Display device

Abstract

The invention provides a display device and a display terminal, the display device comprises a display module and a reflection diffusion structure, and the display module is used for emitting display light; the reflection and diffusion structure is arranged on a light emitting path of the vehicle-mounted display module and is used for reflecting the display light and reflecting the display light to the target imaging structure; the reflection and diffusion structure comprises a cholesteric liquid crystal layer, the cholesteric liquid crystal layer is used for controlling the light emitting angle or focal power of reflected light rays, the cholesteric liquid crystal layer can optimize the diffusion mode of the reflected light rays by adjusting the inclination angle of a spiral shaft of liquid crystal molecules, it is ensured that the light rays are evenly distributed on an imaging area of a windshield, and the imaging effect is improved. Therefore, stray light is effectively reduced, unnecessary light is prevented from entering the visual field of a driver, and the visual effect is improved.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a display device. Background Art

[0002] Head-Up Display (HUD) technology projects light from an image source (including key information such as vehicle speed) onto the car's windshield or other imaging windows, allowing drivers to directly obtain the information they need while driving without having to look down at the dashboard. As drivers' demand for information interaction experience continues to increase, the market prospects for head-up displays are gradually expanding.

[0003] Currently, the industry usually adopts the method of increasing the size of the picture generation unit (PGU) and using free-form surface mirrors to expand the field of view (FOV) to improve the display effect; however, increasing the size of the device requires a stronger light source to maintain the display brightness, resulting in a significant increase in power consumption; secondly, larger mirrors increase system complexity, making it difficult to ensure image uniformity, and imaging problems such as distortion or blur may occur; in addition, increasing the mirror area is also prone to introducing stray light, further interfering with the display effect and reducing the driver's visual experience. Summary of the invention

[0004] The embodiments of the present application provide a display device to alleviate the deficiencies in the related art.

[0005] To achieve the above functions, the technical solutions provided by the embodiments of the present application are as follows:

[0006] An embodiment of the present application provides a display device, including:

[0007] A display module, used for emitting display light;

[0008] A dimming structure, arranged on a light-emitting path of the display module, the dimming structure is used to receive the display light and reflect the display light onto a target imaging structure;

[0009] Wherein, the dimming structure comprises a cholesteric liquid crystal layer, and the cholesteric liquid crystal layer is used to control the light output angle or optical focal length of the reflected light.

[0010] In one embodiment, the cholesteric liquid crystal layer includes a first cholesteric liquid crystal sublayer, a second cholesteric liquid crystal sublayer and a third cholesteric liquid crystal sublayer which are stacked, the first cholesteric liquid crystal sublayer reflects a first color light, the second cholesteric liquid crystal sublayer reflects a second color light, and the third cholesteric liquid crystal sublayer reflects a third color light; wherein the first color, the second color and the third color are different colors.

[0011] In one embodiment, the wavelength of the third color light is shorter than the wavelength of the second color light, and the wavelength of the second color light is shorter than the wavelength of the first color light;

[0012] The thickness of the third cholesteric liquid crystal sublayer is greater than the thickness of the second cholesteric liquid crystal sublayer, and the thickness of the second cholesteric liquid crystal sublayer is greater than the thickness of the first cholesteric liquid crystal sublayer.

[0013] In one embodiment, the dimming structure includes a first alignment layer, the first alignment layer is arranged on one side of the cholesteric liquid crystal layer, the first alignment layer includes a plurality of first alignment portions, and the plurality of first alignment portions are sequentially arranged in a direction away from the center of the first alignment layer;

[0014] The pretilt angle of the first alignment portion far from the center of the alignment layer is different from the pretilt angle of the first alignment portion close to the center of the alignment layer.

[0015] In one embodiment, the cholesteric liquid crystal layer includes a plurality of cholesteric liquid crystal molecules;

[0016] The helical axis tilt angle of the cholesteric liquid crystal molecules far from the center of the cholesteric liquid crystal layer is greater than the helical axis tilt angle of the cholesteric liquid crystal molecules close to the center of the cholesteric liquid crystal layer.

