting surfaces of at least some of the spherical microlenses are eccentric arc-shaped surfaces.

[0015] In some examples, the aperture of each microlens in the microlens array is greater than or equal to 500 nm and less than or equal to 500 um;

[0016] When the microlens is a cylindrical microlens, the aperture is the width of the cylindrical lens;

[0017] When the microlens is a spherical microlens, the aperture includes a radial dimension of the spherical microlens along a third direction or a radial dimension along a fourth direction, and the third direction is perpendicular to the fourth direction.

[0018] In some examples, the light-emitting surface of each microlens in the microlens array is convex or concave.

[0019] In some examples, the deflection angle ranges from greater than or equal to -30 degrees to less than or equal to +30 degrees.

[0020] In some examples, the direction control unit and the diffusion unit are respectively disposed on two opposite sides of the base lens.

[0021] In some examples, the diffusion unit is configured as a diffusion microlens array or a Saier pattern, and the direction control unit is configured as a direction control lens array.

[0022] The present disclosure also provides a head-up display system, comprising

[0023] The image source is used to emit image light, and the image source includes a backlight device, a light processing device and a display screen. The light processing device includes an optical element as described in any one of the above items, and the optical element is arranged in the light path between the backlight device and the display screen;

[0024] A reflecting device reflects the image light to the eye box area to form a virtual image.

[0025] Optionally, the backlight device includes a backlight lamp board, which includes a mounting substrate, multiple backlight lamps and a driving board. The backlight lamps are mounted on the mounting substrate, and the driving board is electrically connected to the backlight lamps. The driving board or the mounting substrate is provided with a wiring circuit, and the multiple backlight lamps are respectively connected to the corresponding wiring circuits so as to independently control the brightness of at least part of the backlight lamps through the driving board.

[0026] The present disclosure also provides a vehicle comprising the above-mentioned head-up display system. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0028] In order to more clearly illustrate the embodiments of the present disclosure 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, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0029] Figure 1 is a schematic diagram of a decentered lens.

[0030] FIG. 2 is a top view of an optical element according to some embodiments of the present disclosure.

[0031] FIG3 is a left side view of FIG1 .

[0032] FIG. 4 is a top view of an optical element according to some embodiments of the present disclosure.

[0033] FIG5 is a right side view of FIG4.

[0034] FIG6 is a perspective view of the optical element according to some embodiments of the present disclosure.

[0035] FIG. 7 is a top view of optical elements according to other embodiments of the present disclosure.

[0036] FIG8 is a front view of an optical element according to some other embodiments of the present disclosure.

[0037] FIG9 is a left side view of optical elements according to other embodiments of the present disclosure.

[0038] FIG10 is a perspective view of the optical element according to some other embodiments of the present disclosure.

[0039] FIG11 is a schematic structural diagram of a head-up display system according to some embodiments of the present disclosure.

[0040] FIG12 is a schematic structural diagram of the optical element having a cylindrical lens array according to some embodiments of the present disclosure, wherein the cylindrical surface is convex.

[0041] FIG13 is a schematic structural diagram of the optical element having a cylindrical lens array according to some embodiments of the present disclosure, wherein the cylindrical surface is convex.

[0042] FIG14 is a schematic structural diagram of the optical element having a cylindrical lens array according to some embodiments of the present disclosure, wherein the cylindrical surface is concave.

[0043] FIG15 is a schematic structural diagram of the optical element having a cylindrical lens array according to some embodiments of the present disclosure, wherein the cylindrical surface is concave.

[0044] FIG16 is a schematic structural diagram of a head-up display system according to some embodiments of the present disclosure.

[0045] Among them, 1. base lens; 2. first cylindrical lens; 3. second cylindrical lens; 4. spherical microlens; 10. transflective film; 20. windshield; 30. image source; 40. virtual image; 100. backlight device; 200. collimating lens; 300. direction control diffusion element; 400. display screen; 500. first reflector; 600. second reflector; 700. reflection device; 800. eye box area. DETAILED DESCRIPTION

[0046] In order to more clearly understand the above-mentioned objectives, features and advantages of the present disclosure, the scheme of the present disclosure will be further described below. It should be noted that the embodiments of the present disclosure and the features therein can be combined with each other in the absence of conflict.

