A head-up display system

Abstract

The application provides a head-up display system, characterized by comprising a light source, a collimating element, a direction control element, a first diffusing element, a liquid crystal panel and a semi-transmissive and semi-reflective reflective imaging device; the direction control element, the first diffusing element and the liquid crystal panel are arranged on the same side of the light source in a stacked manner. The head-up display system provided by the embodiment of the application can converge most or all light rays of the light source in an aggregated and diffused manner in an observation range, so that the brightness during imaging can be improved, the light utilization rate is improved, the light source can ensure the imaging brightness under a lower power, so that the power consumption of the head-up display system can be reduced, and the heat emission amount is reduced. Even if a large-area liquid crystal panel needs to be arranged due to the need of large-size imaging, the power consumption increased is small, and the head-up display system is also suitable for large-area imaging.

Description

Technical Field

[0001] This invention relates to the field of optical imaging technology, and more specifically, to a head-up display system. Background Technology

[0002] Head-up display (HUD) technology uses the principle of optical reflection to project vehicle information such as speed onto the windshield or other glass. This can prevent drivers from looking down at the instrument panel while driving, thus improving driving safety and providing a better driving experience.

[0003] Most existing windshield-mounted head-up displays (HUDs) use liquid crystal displays (LCDs) as their image source. If a traditional LCD image source is used, the brightness of the image displayed on the windshield is relatively low. This is typically achieved by increasing the brightness of the LCD image source, which not only leads to higher power consumption but also generates more heat, increasing the requirements for heat dissipation. When a large image needs to be projected onto the windshield, the power consumption of the image source in the HUD will increase further. Summary of the Invention

[0004] To address the aforementioned problems, the purpose of this invention is to provide a head-up display system.

[0005] This invention provides a head-up display system, characterized in that it includes: a light source, a collimating element, a direction control element, a first diffusion element, a liquid crystal panel, and a semi-transparent and semi-reflective imaging device; the direction control element, the first diffusion element, and the liquid crystal panel are stacked on the same side of the light source.

[0006] The collimating element is used to adjust the emission direction of the light emitted by the light source to a preset angle range;

[0007] The direction control element is used to focus the light emitted by the light source to a preset position for viewing the image; the first diffusion element is used to diffuse the light emitted by the light source.

[0008] The liquid crystal panel is used to convert the light emitted by the light source into imaging light, and to incident the imaging light onto the reflective imaging device;

[0009] The reflective imaging device is used to reflect the imaging light to the preset position.

[0010] Optionally, in another embodiment, some or all of the collimating element is disposed between the light source and the direction control element;

[0011] The collimating element is used to emit the adjusted light to the direction control element.

[0012] Optionally, in another embodiment, the collimating element is used to adjust the light emitted by the light source into parallel light.

[0013] Optionally, in another embodiment, the collimating element includes a collimating lens and / or a collimating film, and the collimating lens and / or the collimating film is disposed between the light source and the direction control element;

[0014] The collimating lens includes one or more of the following: a convex lens, a concave lens, a Fresnel lens, or a combination of the above lenses.

[0015] Optionally, in another embodiment, when the collimating element includes a collimating lens, the distance between the collimating lens and the position of the light source is the focal length of the collimating lens.

[0016] Optionally, in another embodiment, the collimating element includes a hollow lamp cup;

[0017] The hollow lamp cup is a hollow shell including an inner reflective surface, and the opening of the hollow lamp cup faces the direction control element; the light source is disposed at the end of the hollow lamp cup away from the opening.

[0018] Optionally, in another embodiment, when the collimating element includes a collimating lens and / or a collimating film, the collimating lens and / or the collimating film are disposed inside the hollow lamp cup, and the size of the collimating lens and / or the collimating film is smaller than the opening size of the hollow lamp cup; the collimating lens and / or the collimating film are used to collimate a portion of the light emitted by the light source inside the hollow lamp cup before transmitting it to the direction control element.

[0019] Optionally, in another embodiment, the collimating element comprises a solid lamp cup;

[0020] The solid lamp cup is a solid transparent component with a refractive index greater than 1; the opening of the solid lamp cup faces the direction control element.

[0021] The light source is located at the end of the solid lamp cup away from the opening, and the light emitted by the light source undergoes total internal reflection when it hits the inner surface of the solid transparent component.

[0022] Optionally, in another embodiment, the solid lamp cup has a cavity at the end away from the opening of the solid lamp cup, and the side of the cavity near the opening of the solid lamp cup is convex; or

[0023] The solid lamp cup has a groove in the middle of the end near the opening of the solid lamp cup, and the bottom surface of the groove is convex.

[0024] Optionally, in another embodiment, the direction control element is disposed between the collimating element and the first dispersing element;

[0025] The direction control element is used to direct the focused light beam toward the first diffusion element.

[0026] Optionally, in another embodiment, the orientation control element includes one or more of a convex lens, a concave lens, a Fresnel lens, or a combination of the above lenses.

[0027] Optionally, in another embodiment, the distance between the orientation control element and the mirror position is the focal length of the orientation control element; the mirror position is the location of the virtual image formed by the reflection imaging device from the preset position.

[0028] Optionally, in another embodiment, the first diffusion element is disposed between the light source and the liquid crystal panel;

[0029] The first diffusion element is used to diffuse the light focused by the direction control element.

[0030] Optionally, in another embodiment, the head-up display system further includes a second diffusion element;

[0031] The first diffusion element and the second diffusion element are stacked, and there is a preset distance between the first diffusion element and the second diffusion element.

[0032] Optionally, in another embodiment, the first dispersing element and the second dispersing element are respectively disposed on both sides of the direction control element;

[0033] Alternatively, both the first diffusion element and the second diffusion element may be disposed on the side of the orientation control element near the liquid crystal panel.

[0034] Optionally, in another embodiment, the preset distance is 40-50 mm.

[0035] Optionally, in another embodiment, the diffusion element is a diffractive optical element or a scattering optical element.

[0036] Optionally, in another embodiment, the diffractive optical element diffuses the light passing through it to form one or more observation ranges with a preset cross-sectional shape, which is circular, elliptical, square, or rectangular.

[0037] Optionally, in another embodiment, the head-up display system further includes a polarization control element; the liquid crystal panel includes a first polarizer, a liquid crystal layer, and a second polarizer;

[0038] The first polarizer and the second polarizer are respectively disposed on both sides of the liquid crystal layer, and the first polarizer is disposed between the liquid crystal layer and the light source; the first polarizer is used to transmit first linearly polarized light, and the second polarizer is used to transmit second linearly polarized light perpendicular to the polarization direction of the first linearly polarized light.

[0039] The polarization control element is disposed between the light source and the first polarizer. The polarization control element is used to transmit the first linearly polarized light and reflect or absorb the second linearly polarized light.

[0040] Optionally, in another embodiment, the head-up display system further includes a light-blocking layer;

[0041] The light blocking layer is disposed on the side of the liquid crystal panel away from the light source, and the light blocking layer is used to limit the emission angle of the emitted light from the liquid crystal panel.