[0017] In one embodiment, the dimming structure includes a diffusion film, and the diffusion film is disposed on a side of the cholesteric liquid crystal layer close to the display module, and the diffusion film covers the cholesteric liquid crystal layer.

[0018] In one embodiment, the size of the diffusion film in the first direction is greater than the size of the diffusion film in the second direction, the diffusion film has a first diffusion angle in the first direction, and the diffusion film has a second diffusion angle in the second direction;

[0019] The first diffusion angle is greater than or equal to 5 degrees and less than or equal to 25 degrees, and the second diffusion angle is greater than or equal to 5 degrees and less than or equal to 15 degrees.

[0020] In one embodiment, the dimming structure includes a first alignment layer, and the first alignment layer is arranged on a side of the cholesteric liquid crystal layer away from the diffusion film;

[0021] The diffusion film includes a liquid crystal layer, the liquid crystal layer includes a plurality of liquid crystal molecules, and an orthographic projection of the liquid crystal layer on the first alignment layer is located in the first alignment layer.

[0022] In one embodiment, the dimming structure includes a first substrate and a second substrate disposed opposite to each other, the cholesteric liquid crystal layer is disposed between the first substrate and the second substrate, the cholesteric liquid crystal layer includes a plurality of cholesteric liquid crystal molecules, and the long axes of the cholesteric liquid crystal molecules are disposed parallel to the horizontal plane where the first substrate is located;

[0023] In the third direction, the arrangement of the plurality of cholesteric liquid crystal molecules changes periodically in a first direction perpendicular to the third direction; wherein the third direction is a direction perpendicular to the cholesteric liquid crystal layer, and the first direction is arranged perpendicular to the third direction.

[0024] In one embodiment, the second substrate includes a central axis extending along a first direction;

[0025] In one period, the angle between the long axis and the central axis of the cholesteric liquid crystal molecules far from the center of the cholesteric liquid crystal layer is greater than the angle between the long axis and the central axis of the cholesteric liquid crystal molecules close to the center of the cholesteric liquid crystal layer.

[0026] The beneficial effects of the embodiments of the present application are as follows: the embodiments of the present application provide a display device and a display terminal, wherein the display device includes a display module and a reflective diffusion structure, wherein the display module is used to emit display light; the reflective diffusion structure is arranged on the light output path of the vehicle-mounted display module, so as to reflect the display light and form a virtual image on the imaging area of ​​the windshield where the reflected light is emitted; wherein the reflective diffusion structure includes a cholesteric liquid crystal layer, wherein the cholesteric liquid crystal layer is used to control the light output angle or optical focal length of the reflected light, and the cholesteric liquid crystal layer can optimize the diffusion mode of the reflected light by adjusting the inclination angle of the helical axis of the liquid crystal molecules, thereby ensuring that the light is evenly distributed on the windshield and improving the uniformity of imaging, thereby effectively reducing the generation of stray light and avoiding unnecessary light from entering the driver's field of view, thereby improving the visual effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0028] Figure 1 A schematic diagram of a first structure of a display device provided in an embodiment of the present application;

[0029] Figure 2 A schematic diagram of the first structure of the dimming structure provided in the embodiment of the present application;

[0030] Figure 3 A schematic diagram of the first structure of the diffusion membrane provided in the embodiment of the present application;

[0031] Figure 4 A schematic diagram of the first structure of the reflective layer provided in an embodiment of the present application;

[0032] Figure 5 A schematic diagram of the structure of the first alignment layer provided in an embodiment of the present application;

[0033] Figure 6 A second structural schematic diagram of the dimming structure provided in an embodiment of the present application;

[0034] Figure 7 A reflection spectrum curve diagram of the imaging structure provided in the embodiment of the present application;

[0035] Figure 8 A second structural schematic diagram of the display device provided in an embodiment of the present application;

[0036] Fig. 9 A top view of the dimming structure provided in an embodiment of the present application;

[0037] Fig.10 This is a schematic diagram of the third structure of the dimming structure provided in the embodiment of the present application. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present application. In addition, it should be understood that.