[0047] In the following description, many specific details are set forth to facilitate a full understanding of the present disclosure, but the present disclosure may also be implemented in other ways different from those described herein; it is obvious that the embodiments in the specification are only part of the embodiments of the present disclosure, rather than all of the embodiments.

[0048] Figure 1 shows the principle diagram of directional control for an eccentric lens, where D is the aperture of the eccentric lens, d is the eccentric distance, f is the focal length, and θ is the eccentric angle. The deflection angle θ is determined by the focal length f and the eccentric distance d: angle θ = artan(d / f). By designing the focal length f and the eccentric distance d, the angle of the outgoing light from the eccentric lens can be controlled. The eccentric lens deflects directly incident light at an angle between -30 and +30 degrees.

[0049] The disclosed embodiments provide an optical element comprising a base lens, wherein the base lens is a sheet-like lens and is provided with a direction control unit and a diffusion unit. The direction control unit controls the direction of light emission, and the diffusion unit diffuses the light. This allows both directional control of the light path and a diffusion effect to be achieved with a single optical element, reducing the space occupied by the optical element, thereby facilitating control of the overall volume of the head-up display and reducing the cost of the optical element.

[0050] What needs to be understood here is that the function of diffusion is to make the emitted light beam form a uniform light spot, that is, to make the brightness of the emitted light beam relatively uniform within the preset lateral diffusion angle range and longitudinal diffusion angle range.

[0051] The sheet lens in the embodiment of the present disclosure refers to a plate-shaped substrate, which includes but is not limited to a glass base or a polymer material base. The entire substrate can be of uniform thickness, thereby ensuring consistent light loss of light emitted through the glass base, thereby ensuring precise control of light.

[0052] In some examples, the direction control unit and the diffusion unit are integrated into the base lens and are configured to adjust the angle and diffuse the incident light. In other words, the direction control unit, the diffusion unit, and the base lens are all formed into an integrated structure, with no spacing between them. This not only reduces the size of the optical components but also effectively reduces light loss.

[0053] In one example, the direction control unit can employ a microlens array, which can be reused as a diffusion unit. This microlens array is provided on at least one side of the base lens of the disclosed embodiment. In other words, the microlens array of the disclosed embodiment can both control the direction of light and diffuse it. This helps improve the production efficiency of optical components and reduce their production costs.

[0054] In other words, the direction control unit and the diffusion unit in the embodiment of the present disclosure are configured as an integrated structural unit, which is configured as a microlens array, and the microlens array is provided on at least one side of the base lens. This integrated structural unit can achieve both direction control of the incident light and a diffusion effect.

[0055] In some examples, as shown in Figures 12 to 15, the integrated structural unit (i.e., the microlens array) is configured as a cylindrical microlens array, which includes a plurality of cylindrical microlenses arranged in an array, each cylindrical microlens having a deflection angle to the incident light, and the deflection angle is determined by the focal length f and the eccentric distance d of the cylindrical microlens. For example, the deflection angle θ = artan (d / f). Thus, by adjusting the focal length f and the eccentric distance d of the cylindrical microlens, a suitable deflection angle can be obtained, thereby controlling the direction of the incident light of the optical element, so that a preset deflection angle is generated between the incident light and the outgoing light. At the same time, by setting up a cylindrical microlens array, a diffusion effect of light can be achieved.

[0056] In one example, Figures 12 and 13 show schematic diagrams of an eccentric convex cylindrical lens array design, and Figures 14 and 15 show schematic diagrams of an eccentric concave cylindrical lens array design. It should be noted that in the disclosed embodiments, the so-called "convex surface" refers to an arcuate surface that bulges away from the plane where the base lens is located, with the plane where the base lens is located as the reference plane; the so-called "concave surface" refers to an arcuate surface that bulges toward the plane where the base lens is located, with the plane where the base lens is located as the reference plane.