[0042] Optionally, in another embodiment, the head-up display system further includes a light-scattering layer;

[0043] The light scattering layer is disposed on the side of the light blocking layer away from the liquid crystal panel, and the light scattering layer is used to scatter ambient light.

[0044] In the above-described embodiment of the present invention, the direction control element and the first diffusion element respectively focus and diffuse the light, thereby effectively limiting the light emitted by the light source within the observation range. Within this range, the observer can normally view the image formed by the liquid crystal panel. Furthermore, by focusing and diffusing the light, most or all of the light from the light source can be concentrated within the observation range, thereby improving the brightness during imaging and increasing light utilization. This allows the light source to maintain imaging brightness even with lower power consumption, thus reducing the power consumption and heat generation of the head-up display system. Even if a large-area liquid crystal panel is required for large-size imaging, the increased power consumption is relatively small, meaning the head-up display system is also suitable for large-area imaging. Simultaneously, the collimation element collimates the light emitted by the light source, facilitating more effective focus and diffusion of the light by the direction control element and the first diffusion element, thus simplifying light control.

[0045] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0046] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0047] Figure 1 A first structural schematic diagram of the head-up display system provided in an embodiment of the present invention is shown;

[0048] Figure 2 A schematic diagram of the imaging principle of the head-up display system provided in an embodiment of the present invention is shown;

[0049] Figure 3a The present invention provides a schematic diagram of a diffusion element in the head-up display system.

[0050] Figure 3b The present invention provides a schematic diagram of another diffusion element in the head-up display system.

[0051] Figure 4 This diagram illustrates the imaging of a reflective imaging device in the head-up display system provided by an embodiment of the present invention.

[0052] Figure 5 A second structural schematic diagram of the head-up display system provided in an embodiment of the present invention is shown;

[0053] Figure 6 A third structural schematic diagram of the head-up display system provided in an embodiment of the present invention is shown;

[0054] Figure 7a This diagram illustrates a first arrangement of collimating elements provided in an embodiment of the present invention.

[0055] Figure 7b This diagram illustrates a second arrangement of collimating elements provided in an embodiment of the present invention.

[0056] Figure 8a A schematic diagram of the third arrangement of collimating elements provided in an embodiment of the present invention is shown;

[0057] Figure 8b A schematic diagram of the fourth arrangement of collimating elements provided in an embodiment of the present invention is shown;

[0058] Figure 9 A schematic diagram of the fifth arrangement of collimating elements provided in an embodiment of the present invention is shown;

[0059] Figure 10aA schematic diagram of the sixth arrangement of collimating elements provided in an embodiment of the present invention is shown;

[0060] Figure 10b A schematic diagram of the seventh arrangement of collimating elements provided in an embodiment of the present invention is shown;

[0061] Figure 11 This diagram illustrates a first structural schematic of the image source in the head-up display system provided by an embodiment of the present invention.

[0062] Figure 12 This diagram illustrates a second structure of the image source in the head-up display system provided by an embodiment of the present invention.

[0063] Figure 13 A schematic diagram of the third structure of the image source in the head-up display system provided in an embodiment of the present invention is shown;

[0064] Figure 14 This invention illustrates a schematic diagram of a lamp cup structure in a head-up display system provided by an embodiment of the present invention;

[0065] Figure 15a The diagram illustrates the light propagation of a frustum-shaped collimating element in the head-up display system provided in an embodiment of the present invention.

[0066] Figure 15b This invention provides a schematic diagram showing an arrangement of light sources within a frustum-shaped collimating element in a head-up display system.

[0067] Figure 15c This diagram illustrates another arrangement of the light source within the frustum-shaped collimating element in the head-up display system provided by an embodiment of the present invention.

[0068] Figure 15d This diagram illustrates another arrangement of the light source within the frustum-shaped collimating element in the head-up display system provided by an embodiment of the present invention.

[0069] Figure 16 This diagram illustrates the structure of the ridge-shaped lamp cup in the head-up display system provided by an embodiment of the present invention.

[0070] Figure 17 This shows a first structural schematic diagram of a solid lamp cup in the head-up display system provided by an embodiment of the present invention;

[0071] Figure 18 This shows a schematic diagram of the second structure of the solid lamp cup in the head-up display system provided in an embodiment of the present invention;

[0072] Figure 19 A schematic diagram of the fourth structure of the image source in the head-up display system provided in an embodiment of the present invention is shown;

[0073] Figure 20 A schematic diagram of the fifth structure of the image source in the head-up display system provided in an embodiment of the present invention is shown;

[0074] Figure 21 The diagram shows a sixth structural schematic of the image source in the head-up display system provided in an embodiment of the present invention.

[0075] icon:

[0076] 1-Image source, 10-Light source, 20-Collimating element, 21-Collimating lens, 22-Hollow lamp cup, 23-Solid lamp cup, 231-Reflective surface, 232-Cavity, 233-Convex surface, 234-Slotted, 235-Convex surface, 30-Direction control element, 41-First diffusion element, 42-Second diffusion element, 50-Liquid crystal panel, 51-First polarizer, 52-Liquid crystal layer, 53-Second polarizer, 60-Reflective imaging device, 70-Polarization control element, 80-Light blocking layer, 90-Light scattering layer, 100-Preset position, 101-Mirror position, 200-Observation range, 201-Mirror range, 300-Virtual image. Detailed Implementation

[0077] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0078] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0079] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0080] This invention provides a head-up display system that improves imaging brightness by controlling the light emission angle through light focusing and diffusion. See also... Figure 1 As shown, the head-up display system includes: a light source 10, a collimating element 20, a direction control element 30, a first diffusion element 41, a liquid crystal panel 50, and a transflective imaging device 60; as shown... Figure 1 As shown, the orientation control element 30, the first diffusion element 41, and the liquid crystal panel 50 are stacked on the same side of the light source 10.

[0081] In this embodiment of the invention, the light source 10 emits light, and the collimating element 20 is used to adjust the emission direction of the light emitted by the light source 10 to a preset angle range, thereby achieving collimation of the light emitted by the light source 10. The direction control element 30 is used to focus the light emitted by the light source 10 to a preset position 100 for viewing the image; the first diffusion element 41 is used to diffuse the light emitted by the light source 10. The liquid crystal panel 50 is used to convert the light emitted by the light source 10 into imaging light and incident the imaging light onto the reflective imaging device 60; the reflective imaging device 60 is used to reflect the imaging light back to the preset position 100, so that when the eyes of an observer (such as a driver, passenger, etc.) are located at the preset position 100, they can view the image formed by the liquid crystal panel 50. In this embodiment, the imaging light is the light emitted by the liquid crystal panel 50. The imaging light essentially comes from the light emitted by the light source 10. Each pixel of the liquid crystal panel 50 can control whether the light emitted by the light source 10 passes through it, so that when the observer sees the light passing through the liquid crystal panel 50 (i.e., the imaging light), they can see the image formed by the liquid crystal panel 50. The image formed by the liquid crystal panel 50 is the HUD image that can be viewed.