[0039] The specific embodiments described herein are only used to illustrate and explain the present application and are not used to limit the present application. In the present application, unless otherwise stated, the directional words used, such as "upper" and "lower", generally refer to the upper and lower parts of the device in actual use or working mode, specifically the drawing direction in the accompanying drawings; while "inside" and "outside" refer to the outline of the device. In addition, the terms "first" and "second" are only used for descriptive purposes, and the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present application, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0040] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection; it can be a mechanical connection, an electrical connection, or can communicate with each other; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0041] The disclosure below provides many different embodiments to realize the different structures of the present application. In order to simplify the disclosure of the present application, the parts and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the present application. In addition, the various specific processes and material examples provided by the present application, but those of ordinary skill in the art can appreciate the application of other processes and / or the use of other materials.

[0042] The present application provides a display device. The following are detailed descriptions. It should be noted that the description order of the following embodiments is not intended to limit the preferred order of the embodiments.

[0043] Please combine Figure 1 and Figure 2 ;in, Figure 1 A schematic diagram of a first structure of a display device provided in an embodiment of the present application; Figure 2 This is a schematic diagram of the first structure of the dimming structure provided in the embodiment of the present application; wherein: Figure 1 The complete optical path diagram of the display light emitted from the display device and reflected to the imaging structure is shown. The diagram details how the light emitted from the display device is guided by the dimming structure and finally the display content is projected onto the imaging structure.

[0044] In one embodiment, the display device 1 may be a head-up display device 1, which projects the light (including key information such as vehicle speed) emitted by the display module 11 (image source) onto the imaging area of ​​the windshield of the car (imaging structure 13) or other imaging windows. After the light is reflected on the surface of the imaging structure 13, a virtual image is formed, so that the driver can directly obtain the required information without having to lower his head to check the dashboard during driving. It should be noted that this embodiment does not impose specific restrictions on the imaging area, which can be located at any appropriate position of the windshield or on other transparent windows to achieve the effect of information projection, thereby improving the convenience and safety of driving.

[0045] The display device 1 includes a display module 11 and a dimming structure 12, wherein the display module 11 is used to emit display light L1; the dimming structure 12 is arranged on the light output path of the display module 11, and the dimming structure 12 is used to receive the display light L1 and reflect the display light L1 onto a target imaging structure 13; wherein the dimming structure 12 includes a cholesteric liquid crystal layer 1211, and the cholesteric liquid crystal layer 1211 is used to control the light output angle of the reflected light.

[0046] It can be understood that cholesteric liquid crystal is a liquid crystal material with chiral properties, and its liquid crystal molecules are arranged in a spiral shape in space. This spiral arrangement characteristic enables the cholesteric liquid crystal to selectively reflect light of a certain wavelength that matches its spiral period, thereby forming a color or optical effect; in this embodiment, the dimming structure 12 is set on the light output path of the display module 11, and the dimming structure 12 includes a cholesteric liquid crystal layer 1211. The cholesteric liquid crystal layer 1211 is used to control the light output angle of the reflected light, thereby reducing stray light in the reflection process, allowing the driver to see a clearer image on the imaging structure 13, thereby improving the visual experience and safety.

[0047] Please combine Figure 1 , Figure 2 and Figure 3 ;in, Figure 3 This is a schematic diagram of the first structure of the diffusion membrane provided in an embodiment of the present application.

[0048] In one embodiment, the dimming structure 12 includes a reflective layer 121 and a diffusion film 122. The reflective layer 121 can accurately reflect the display light L1 to form a reflected light L2. The reflective layer 121 includes the cholesteric liquid crystal layer 1211. The diffusion film 122 is arranged on a side of the reflective layer 121 close to the display module 11, and the diffusion film 122 covers the cholesteric liquid crystal layer 1211.

[0049] The diffusion film 122 can scatter the display light L1 directed toward the reflective layer 121 to a certain extent, so that the display light L1 is more evenly distributed after passing through the diffusion film 122, which helps to improve the uniformity and visual comfort of the display light L1, so that more light can be effectively projected onto the imaging structure 13, reducing light loss and further improving the driver's visual effect.