[0057] In some examples, as shown in Figures 2 to 6, when the direction control unit and the diffusion unit are provided as a microlens array having an integral structural unit, and the microlens array is a cylindrical microlens array, cylindrical microlens arrays may be provided on two opposite sides of the base lens 1 along its thickness direction, or multiple cylindrical microlens arrays may be provided on one side of the base lens 1 along its thickness direction. The optical element of the disclosed embodiment achieves directional control of incident light in different directions through multiple cylindrical lens arrays.

[0058] For example, the optical element is provided with a single-layer cylindrical microlens array. As shown in Figures 2 and 3, in some embodiments, the optical element includes a base lens 1 and a microlens array composed of first cylindrical lenses 2. As shown in Figures 4 and 5, in other embodiments, the optical element includes a base lens 1 and a microlens array composed of second cylindrical lenses 3. As shown in Figure 6, the optical element is provided with a double-layer cylindrical microlens array. The optical element includes a base lens 1 and two layers of cylindrical microlens arrays arranged opposite each other along the thickness direction of the base lens 1. One layer of the microlens array is composed of the first cylindrical lenses 2, and the other layer of the microlens array is composed of the second cylindrical lenses 3. The extension direction of the first cylindrical lenses 2 and the extension direction of the second cylindrical lenses 3 are perpendicular to each other.

[0059] In the embodiment of the present disclosure, taking the optical element including two cylindrical microlens arrays as an example, for the convenience of description, the two cylindrical lens arrays are respectively referred to as a first lens layer and a second lens layer.

[0060] Specifically, in some examples, referring to FIG6 , the first lens layer and the second lens layer are respectively arranged on two side surfaces of the base lens that are arranged opposite to each other along the thickness direction. For ease of understanding, the cylindrical lens array located on the upper surface of the base lens 1 is referred to as the first lens layer, and the cylindrical lens array located on the lower surface of the base lens 1 is referred to as the second lens layer. The first lens layer can control the deflection angle of the outgoing light of the optical element in one direction, and the second lens layer can control the deflection angle of the outgoing light of the optical element in another direction. For example, the first lens layer can control the first deflection angle of the outgoing light in the horizontal direction, and the second lens layer can control the second deflection angle of the outgoing light in the vertical direction. By setting the first lens layer and the second lens layer, the deflection angle of the outgoing light can be adjusted in two-dimensional directions, respectively, thereby controlling the propagation direction of the light in three-dimensional space.

[0061] In another example, the first lens layer and the second lens layer are both arranged on the same layer of the base lens 1 along its thickness direction. In the embodiment disclosed herein, only the example of the first lens layer and the second lens layer being both arranged on the upper surface of the base lens 1 is taken. In this example, the extension direction of the cylindrical microlenses in the first lens layer and the extension direction of the cylindrical microlenses in the second lens layer intersect. Among them, the first lens layer can control the deflection angle of the outgoing light of the optical element in one direction, and the second lens layer can control the deflection angle of the outgoing light of the optical element in another direction. For example, the first lens layer can control the first deflection angle of the outgoing light in the horizontal direction, and the second lens layer can control the second deflection angle of the outgoing light in the vertical direction. By setting the first lens layer and the second lens layer, the deflection angle of the outgoing light can be adjusted in the two-dimensional direction, thereby controlling the propagation direction of the light in three-dimensional space.