[0082] In this embodiment of the invention, since the light source 10 is generally a point light source, that is, the light emitted by the light source 10 is directed to various angles, this embodiment can adjust the emission direction of the light emitted by the light source 10 to a preset angle range by using the collimating element 20, thereby collimating the propagation direction of the light.

[0083] The direction control element 30 can focus the light emitted directly or indirectly from the light source 10 to a preset position 100. The light emitted directly from the light source 10 refers to the light emitted by the light source 10 that directly enters the direction control element 30, while the light emitted indirectly from the light source 10 refers to the light emitted by the light source that has passed through other components (such as the collimating element 20, the first diffusion element 41, etc.) before entering the direction control element 30. In this embodiment, by setting the direction control element 30, the light can be focused to the preset position 100; the focused light serves as the backlight of the liquid crystal panel 50, allowing it to be used for imaging. This enables an observer at the preset position 100 where the light is focused to observe a complete image, and because the light is focused, the image brightness is higher, allowing the observer to see a brighter image. Optionally, the collimating element 20 is used to adjust the light emitted by the light source 10 into parallel or nearly parallel light, so that the direction control element 30 can uniformly adjust the emission direction of the aligned parallel light. Optionally, the direction control element 30 includes one or more of the following: a convex lens, a concave lens, a Fresnel lens, or a combination of the above lenses. That is, the direction control element 30 can be a Fresnel lens, a convex lens, or a combination of lenses (such as a combination of a convex lens and a concave lens, or a combination of a Fresnel lens and a convex lens, etc.).

[0084] Meanwhile, in order to expand the imaging range and increase the area of ​​the image observed by the observer, in this embodiment of the invention, the light emitted by the light source 10 is diffused by the first diffusion element 41, thereby diffusing the light to a preset observation range 200. The first diffusion element 41 can diffuse the light emitted directly or indirectly by the light source 10. Here, the light emitted directly by the light source 10 refers to the light emitted by the light source 10 that directly incident on the first diffusion element 41, while the light emitted indirectly by the light source 10 refers to the light emitted by the light source that, after passing through other components (such as the collimating element 20, the direction control element 30, etc.), incident on the first diffusion element 41.

[0085] In this embodiment, the light emitted from the light source 10 is focused and diffused based on the direction control element 30 and the first diffusion element 41. The focused and diffused light serves as the backlight of the liquid crystal panel 50, enabling the liquid crystal panel 50 to form an image normally. The imaging light is reflected by the reflection imaging device 60 and reaches the preset position 100, allowing an observer with eyes at the preset position 100 to view the image formed by the liquid crystal panel 50. The image viewed by the observer is a virtual image 300 formed by the reflection imaging device 60 through reflection imaging. Simultaneously, under the action of the first diffusion element 41, the imaging light can be diffused into the observation range 200, allowing the observer to view the image formed by the liquid crystal panel 50 from any position within the observation range 200. The preset position 100 is a position within the observation range 200. Specifically, the observer can be a driver or a passenger. In this case, the area where the observer needs to view the image, i.e., the eyebox area, can be preset according to actual needs. The eyebox area refers to the area where the observer's eyes are located and can see the HUD image. At this point, it is sufficient that the observation range 200 described above can cover the eye box area, and the center of the eye box area can be set to the preset position 100. In this embodiment, the eye box area has a certain size. Even if the observer's eyes deviate from the center of the eye box area by a certain distance, such as moving a certain distance up or down or left or right, as long as the observer's eyes are still within the eye box area, the observer can still see the HUD image.

[0086] For details on the working principle of this head-up display system, please refer to [link / reference]. Figure 2 As shown, for ease of explanation, Figure 2 The following explanation uses a planar reflective imaging device 60 as an example. Figure 2 As shown, the collimating element 20 collimates the light emitted from the light source 10. Figure 2 Taking the collimated light as a parallel light source as an example, this parallel light, after passing through the direction control element 30 and the first blurring element 41, can be adjusted to the light source required for imaging. Figure 2Taking the leftmost ray A' as an example, after passing through the direction control element 30, ray A' is adjusted to face the preset position 100. However, due to the presence of the reflection imaging device 60, ray A actually faces the mirror image position 101 of the preset position 100. If the first diffusion element 41 is not present, ray A can travel along the light path a, be reflected by the reflection imaging device 60, and then be directed towards the preset position 100. When the first diffusion element 41 is present, it diffuses ray A into multiple rays with different exit angles (such as rays A1 and A2 in Figure 2). The diffused rays can be dispersed into a range, namely the observation range 200, after being reflected by the reflection imaging device 60. This allows the observer to see the image of the liquid crystal panel 50 when their eye is within the observation range 200. Similarly, the diffused rays A1, A2, etc., directly face the mirror image range 201 of the observation range 200. Furthermore, in practical applications, the reflection imaging device 60 can have a certain curvature, and its imaging principle is similar to... Figure 2 Similar to the example shown, it will not be described again here. Those skilled in the art should understand that, for a curved reflective imaging device 60 such as a windshield, the position of the virtual image 300 is not fixed when viewed from different positions. Therefore, when the reflective imaging device 60 is a curved windshield or imaging window, the virtual image 300 in this embodiment refers to the virtual image 300 that can be seen when viewed from the preset position 100, that is, the position of the virtual image 300 is the position of the virtual image when the observer views it from the preset position 100.

[0087] Specifically, the first diffusing element 41 can be a low-cost scattering optical element, such as a homogenizer or diffuser. Alternatively, the first diffusing element 41 can also be a diffractive optical element (DOE) with better control over the diffusion effect, such as a beam shaper. In this case, when light passes through a homogenizer or other scattering optical element, scattering occurs, and the light is transmitted to many different angles, and a small amount of diffraction also occurs, but scattering plays a major role, resulting in a relatively large light spot. In contrast, a diffractive optical element, by designing specific microstructures on its surface, mainly achieves beam expansion through diffraction, resulting in a smaller light spot, and the size and shape of the light spot are controllable.

[0088] In this embodiment, the light beam transformed after passing through the first diffusing element 41 has a specific shape in its cross-section perpendicular to the propagation direction of the principal optical axis. That is, the first diffusing element 41 can diffract the light passing through it to form an observation range 200 of a specific shape. The size and shape of the observation range 200 formed by diffraction are mainly determined by the microstructure of the first diffusing element 41. Optionally, the shape of the observation range 200 includes, but is not limited to, a circle, an ellipse, a square, or a rectangle, such as... Figure 3aAs described above, after the light passes through the first diffusing element 41, which is specifically a diffractive optical element, the light diffuses and forms a specific cross-sectional shape, which corresponds to the shape of the observation range 200. Figure 3a Taking the observation range of 200 as a rectangle as an example, the above... Figure 2 The example used is a rectangle with an observation range of 200.

[0089] Furthermore, the first dispersing element 41 can also be a discrete dispersing element, meaning that the first dispersing element 41 can disperse the light passing through it into multiple ranges, each range having a shape including but not limited to a circle, ellipse, square, or rectangle. Figure 3b As shown, after passing through the separate first diffusion element 41, the light can be diffused into multiple regions, each region corresponding to an observation range 200; Figure 3b The example of light scattering into two rectangular areas is used to illustrate this.

[0090] Optionally, to better achieve the focusing effect, the preset position 100 corresponds to the focal point of the direction control element 30. In this embodiment, the distance between the direction control element 30 and the mirror position 101 is the focal length of the direction control element 30; wherein, the mirror position 101 is the location of the virtual image formed by the reflection imaging device 60 from the preset position 100, as detailed in [reference needed]. Figure 4 As shown.

[0091] In this embodiment of the invention, in addition to the reflective imaging device 60, the light source 10, collimating element 20, direction control element 30, first diffusion element 41, liquid crystal panel 50, etc., can constitute the image source 1 of the head-up display system, that is, the image source 1 includes the light source 10, collimating element 20, direction control element 30, first diffusion element 41, and liquid crystal panel 50, etc. Figure 4 As shown, the imaging light emitted from image source 1 (which is also the imaging light emitted from liquid crystal panel 50) is reflected by the reflective imaging device 60 and reaches the preset position 100, allowing an observer with their eye at the preset position 100 to see the virtual image 300 formed by the reflective imaging device 60. Simultaneously, for an object at the preset position 100, a virtual image of that object can also be formed on the other side of the reflective imaging device 60; the location of this virtual image is the mirror position 101. Furthermore, since the reflective imaging device 60 is not necessarily planar, the "distance between the direction control element 30 and the mirror position 101" in this embodiment specifically refers to the optical path length of light rays incident from the direction control element 30 to the mirror position 101.

[0092] Specifically, the head-up display system is installed on vehicles or other means of transportation. In this embodiment, the reflective imaging device 60 can be the vehicle's windshield or a film applied to the windshield. The reflective imaging device 60 has a semi-transparent, semi-reflective characteristic, allowing the imaging light emitted from the liquid crystal panel 50 to be reflected by the reflective imaging device 60 to a preset position 100. Simultaneously, light from outside the vehicle can also pass through the reflective imaging device 60 and reach the preset position 100, allowing an observer at the preset position 100 to normally view the scene outside the vehicle. In this embodiment, "semi-transparent, semi-reflective" means that the reflective imaging device 60 can both transmit and reflect light, and is not limited to transmitting 50% and reflecting 50%.

[0093] Optionally, when the head-up display system is installed on vehicles or other means of transportation, a separate first diffusion element 41 can be used. This first diffusion element 41 disperses the light emitted by the light source 10 into multiple viewing areas 200. Specifically, the first diffusion element 41 disperses the light emitted by the light source 10 into two viewing areas 200, corresponding to the driver and front passenger respectively. This allows both the driver and front passenger to view the image formed by the liquid crystal panel 50, while minimizing light loss and maximizing light utilization.

[0094] This invention provides a head-up display system in which a direction control element 30 and a first diffusion element 41 focus and diffuse light, respectively, effectively confining the light emitted by the light source 10 within an observation range 200. Within this range, the observer can normally view the image formed by the reflection of the liquid crystal panel 50 by the reflective imaging device 60. Furthermore, by focusing and diffusing the light, most or all of the light from the light source 10 can be concentrated within the observation range 200, thereby improving the brightness during imaging and increasing light utilization. This allows the light source 10 to maintain imaging brightness even at lower power, thus reducing the power consumption and heat generation of the head-up display system. Even if a large-area liquid crystal panel 50 is required for large-size imaging, the increased power consumption is relatively small, meaning this head-up display system is also suitable for large-area imaging. Simultaneously, the collimation element 20 collimates the light emitted by the light source 10, facilitating more effective focus and diffusion of the light by the direction control element 30 and the first diffusion element 41, thus simplifying light control.

[0095] Based on the above embodiments, the direction control element 30, the first diffusion element 41, and the liquid crystal panel 50 can be arranged in various stacking configurations. For example... Figure 1As shown, a direction control element 30, a first diffusion element 41, and a liquid crystal panel 50 are sequentially stacked along the emission direction of the light from the light source 10. This allows the light from the light source 10 to be first focused and then diffused, ultimately serving as backlight for imaging. Alternatively, as... Figure 5 As shown, a first directional diffusing element 41, a control element 30, and a liquid crystal panel 50 are sequentially stacked along the emission direction of the light from the light source 10. This allows the light from the light source 10 to be first diffused and then focused, ultimately serving as backlight for imaging. Alternatively, as... Figure 6 As shown, the direction control element 30, the liquid crystal panel 50, and the first diffusion element 41 are stacked sequentially along the emission direction of the light from the light source 10. That is, the light from the light source 10 is first focused, then directly used as backlight for imaging, and finally the imaging light is diffused. Other stacking methods can be used, which will not be described in detail here.

[0096] To facilitate light control, a method of first focusing and then diffusing light is generally adopted. Specifically, the light source 10 and the first diffusing element 41 are respectively positioned on opposite sides of the direction control element 30. The first diffusing element 41 is used to diffuse the light focused by the direction control element 30. For details, please refer to [reference needed]. Figure 1 or Figure 6 As shown. Furthermore, to reduce the impact on imaging of the liquid crystal panel 50, the first diffusion element 41 is disposed between the light source 10 and the liquid crystal panel 50, as shown. Figure 1 As shown. Simultaneously, the collimating element 20 can first collimate the light beam, followed by focusing and diffusing it; that is, the direction control element 30 and the first diffusing element 41 are also located on the same side of the collimating element 20. In this embodiment, the direction control element 30 is located between the collimating element 20 and the first diffusing element 41; the direction control element 30 is used to focus the collimated light beam and emit the focused light beam to the first diffusing element 41.

[0097] Based on the above embodiments, the head-up display system can be provided with multiple collimating elements 20, each collimating element 20 containing one or more light sources 10. The multiple light sources 10 can be arranged in a matrix as a light source dot matrix, such as four light sources 10 arranged in a 2×2 dot matrix; or, the multiple light sources 10 can be arranged in a linear array, such as four light sources 10 arranged in a 1×4 array. The collimating elements 20 can collimate the light emitted by the light sources 10 within them; simultaneously, the multiple collimating elements 20 can be arranged in a closely packed manner to avoid some areas failing to form backlight. Specifically, as shown... Figure 7a and Figure 7b As shown, the collimating element 20 is circular in shape, and multiple collimating elements 20 are closely stacked. In this embodiment, the "shape of the collimating element" refers to the outer contour shape of the cross-section of the collimating element 20. Figure 1 This is a side view of the head-up display system. Figure 7a and Figure 7b This is a schematic diagram showing the arrangement of the collimating elements 20 when viewed from above.