[0062] In some embodiments of the present disclosure, a cylindrical microlens array includes a first lens layer and a second lens layer, wherein the first lens layer is disposed on one side of a base lens, and the second lens layer is disposed on the same side or opposite side of the base lens. The superposition of the first lens layer and the second lens layer enables the direction of incident light to be controlled in different directions. For example, the first lens layer can control the deflection angle of the optical element in one direction, and the second lens layer can control the deflection angle of the optical element in another direction. For example, the first lens layer can control the first deflection angle of the outgoing light in the horizontal direction, and the second lens layer can control the second deflection angle of the outgoing light in the vertical direction. By arranging the first lens layer and the second lens layer, the deflection angle of the outgoing light can be adjusted in two dimensions, thereby controlling the propagation direction of the light in three-dimensional space. For example, when the first lens layer and the second lens layer are disposed on the same side of the base lens, the first lens layer and the second lens layer can be intersected, and the structure after the intersection of the two can be disposed on the surface of the base lens 1. Alternatively, for example, when the first lens layer and the second lens layer are disposed on opposite sides of the base lens, the first lens layer can be disposed on one side of the base lens 1, and the second lens layer can be disposed on the other side of the base lens 1.

[0063] Further, referring to FIG. 6 , for any of the above examples, the first lens layer includes a plurality of first cylindrical lenses 2 arranged continuously along a first direction, and the light exit surfaces of at least some of the first cylindrical lenses 2 are eccentrically curved surfaces. The second lens layer includes a plurality of second cylindrical lenses 3 arranged continuously along a second direction, and the light exit surfaces of at least some of the second cylindrical lenses 3 are eccentrically curved surfaces. The second direction and the first direction have an angle. For example, the light exit surfaces of the first cylindrical lenses 2 are convex or concave, and the eccentric angle of the convex or concave surface of the light exit surface of the first cylindrical lens 2 is controlled by setting the eccentric angle. In other words, the focal length f and eccentric distance d of the first cylindrical lens 2 are used to control the deflection angle of the light in the first direction. Similarly, the light exit surface of the second cylindrical lens 3 is also convex or concave, and the eccentric angle of the convex or concave surface of the light exit surface of the second cylindrical lens 3 is used to control the eccentric angle of the light path in the second direction. In other words, the deflection angle of the light in the second direction is controlled by utilizing the focal length f and eccentric distance d of the second cylindrical lens 3. Since there is an angle between the first direction and the second direction, the light path passes through the superposition of the first cylindrical lens 2 and the second cylindrical lens 3, achieving directional control in a two-dimensional angle.

[0064] It should be noted that the light-emitting surfaces of the multiple first cylindrical lenses 2 of the first lens layer can be continuous convex surfaces or continuous concave surfaces, or have both convex and concave surfaces. The outer surfaces of the multiple second cylindrical lenses 3 of the second lens layer can also be continuous convex surfaces or continuous concave surfaces, or have both convex and concave surfaces. As long as the superposition of the first lens layer and the second lens layer can obtain the desired emission direction of the light path, it will be sufficient.

[0065] Furthermore, in some examples, the first direction and the second direction are perpendicular. For example, the first direction is the X direction and the second direction is the Y direction. The first lens layer and the second lens layer are used to control the eccentricity of the light path in the X and Y directions, thereby controlling the direction of the light path's output angle in two dimensions.

[0066] Furthermore, because the direction control unit and the diffusion unit in the aforementioned optical element are configured as a microlens array as an integrated structural unit, the microlens array can not only adjust the direction of light but also diffuse the light. In some examples, when the microlens array employs an upper cylindrical microlens array, the light-emitting surface of the cylindrical microlens array is a micro-transparent surface, serving as a diffusion unit to diffuse the incident light.

[0067] Specifically, when the cylindrical microlens array includes a first lens layer and a second lens layer, the light exit surface or light entrance surface of the first lens layer and the second lens layer is a micro-transparent surface, which serves as a diffusion unit to diffuse the incident light. Taking the example of the first lens layer including a plurality of first cylindrical lenses arranged continuously along a first direction and the second lens layer including a plurality of first cylindrical lenses arranged continuously along a second direction, when the first lens layer and the second lens layer are respectively arranged on two opposite side surfaces of the base lens 1 along its thickness direction, the light exit surface of the first cylindrical lens 2 and the light entrance surface of the second cylindrical lens 3 are both set as micro-transparent surfaces to achieve a diffusion effect. When the first lens layer and the second lens layer are both arranged on the same side of the base lens 1 along its thickness direction, the light exit surface of the first cylindrical lens 2 and the light exit surface of the second cylindrical lens 3 are both set as micro-transparent surfaces to achieve a diffusion effect.