[0098] Since the light source 10 is generally a point light source, using a circular collimating element 20 can utilize the light emitted by the light source 10 most efficiently, improving light utilization. However, when the circular collimating elements 20 are arranged closely, there will inevitably be gaps between the two collimating elements 20, thus reducing space utilization. To balance light utilization and space utilization, the collimating elements 20 can be arranged in a completely compact stacking manner. In this embodiment, "completely compact stacking" means that after compact stacking, there may be no gaps between the collimating elements 20. When the shape of the collimating elements 20 is quadrilateral (such as rhombus, rectangle, etc.) or hexagonal (preferably regular hexagonal), a completely compact stacking arrangement can be achieved. See also Figure 8a and Figure 8b As shown, the collimating element 20 is rectangular in shape, and multiple collimating elements 20 are arranged in a completely close-packed manner; the figure shows two completely close-packed arrangements of the rectangular collimating elements 20. Alternatively, see [link to other documentation]. Figure 9 As shown, the collimating element 20 has a regular hexagonal shape, and multiple collimating elements 20 are arranged in a completely compact stack.

[0099] While the hexagonal arrangement improves space utilization, it also slightly reduces light utilization. Optionally, the collimating element 20 is octagonal (preferably a regular octagon), and multiple collimating elements 20 are closely stacked. Furthermore, since octagons cannot achieve completely close stacking, small light sources can be used to fill the gaps. Specifically, such as... Figure 10a and Figure 10b As shown, sub-collimating elements of matching size are additionally arranged in the gaps between the multiple collimating elements 20. These sub-collimating elements can be of any shape; the figure illustrates this by using an octagonal sub-collimating element as an example. Since an octagon is closer to a circle than a hexagon, it has higher light utilization and also higher space utilization compared to a circular array.

[0100] Based on the above embodiments, although the collimating element 20 can collimate the light emitted by the light source 10, perfect collimation cannot be achieved in practice, resulting in relatively weak brightness at the edges of the collimating element 20. In particular, when multiple collimating elements 20 are arranged in a close-packed manner, darker areas are easily formed in the gaps between the collimating elements 20. In this embodiment, multiple diffusion elements are spaced apart to uniformly distribute the light brightness. Figure 11 As shown, the head-up display system also includes a second diffusion element 42; the first diffusion element 41 and the second diffusion element 42 are stacked and arranged with a preset distance between them.

[0101] In this embodiment of the invention, both the first diffusing element 41 and the second diffusing element 42 can diffract the light emitted by the light source 10. Simultaneously, the first diffusing element 41 and the second diffusing element 42 can uniformly diffract the light after it has been collimated by the collimating element 20, resulting in relatively uniform imaging brightness of the liquid crystal panel 50. Essentially, both the first diffusing element 41 and the second diffusing element 42 are diffusing elements, specifically diffractive optical elements (DOEs), such as beam shapers. The size and shape of the observation range 200 formed by diffraction are determined by the microstructure of the beam shaper. Alternatively, the diffusing element can be a scattering optical element, such as a light homogenizer or a diffuser. The specific structure of the diffusing element can be found in the description of the first diffusing element 41 above, and will not be repeated here.

[0102] In this embodiment, the head-up display system uses multiple spaced-apart diffusion elements (including the first diffusion element 41 and the second diffusion element 42) to diffuse light while also uniformly dispersing the light brightness, thus ensuring uniform imaging brightness of the liquid crystal panel 50.

[0103] Meanwhile, to ensure that all multiple dispersing elements can function effectively, adjacent dispersing elements are spaced by a preset distance, specifically 40-50 mm. Furthermore, in this embodiment, the multiple dispersing elements can all be positioned on the same side of the direction control element 30, such as... Figure 11 As shown, both the first diffusion element 41 and the second diffusion element 42 are disposed on the side of the orientation control element 30 closest to the liquid crystal panel 50. Alternatively, when the thickness of the orientation control element 30 is not greater than the preset distance, the diffusion elements can be distributed on both sides of the orientation control element 30 to reduce the overall thickness of the image source 1; specifically as follows... Figure 12 As shown, the first diffusion element 41 and the second diffusion element 42 are respectively disposed on both sides of the direction control element 30.

[0104] Based on the above embodiments, in order to improve the focusing and diffusing effect of the direction control element 30 and the first diffusing element 41 on the light, the light emitted by the light source 10 is first collimated in this embodiment, that is, the light source 10 and the collimating element 20 are set on the same side of the direction control element 30 (or the first diffusing element 41); at the same time, part or all of the collimating element 20 is set between the light source 10 and the direction control element 30; the collimating element 20 is used to emit the adjusted light to the direction control element 30.

[0105] In this embodiment, the collimating element 20 may include a collimating lens 21 and / or a collimating film, and the collimating lens 21 and / or the collimating film are disposed between the light source 10 and the direction control element 30. The collimating lens 21 may be one or more of a convex lens, a concave lens, a Fresnel lens, or a combination of these lenses (e.g., a combination of a convex lens and a concave lens, a combination of a Fresnel lens and a concave lens, etc.). The collimating film may be a brightness enhancement film (BEF) used to adjust the outgoing direction of light to a preset angle range, for example, focusing the light within an angle range of ±35° of the collimating film normal. Furthermore, the light source 10 can be positioned at the focal point of the collimating lens 21, i.e., the distance between the collimating lens 21 and the light source 10 is the focal length of the collimating lens 21, so that light rays emitted from the light source 10 in different directions can be emitted in parallel after passing through the collimating lens 21. See [link to details]. Figure 13 As shown.

[0106] In this embodiment, if the collimating element 20 only includes the collimating lens 21 and / or the collimating film, then the entire collimating element 20 can be located between the light source 10 and the direction control element 30. Alternatively, the collimating element 20 adjusts the emission direction of the light from the light source 10 by reflection; specifically, the collimating element 20 has a reflective surface capable of reflecting the light emitted by the light source 10. By setting the curvature of the reflective surface, the reflection angle of the light can be adjusted, thereby constraining the emission direction of the light emitted by the light source 10 within a preset angle range, or even adjusting the light from the light source 10 to parallel light. The reflective surface can be implemented using a lamp cup structure, specifically the inner reflective surface of a hollow lamp cup.

[0107] like Figure 13 As shown, the collimating element 20 includes a hollow lamp cup 22. The hollow lamp cup 22 is a hollow shell including an inner reflective surface, and the opening of the hollow lamp cup 22 faces the direction control element 30. The light source 10 is disposed at the end of the hollow lamp cup 22 away from the opening, and the emission direction of the light from the light source 10 is adjusted using the inner reflective surface of the hollow lamp cup 22. The inner reflective surface of the hollow lamp cup 22 can be parabolic, freeform, equilateral triangular pyramid, isosceles triangular pyramid, or cubic pyramid, etc.