[0068] For example, the first lens layer and the second lens layer can be arranged on the same side or opposite sides of the base lens 1. When the first lens layer and the second lens layer are arranged on the same side of the base lens 1, the structures of the first lens layer and the second lens layer can overlap. When the first lens layer and the second lens layer are arranged on the same side of the base lens 1, the surface of the lens layer can be formed into a micro-transparent surface by controlling the size of the cylindrical lenses to achieve a diffusion effect. When the first lens layer and the second lens layer are arranged on opposite sides of the base lens 1, the first lens layer and the second lens layer are respectively arranged on two surfaces of the base lens 1. Similarly, the surface of the lens layer can be formed into a micro-transparent surface by controlling the size of the cylindrical lenses to achieve a diffusion effect.

[0069] In some examples, the materials of the first lens layer and the second lens layer can be selected from PC plastic, glass, or photoresist, and the material of the base lens 1 can be selected from PC plastic or glass, etc.

[0070] In some examples, the eccentricity angle of each first cylindrical lens 2 and each second cylindrical lens 3 can be independently designed as needed. The deflection angle of the first cylindrical lens 2 and the second cylindrical lens 3 is mainly determined by the focal length f and the eccentricity distance d of the lens. The size of each first cylindrical lens 2 and each second cylindrical lens 3 can be the same or different.

[0071] In some examples, the direction control unit and the diffusion unit in the embodiment of the present disclosure are set as an integrated structural unit, and the integrated structural unit is set as a microlens array, as shown in Figures 7 to 10. The microlens array can specifically be a spherical microlens array, and each spherical microlens in the spherical microlens array has a deflection angle to the incident light, and the deflection angle is determined by the focal length f and the eccentric distance d of the spherical microlens. It should be understood here that the deflection angle of the spherical microlens to the incident light is in a two-dimensional direction, so the spherical microlens array can be set on one side of the base lens. The spherical microlens array includes a plurality of spherical microlenses, and the light-emitting surface of at least some of the spherical microlenses is an eccentric spherical surface. Therefore, the eccentric angle of the light path in the two-dimensional direction can be controlled by controlling the eccentric angle of the spherical surface of the light-emitting surface of the spherical microlens. In other words, the deflection angle of the light in the two-dimensional direction is controlled by using the focal length f and the eccentric distance d of the spherical microlens.

[0072] In some examples, the light-emitting surface of the spherical microlens is an eccentric curved surface with a convex or concave center. From the appearance, each spherical microlens is a convex eccentric bulge or an eccentric pit. Each spherical microlens can control the emission direction of the light path at multiple angles. The shape of the spherical microlens' orthographic projection can be rectangular or circular, and multiple spherical microlenses are evenly distributed on the base lens 1. In this embodiment, as shown in Figure 7, multiple spherical microlenses 4 are arranged on the same side of the base lens 1. The spherical microlens 4 can achieve both direction control and diffusion effect. By controlling the size of the spherical microlens 4 in the X and Y directions, as well as the light deflection angle, the shape and size of the uniform light spot after the light path is diffused can be controlled. By controlling the degree of eccentricity of the spherical microlens 4, the emission direction of the outgoing light can be controlled. That is, the deflection angle is controlled by controlling the focal length f and the eccentric distance d of the spherical microlens.

[0073] It should be noted that the light-emitting surface of each spherical microlens 4 can be a convex surface or a concave surface, or a combination of convex and concave surfaces, as long as the desired light-emitting direction can be obtained.

[0074] It should be understood that the lens names such as “cylindrical lens” or “spherical microlens” mentioned above are for the convenience of description and do not impose specific limitations on the structure described in the present disclosure.

[0075] Furthermore, the aperture of each microlens in the microlens array is greater than or equal to 500 nm and less than or equal to 500 μm. When the microlens is a cylindrical microlens, the aperture of the microlens is the width of the cylindrical lens, such as Dx in FIG3 or Dy in FIG5 . When the microlens is a spherical microlens, the aperture of the microlens includes the radial dimension of the spherical microlens along the third direction or the radial dimension along the fourth direction, where the third direction is perpendicular to the fourth direction. For example, in FIG7 and FIG8 , the apertures in the x-direction and y-direction are Dx and Dy, respectively.

[0076] Furthermore, the deflection angle of the microlenses in the microlens array ranges from greater than or equal to -30 degrees to less than or equal to 30 degrees. In other words, the optical element deflects incident light at an angle between -30 degrees and +30 degrees. This allows for precise control of the light's deflection angle.

[0077] In some examples, the diffusion unit and the direction control unit are not integrally structured, but are independent structural units. The diffusion unit and the direction control unit can be disposed on the same side or opposite sides of the base lens 1. For example, the direction control unit and the diffusion unit can be disposed on two opposite sides of the base lens 1 along the thickness direction.

[0078] In some embodiments, the direction control unit is configured as a direction control lens array, which is used to control the emission direction of light passing through the optical element; the diffusion unit is configured as a diffusion lens array or a Saier pattern, which is used to make the light passing through the optical element produce a diffusion effect, so that the incident light beam is formed into a light spot of a certain shape.

[0079] Furthermore, in some other embodiments of the present disclosure, the direction-control lens array includes a plurality of Fresnel lenses arranged in an array. A Fresnel lens is a special optical lens whose surface profile includes annular steps, which allows a certain focal length to be achieved while significantly reducing the lens thickness. This reduction in thickness is very useful when implementing lenses with very large diameters and large refractive powers. While the characteristics of Fresnel lenses are utilized to reduce the overall thickness of optical components, the deflection effect can also be achieved through structural design of the Fresnel lenses.

[0080] Furthermore, in some embodiments of the present disclosure, the diffusion unit includes a Saill pattern formed on the base lens 1 by etching, that is, the diffusion effect on the light path is achieved by providing the Saill pattern.

[0081] It should be noted that, in the embodiments of the present disclosure, the light path can be diffused by providing a micro-transparent surface on the surface of the direction control unit or the surface of the base lens 1, or by providing Saier patterns on the base lens 1.

[0082] Furthermore, in some embodiments of the present disclosure, a head-up display system is also provided, which includes a head-up display, the head-up display includes an image source, the image source is used to emit image light, the image source includes a backlight device, a light processing device and a display screen, the light processing device includes the above-mentioned optical element, and the optical element is arranged in the light path between the backlight device and the display screen; the head-up display system also includes a reflection device, the reflection device reflects the image light to the eye box area to form a virtual image.

[0083] For example, as shown in FIG16 , the backlight light emitted by the backlight device 100 is collimated by the collimating lens 200 and then incident on the direction-controlling diffusion element 300 (optical element). The light then enters the display screen 400 (such as an LCD) to form an image light. The image light is then processed by an intermediate optical path element (such as a folding process of a first reflector 500 and a second reflector 600) and then enters the reflecting device 700 (such as a windshield provided with a transflective film). After reflection by the reflecting device, the light enters the eye box area 800 where the human eye is located to form a virtual image.

[0084] In some embodiments, the backlight device includes a backlight board, which includes a mounting substrate, multiple backlights and a driving board. The backlights are mounted on the mounting substrate, and the driving board is electrically connected to the backlights. The driving board or the mounting substrate is provided with a wiring circuit, and the multiple backlights are respectively connected to the corresponding wiring circuits so that the brightness of at least part of the backlights can be independently controlled through the driving board.