[0108] Meanwhile, to more comprehensively collimate the light emitted from the light source 10, the collimating element 20 may have a reflective surface, and may also have a collimating lens 21 and / or a collimating film. The collimating lens 21 and / or the collimating film are disposed inside the hollow lamp cup 22, and the size of the collimating lens 21 and / or the collimating film is smaller than the opening size of the hollow lamp cup; the collimating lens 21 and / or the collimating film are used to collimate a portion of the light emitted from the light source 10 inside the hollow lamp cup 22 before transmitting it to the direction control element 30. Figure 13As shown, the collimating lens 21 of the collimating element 20 collimates part of the light emitted from the light source 10 (i.e., Figure 13 The light rays (indicated by the thick arrow) are collimated, and the exit angle of this part of the light rays is relatively small; while the light rays emitted by the light source 10 have a larger exit angle (i.e., Figure 13 The light rays (indicated by the thin arrow) are collimated through the inner reflective surface of the hollow lamp cup 22, thus combining the collimating lens 21 and the hollow lamp cup 22 to more effectively collimate the light rays emitted by the light source 10.

[0109] Optionally, the collimating lens 21 and / or collimating film can completely cover the opening of the hollow lamp cup 22; in this case, the hollow lamp cup 22 mainly functions as a reflector, and the collimating lens 21 and / or collimating film mainly functions as a collimator. A schematic diagram of one structure of the collimating element 20 can be found... Figure 14 As shown, the light emitted by light source 10 has a relatively large exit angle (similar to...). Figure 13 The light rays (indicated by the thin arrows in the image) will have their emission direction change after passing through the collimating lens 21 again after being collimated by the hollow lamp cup. However, due to the characteristics of the light source 10 (e.g., the light source 10 is an LED lamp), most of the energy of the light emitted by the light source 10 is concentrated in a fan-shaped area, such as... Figure 13 The area indicated by the medium-thick arrow, representing most (e.g., about 80%) of the light emitted from light source 10, is collimated by collimating lens 21. Based on Figure 14 The collimating element 20 shown can also perform the collimation function, and the manufacturing process of the collimating element 20 is simple and convenient. At the same time, when there are multiple collimating elements 20, the collimating lens 21 of each collimating element 20 can be cut, for example, into an equilateral triangle, a regular hexagon, or a regular square, so that the collimating elements 20 can be closely arranged.

[0110] Optionally, due to the large number of collimating elements 20, to simplify the manufacturing process, the collimating elements 20 in this embodiment can be hollow shells with an inner reflective surface in the shape of a frustum, that is, the collimating element 20 is frustum-shaped, and the cross-sectional shape or opening shape of the collimating element 20 is quadrilateral, specifically, it can be a parallelogram, rectangle, square, or trapezoid. The collimating element 20 has a gradually increasing opening, and this opening is the light outlet of the collimating element 20. For example... Figure 15a and Figure 15b As shown, the light source 10 is positioned at the bottom end of the opening of the collimating element 20 (e.g., Figure 15a (On the left side of the collimating element 20), the light emitted by the light source 10 is reflected by the reflective surface inside the collimating element 20 and then exits through the opening (e.g., on the left side of the collimating element 20). Figure 15a The light is emitted from the right side of the collimating element 20. Furthermore, as described above, multiple light sources 10 can also be provided within the collimating element 20. For example... Figure 15cAs shown, multiple light sources 10 can be arranged in a matrix to form a light source dot matrix. Figure 15c Six light sources are arranged in a 2×3 dot matrix; or, as... Figure 15d As shown, multiple light sources 10 can also be arranged in a linear array. Figure 15d There are three light sources arranged in a central line.

[0111] Optional, see Figure 16 As shown, the collimating element 20 is a ridge-shaped lamp cup with an opening, and the light sources 10 are arranged in a row at the ends of the ridge-shaped lamp cup away from the opening; the light emitted by the row of light sources 10 can be uniformly emitted along the opening direction through the ridge-shaped lamp cup, thereby providing uniform light to the image source 1.

[0112] Alternatively, in this embodiment of the invention, the collimating element 20 may include a solid lamp cup 23; the solid lamp cup 23 is a solid transparent component with a refractive index greater than 1; the opening of the solid lamp cup 23 faces the direction control element 30; the light source 10 is disposed at the end of the solid lamp cup 23 away from the opening, and the light emitted by the light source 10 undergoes total internal reflection when it strikes the inner surface of the solid transparent component.

[0113] In this embodiment, the solid lamp holder 23 is a solid transparent component, and the opening direction of the solid lamp holder 23 refers to the opening direction of the reflective surface 231 of the solid lamp holder 23. See also Figure 17 As shown, the reflective surface 231 of the solid lamp cup 23 is the inner surface of the solid transparent component. The solid transparent component has a cavity 232 at the end away from the opening for placing the light source 10. That is, the light source 10 is set at the bottom of the lamp cup away from the opening of the solid lamp cup. When the light emitted by the light source 10 hits the reflective surface 231 of the solid lamp cup 23, since the refractive index of the solid lamp cup 23 is greater than 1, and the outer medium of the solid lamp cup 23 is air (refractive index 1), when the light emitted by the light source 10 reaches the reflective surface 231 of the solid lamp cup 23, the light travels from the optically denser medium (i.e., the solid lamp cup 23) to the optically less dense medium (i.e., the air surrounding the solid lamp cup 23). As long as the incident angle of the light emitted by the light source 10 hits the reflective surface 231 reaches the preset angle, total internal reflection can occur. By setting the surface shape of the reflective surface 231 of the solid lamp cup, the light emitted obliquely by the light source 10 can be collimated. Specifically, the reflective surface 231 of the solid lamp cup can be a free-form surface (i.e., it cannot be represented by a simple surface function mathematically) or a composite parabola (i.e., the reflective surface is composed of multiple parabolic segments), both of which can better collimate the light emitted by the light source 10.

[0114] Simultaneously, the collimating lens 21 can be integrated onto the solid lamp reflector 23 to further improve the collimation effect. See also Figure 17As shown, the solid transparent component has a cavity 232 at the end away from the opening of the solid lamp holder, and the side of the cavity 232 near the opening of the solid lamp holder is a convex surface 233. Alternatively, as... Figure 18 As shown, the solid transparent component has a slot 234 at the middle position of the end near the opening of the solid lamp cup, and the bottom surface of the slot 234 is a convex surface 235. Figure 17 or Figure 18 The solid lamp cup 23 shown can be directly used as a collimation element 20.