[0085] For example, a head-up display (HUD) includes a backlight device and an image generation unit. The backlight device includes multiple backlights. The image generation unit includes a display panel. The display panel includes multiple display areas, and the multiple display areas correspond one-to-one to the multiple backlights. The control module determines the brightness information corresponding to each display area based on the image to be displayed on the display panel; determines the target brightness corresponding to each backlight based on the brightness information corresponding to each display area; and controls each backlight based on the target brightness corresponding to each backlight. When displaying, the HUD provided by the present disclosure determines the target brightness corresponding to each backlight based on the image to be displayed, and controls the backlight based on the target brightness. By controlling each backlight individually, light waste caused by lighting all backlights is avoided, power consumption is reduced, and light utilization and image contrast are improved.

[0086] For example, based on the distribution of the display content in each display area of ​​the image to be displayed, the display area of ​​the display panel can be divided into dark areas and bright areas. The dark areas are display areas with low display brightness (or no display content), and the bright areas are display areas with high display brightness (or display content). The brightness information corresponding to the bright and dark areas is different, and the target brightness of the backlight determined based on the brightness information is also different, thereby achieving separate control of the backlight of the dark and bright areas of the image. Due to the different backlight brightness of the dark and bright areas, the image contrast can be improved, and the contrast of the virtual image formed by the head-up display is also improved. At the same time, reducing the brightness of the backlight corresponding to the dark area or turning off the backlight in the dark area can also reduce the backlight power consumption, thereby reducing the overall power consumption of the display panel.

[0087] For example, based on the image to be displayed on the display panel, a pixel group corresponding to each display area is determined, where each pixel group includes multiple pixels. Specifically, the image to be displayed is composed of multiple pixels, each pixel displays a color. Based on the distribution of the display content in the image to be displayed in each display area, the pixel group in the image to be displayed corresponding to each display area, that is, the multiple pixels in the image to be displayed corresponding to each display area, can be determined. The display panel includes multiple pixel units, each pixel unit corresponds to a set of three primary color filters, and one pixel in the image to be displayed corresponds to one pixel unit on the display panel.

[0088] For example, as shown in FIG9 , a head-up display system includes a head-up display and a reflective device. The reflective device is located on the light-emitting side of an image source 30 of the head-up display and is configured to reflect image light emitted by the image source 30 toward the eyebox area of ​​the head-up display. This allows a user, when both eyes are located in the eyebox area, to view a virtual image 40 formed at an imaging position outside the reflective device. The reflective device includes a windshield 20 and a transflective film 10.

[0089] For example, the head-up display utilizes a reflective device to reflect the outgoing light of the image source 30, so that the observer can simultaneously observe the virtual image formed outside the reflective device and the object outside the reflective device in the eye box area. When displaying, the head-up display system provided by the embodiment of the present disclosure can individually control each backlight for the image to be displayed, thereby avoiding turning on all backlights and turning on only some backlights, and the luminous brightness of each backlight can also be independently controlled. By controlling the backlights of different areas corresponding to the image to be displayed, some backlights can be turned off and other backlights can be turned on, thereby improving the image contrast, thereby improving the contrast of the virtual image formed by the head-up display, and at the same time, the power consumption of the head-up display can be reduced by turning off some backlights or reducing the brightness of some backlights.

[0090] For example, the eye box area can be a preset area where the observer needs to view the image according to actual needs, that is, the eye box area (eyebox). The eye box area refers to the area where the observer's eyes are located and can see the image displayed on the head-up display. For example, it can be a flat area or a three-dimensional area.

[0091] On the basis of the above-mentioned implementation manner, the embodiment of the present disclosure further provides a means of transportation, including: the above-mentioned head-up display system, which has corresponding beneficial effects. To avoid repeated description, it will not be repeated here.

[0092] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0093] The foregoing description is intended only to provide specific embodiments of the present disclosure, intended to enable those skilled in the art to understand and implement the present disclosure. Various modifications to these embodiments will be readily apparent to those 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 disclosure. Therefore, the present disclosure is not intended to be limited to the embodiments described herein, but rather to be construed in the broadest manner consistent with the principles and novel features disclosed herein.