[0115] In this embodiment, the convex surface 233 of the cavity 232 or the convex surface 235 of the slot 234 are both used to collimate the light emitted by the light source 10, that is, the convex surface 233 or convex surface 235 is equivalent to the collimating lens 21. The convex surface 233 or convex surface 235 is located in the middle of the solid transparent component, and the size of the convex surface 233 or convex surface 235 is smaller than the opening size of the solid lamp cup 23; the convex surface 233 or convex surface 235 is used to collimate a portion of the light emitted by the light source 10 inside the solid lamp cup 23 before transmitting it to the direction control element 30. Figure 17 As shown, the convex surface 233 is placed inside the cavity at the tail end of the solid lamp cup. This convex surface 233 forms a convex lens, collimating the light rays incident on it. Alternatively, see... Figure 18 As shown, a slot 234 is provided in the middle of the solid transparent component, and the bottom surface of the slot 234 is a convex surface 235. The convex surface 235 of the solid lamp cup is used to collimate the light that cannot be reflected by the reflective surface 231 of the solid lamp cup. Other light rays with larger exit angles undergo total internal reflection within the solid lamp cup 23 before being collimated and emitted from the solid lamp cup 23. The solid lamp cup 23 is made of a transparent material with a refractive index greater than 1, such as a transparent polymer material or glass.

[0116] Optionally, the collimating lens 21 and / or collimating film can completely cover the opening of the solid lamp cup 23; in this case, the solid lamp cup 23 mainly functions as a reflector, and the collimating lens 21 and / or collimating film mainly functions as a collimator. The structure of the collimating element 20 in this case can be found in [reference needed]. Figure 14 As shown, its working principle is the same as the relevant content described above, and will not be repeated here.

[0117] Based on the above embodiments, when the first diffusion element 41 is a separate diffusion element and the collimating element 20 is a solid lamp cup 23 with good collimation effect, the collimated light, after passing through the first diffusion element 41, diffuses and disperses to multiple ranges, that is, the light is directly dispersed to multiple areas, each area corresponding to an observation range 200. In this embodiment, the separate first diffusion element 41, in addition to diffusing the light, can also separate the light to different observation ranges 200. The process of separating the light to different observation ranges 200 is similar to the function of the direction control element 30 in controlling the direction of the light. Both can control the direction of the light, that is, the diffusion element can also play a role in direction control and can emit light to the observation ranges 200 corresponding to different directions.

[0118] Based on the above embodiments, see Figure 19 As shown, the head-up display system also includes a polarization control element 70; the liquid crystal panel 50 includes a first polarizer 51, a liquid crystal layer 52, and a second polarizer 53.

[0119] The first polarizer 51 and the second polarizer 53 are respectively disposed on both sides of the liquid crystal layer 52, and the first polarizer 51 is disposed between the liquid crystal layer 52 and the light source 10. The first polarizer 51 is used to transmit the first linearly polarized light, and the second polarizer 53 is used to transmit the second linearly polarized light perpendicular to the polarization direction of the first linearly polarized light. The polarization control element 70 is disposed between the light source 10 and the first polarizer 51. The polarization control element 70 is used to transmit the first linearly polarized light and reflect or absorb the second linearly polarized light.

[0120] In this embodiment of the invention, polarizers with perpendicular polarization states are respectively provided on the upper and lower sides of the liquid crystal layer 52 of the liquid crystal panel 50, namely a first polarizer 51 and a second polarizer 53. First linearly polarized light can pass through the first polarizer 51, and second linearly polarized light can pass through the second polarizer 52, with the polarization direction of the first linearly polarized light perpendicular to that of the second linearly polarized light. Since the light emitted by the light source 10 is generally unpolarized, approximately 50% of the light energy is absorbed by the first polarizer 51 between the liquid crystal layer and the light source 10. Since the polarizer is generally attached to the surface of the liquid crystal layer 52, this portion of the light energy causes the first polarizer 51 and the liquid crystal layer 52 to heat up, affecting the lifespan of the liquid crystal panel 50.

[0121] In this embodiment of the invention, a polarization control element 70 is disposed between the light source 10 and the first polarizer 51. This polarization control element 70 can transmit first linearly polarized light and reflect or absorb second linearly polarized light, ensuring that only first linearly polarized light reaches the first polarizer 51. This prevents the first polarizer 51 from absorbing second linearly polarized light, avoids heat absorption by the liquid crystal panel 50, and thus extends the lifespan of the liquid crystal panel 50. The second linearly polarized light emitted by the light source 10 can be absorbed by the polarization control element 70, provided that the polarization control element 70 is spaced a certain distance from the liquid crystal panel 50. Furthermore, if the polarization control element 70 can reflect the second linearly polarized light, the reflected second linearly polarized light can be reflected again by other components (such as the reflective surface of the collimating element 20) and returned to the polarization control element 70. A portion of this light can be converted into first linearly polarized light, allowing more light to be used for imaging on the liquid crystal panel 50, thereby improving light utilization.

[0122] Optionally, the polarization control element 70 is a reflective polarization reflective film, specifically a DBEF (Dual Brightness Enhancement Film), a BEF, a photonic crystal with selective polarization and incident angle transmittance, etc., and when the polarization control element 70 can reflect second linearly polarized light, the polarization control element 70 can be attached to the outer surface of the liquid crystal panel 50.

[0123] Based on the above embodiments, see Figure 20 As shown, the head-up display system also includes a light blocking layer 80; the light blocking layer 80 is disposed on the side of the liquid crystal panel 50 away from the light source 10, and the light blocking layer 80 is used to limit the emission angle of the emitted light from the liquid crystal panel 50.

[0124] In this embodiment of the invention, the light-blocking layer 80 includes a plurality of light-blocking fences with preset heights. These raised light-blocking fences form a fence array to physically block the propagation of light in certain directions. By designing the height and width of the light-blocking fences, the angle at which an observer can see the light can be limited. Figure 20 As shown, the light is confined within the viewing angle α by the light blocking layer 80, thus forming an observable area; that is, the human eye eye-1 is located within the observable area, and can see the light emitted by the light source 10. However, the human eye eye-2 is located outside the observable area, so the human eye eye-2 cannot see the light emitted by the light source 10, and therefore the human eye eye-2 cannot observe the image of the liquid crystal panel 50.

[0125] In this embodiment, the light-blocking layer 80 can be a fence array, which can be horizontal, vertical, or at any angle, so that only light parallel to the fence can pass through. The viewing angle of the light-blocking layer 80 can be 48 degrees, 60 degrees, 75 degrees, or any other desired angle. Furthermore, the light-blocking layer 80 can be two fence arrays stacked orthogonally, or two fence arrays stacked at a certain angle. Each fence array layer can be horizontal, vertical, or at any angle. The viewing angle can be 48 degrees, 60 degrees, 75 degrees, or any other desired angle. Specifically, the light-blocking layer 80 can be a privacy shutter.

[0126] In this embodiment of the invention, a light-blocking layer 80 is added to the outer surface of the liquid crystal panel 50 to limit the angle of light emission and achieve certain specific purposes. For example, if an image source 1 without the light-blocking layer 80 is placed on the surface of the vehicle's control panel, the driver may simultaneously see the image on the liquid crystal panel 50 and the image reflected from the windshield, affecting the driver's driving. The light-blocking layer 80, however, ensures that light is emitted only towards the windshield, preventing the driver from seeing the image on the liquid crystal panel 50 itself, thus avoiding the image on the liquid crystal panel 50 from affecting driving.

[0127] Optional, see Figure 21 As shown, the head-up display system also includes a light-scattering layer 90; the light-scattering layer 90 is disposed on the side of the light-blocking layer 80 away from the liquid crystal panel 50, and is used to scatter ambient light. In this embodiment of the invention, a light-scattering layer 90 is disposed on the outside of the light-blocking layer 80, which can scatter ambient light, such as sunlight, thereby preventing glare caused by sunlight shining on the surface of the light-blocking layer 80. Specifically, the light-scattering layer 90 and the light-blocking layer 80 can be integrally formed, such as a frosted privacy shutter.

[0128] Furthermore, it should be noted that in all the embodiments described above, a distance is placed between each component for ease of describing the structure of the head-up display system, or for ease of describing the propagation or direction of light. For example... Figure 1There is a gap between the light control element 30 and the first diffusion element 41, but this is not intended to limit the existence of a gap between them. That is, the light control element 30 and the first diffusion element 41 can be placed close together, or the gap between them can be very small. The same applies to the arrangement of other adjacent elements, unless specifically stated that a certain distance is required between the two elements, such as the gap between the first diffusion element 41 and the second diffusion element 42 mentioned above. Furthermore, the accompanying drawings in the above embodiments are merely schematic structural diagrams, illustrating only the dimensions of each element, and do not represent actual size proportions.

[0129] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A head-up display system, characterized in that, include: Light source, collimating element, direction control element, first diffusion element, liquid crystal panel and semi-transparent and semi-reflective imaging device; The direction control element, the first diffusion element, and the liquid crystal panel are stacked on the same side of the light source; The collimating element is used to adjust the emission direction of the light emitted by the light source to a preset angle range; When the directional control element is used in a non-reflective imaging device, it focuses the principal optical axis light emitted by the light source to a mirror position of a preset position for viewing the image. The mirror position is the position of the virtual image formed by the preset position through the reflective imaging device. The distance between the directional control element and the mirror position is the focal length of the directional control element. The first diffusion element is used to diffuse the light emitted by the light source into the observation range; the preset position is located within the observation range, and the area of ​​the preset position is smaller than the area of ​​the observation range; The liquid crystal panel is used to convert the light emitted by the light source into imaging light, and to incident the imaging light onto the reflective imaging device; The reflective imaging device is used to reflect the imaging light to the preset position.

2. The head-up display system according to claim 1, characterized in that, Some or all of the collimation element is disposed between the light source and the direction control element; The collimating element is used to emit the adjusted light to the direction control element.

3. The head-up display system according to claim 1, characterized in that, The collimating element is used to adjust the light emitted by the light source into parallel light.

4. The head-up display system according to claim 1, characterized in that, The collimating element includes a collimating lens and / or a collimating film, and the collimating lens and / or the collimating film is disposed between the light source and the direction control element; The collimating lens includes one or more of the following: a convex lens, a concave lens, a Fresnel lens, or a combination of the above lenses.

5. The head-up display system according to claim 4, characterized in that, When the collimating element includes a collimating lens, the distance between the collimating lens and the position of the light source is the focal length of the collimating lens.

6. The head-up display system according to any one of claims 1-5, characterized in that, The collimation element includes a hollow lamp cup; The hollow lamp cup is a hollow shell including an inner reflective surface, and the opening of the hollow lamp cup faces the direction control element; the light source is disposed at the end of the hollow lamp cup away from the opening.

7. The head-up display system according to claim 6, characterized in that, When the collimating element includes a collimating lens and / or a collimating film, the collimating lens and / or the collimating film are disposed inside the hollow lamp cup, and the size of the collimating lens and / or the collimating film is smaller than the opening size of the hollow lamp cup; the collimating lens and / or the collimating film are used to collimate a portion of the light emitted by the light source inside the hollow lamp cup and then emit it to the direction control element.

8. The head-up display system according to any one of claims 1-5, characterized in that, The collimation element includes a solid lamp cup; The solid lamp cup is a solid transparent component with a refractive index greater than 1; the opening of the solid lamp cup faces the direction control element. The light source is located at the end of the solid lamp cup away from the opening, and the light emitted by the light source undergoes total internal reflection when it hits the inner surface of the solid transparent component.

9. The head-up display system according to claim 8, characterized in that, The solid lamp cup has a cavity at the end away from the opening of the solid lamp cup, and the side of the cavity near the opening of the solid lamp cup is convex; or The solid lamp cup has a groove in the middle of the end near the opening of the solid lamp cup, and the bottom surface of the groove is convex.

10. The head-up display system according to claim 1, characterized in that, The direction control element is disposed between the collimation element and the first diffusion element; The direction control element is used to direct the focused light beam toward the first diffusion element.

11. The head-up display system according to claim 10, characterized in that, The orientation control element includes one or more of the following: a convex lens, a concave lens, a Fresnel lens, or a combination of the above lenses.

12. The head-up display system according to claim 1, characterized in that, The first diffusion element is disposed between the light source and the liquid crystal panel; The first diffusion element is used to diffuse the light focused by the direction control element.

13. The head-up display system according to claim 12, characterized in that, It also includes a second diffusion element; The first diffusion element and the second diffusion element are stacked, and there is a preset distance between the first diffusion element and the second diffusion element.

14. The head-up display system according to claim 13, characterized in that, The first diffusion element and the second diffusion element are respectively disposed on both sides of the direction control element; Alternatively, both the first diffusion element and the second diffusion element may be disposed on the side of the orientation control element near the liquid crystal panel.

15. The head-up display system according to claim 13, characterized in that, The preset distance is 40-50mm.

16. The head-up display system according to any one of claims 1, 12-15, characterized in that, The diffusion element is a diffractive optical element or a scattering optical element.

17. The head-up display system according to claim 16, characterized in that, The diffractive optical element diffuses the light passing through it to form one or more observation ranges with a preset cross-sectional shape, which is a circle, ellipse, square or rectangle.

18. The head-up display system according to claim 1, characterized in that, It also includes a polarization control element; the liquid crystal panel includes a first polarizer, a liquid crystal layer, and a second polarizer. The first polarizer and the second polarizer are respectively disposed on both sides of the liquid crystal layer, and the first polarizer is disposed between the liquid crystal layer and the light source; the first polarizer is used to transmit first linearly polarized light, and the second polarizer is used to transmit second linearly polarized light perpendicular to the polarization direction of the first linearly polarized light. The polarization control element is disposed between the light source and the first polarizer. The polarization control element is used to transmit the first linearly polarized light and reflect or absorb the second linearly polarized light.

19. The head-up display system according to claim 1, characterized in that, Also includes: Light-blocking layer; The light blocking layer is disposed on the side of the liquid crystal panel away from the light source, and the light blocking layer is used to limit the emission angle of the emitted light from the liquid crystal panel.

20. The head-up display system according to claim 19, characterized in that, It also includes a light-scattering layer; The light scattering layer is disposed on the side of the light blocking layer away from the liquid crystal panel, and the light scattering layer is used to scatter ambient light.

Images