Claims

1. An optical element, comprising a base lens; wherein: The base lens is a sheet lens, and a direction control unit and a diffusion unit are arranged on the base lens.

2. The optical element according to claim 1, wherein The direction control unit and the diffusion unit are both integrated on the base lens and are configured to adjust the angle of the incident light and diffuse it.

3. The optical element according to claim 1, wherein The direction control unit and the diffusion unit are configured as an integrated structural unit, the integrated structural unit includes a microlens array; and the microlens array is disposed on at least one side of the base lens.

4. The optical element according to claim 3, wherein: The microlens array is a cylindrical microlens array. Each cylindrical microlens in the cylindrical microlens array has a deflection angle to incident light. The deflection angle is determined by the focal length f and the eccentricity distance d of the cylindrical microlens.

5. The optical element according to claim 4, wherein: The cylindrical microlens array includes a first lens layer and a second lens layer, wherein the first lens layer and the second lens layer are arranged on the same side of the base lens; or, the first lens layer and the second lens layer are respectively arranged on two opposite sides of the base lens.

6. The optical element according to claim 5, wherein: The first lens layer comprises a plurality of first cylindrical lenses arranged continuously along a first direction, and light emitting surfaces of at least some of the first cylindrical lenses are eccentric arc surfaces; The second lens layer includes a plurality of second cylindrical lenses continuously arranged along a second direction, and light emitting surfaces of at least some of the second cylindrical lenses are eccentric arc surfaces, and an angle is formed between the second direction and the first direction.

7. The optical element according to claim 6, wherein: The first direction is perpendicular to the second direction.

8. The optical element according to claim 3, wherein: The microlens array is a spherical microlens array. Each spherical microlens in the spherical microlens array has a deflection angle to incident light, and the deflection angle is determined by the focal length f and the eccentric distance d of the spherical microlens.

9. The optical element according to claim 8, wherein: The spherical microlens array is arranged on one side surface of the base lens, and the light-emitting surfaces of at least some of the spherical microlenses in the spherical microlens array are eccentric arc surfaces.

10. The optical element according to claim 3, wherein: The aperture range of each microlens in the microlens array is greater than or equal to 500nm and less than or equal to 500um; When the microlens is a cylindrical microlens, the aperture is the width of the cylindrical lens; When the microlens is a spherical microlens, the aperture includes a radial dimension of the spherical microlens along a third direction or a radial dimension along a fourth direction, and the third direction is perpendicular to the fourth direction.

11. The optical element according to claim 3, wherein: The light emitting surface of each microlens in the microlens array is a convex surface or a concave surface.

12. The optical element according to claim 4 or 8, wherein: The range of the deflection angle is greater than or equal to -30 degrees and less than or equal to +30 degrees.

13. The optical element according to claim 1, wherein: The direction control unit and the diffusion unit are respectively arranged on two opposite sides of the base lens.

14. The optical element according to claim 13, wherein: The diffusion unit is configured as a diffusion microlens array or a Saier pattern, and the direction control unit is configured as a direction control lens array.

15. A head-up display system, comprising: An image source, the image source is used to emit image light, the image source comprises a backlight device, a light processing device and a display screen; wherein the light processing device comprises an optical element as claimed in any one of claims 1 to 14, the optical element is arranged in the light path between the backlight device and the display screen; A reflecting device is provided to reflect the image light to the eye box area to form a virtual image.

16. The head-up display system according to claim 15, wherein: The backlight device includes a backlight lamp board, which includes a mounting substrate, multiple backlights and a driving board. The backlights are mounted on the mounting substrate, and the driving board is electrically connected to the backlights. The driving board or the mounting substrate is provided with a wiring circuit, and the multiple backlights are respectively connected to the corresponding wiring circuits so that the brightness of at least some of the backlights can be independently controlled through the driving board.

17. A vehicle comprising the head-up display system according to claim 15 or 16.

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