[0050] It can be understood that, in this embodiment, the reflective layer 121 includes a cholesteric liquid crystal layer 1211, and the cholesteric liquid crystal layer 1211 can effectively reflect the display light L1, optimize the propagation path of the display light L1, and thus improve the imaging quality; at the same time, by arranging the diffusion film 122 to cooperate with the cholesteric liquid crystal layer 1211 box, the dimming structure 12 can optimize the display light L1, reduce the loss of the reflected light L2, and achieve the expansion of the field of view, thereby improving the visual effect of the driver.

[0051] Specifically, the diffusion film 122 is arranged on a side of the reflective layer 121 close to the display module 11, and the diffusion film 122 covers the cholesteric liquid crystal layer 1211. The diffusion film 122 can preliminarily scatter and homogenize the display light L1 emitted to the cholesteric liquid crystal layer 1211, thereby ensuring that the distribution of the display light L1 is more uniform; and after passing through the diffusion film 122, the display light L1 will enter the cholesteric liquid crystal layer 1211 at an appropriate angle, so that it can better utilize the arrangement characteristics of the liquid crystal molecules in the cholesteric liquid crystal layer 1211, thereby enhancing the focusing ability and reflection effect of the display light L1.

[0052] Please combine Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 ;in, Figure 4 A schematic diagram of the first structure of the reflective layer provided in an embodiment of the present application; Figure 5 This is a schematic diagram of the structure of the first alignment layer provided in an embodiment of the present application.

[0053] In one embodiment, the reflective layer 121 includes a first orientation layer 1212, which is arranged on one side of the cholesteric liquid crystal layer 1211, and the first orientation layer 1212 includes a plurality of first orientation portions 12121, which are arranged in sequence in a direction away from the center of the first orientation layer 1212; wherein the pretilt angle of the first orientation portion 12121 away from the center of the orientation layer is different from the pretilt angle of the first orientation portion 12121 close to the center of the orientation layer, so that the arrangement of the cholesteric liquid crystal molecules 12111 in the cholesteric liquid crystal layer 1211 can be adjusted by controlling the pretilt angle, thereby providing greater design flexibility.

[0054] The cholesteric liquid crystal layer 1211 includes a plurality of cholesteric liquid crystal molecules 12111, and each of the first orientation portions 12121 corresponds to a plurality of cholesteric liquid crystal molecules 12111. Since each of the first orientation portions 12121 has a different pretilt angle, the corresponding plurality of cholesteric liquid crystal molecules 12111 can exhibit different orientation characteristics under the influence of different anchoring forces. It can be understood that, in this embodiment, the anchoring force of the first orientation portion 12121 can be designed so that the cholesteric liquid crystal molecules 12111 can better maintain the desired arrangement state, thereby reducing the influence of external interference (such as temperature changes and electric field fluctuations) on its orientation, thereby improving the performance of the display device 1 and ensuring that clear images can be provided under different usage conditions.

[0055] It should be noted that the reflective layer 121 also includes a second orientation layer 1213, the first orientation layer 1212 and the second orientation layer 1213 are arranged opposite to each other, and the cholesteric liquid crystal layer 1211 is arranged between the first orientation layer 1212 and the second orientation layer 1213; wherein, the structure of the second orientation layer 1213 is the same as that of the first orientation layer 1212, and the structure of the first orientation layer 1212 has been described in detail in the above embodiment, and therefore, the structure of the second orientation layer 1213 will not be repeated in this embodiment.

[0056] Please continue to combine Figures 1 to 5 In one embodiment, the helical axis inclination angle of the cholesteric liquid crystal molecules 12111 away from the center of the cholesteric liquid crystal layer 1211 is greater than the helical axis inclination angle of the cholesteric liquid crystal molecules 12111 close to the center of the cholesteric liquid crystal layer 1211, thereby making the helical axis inclination angles of the plurality of cholesteric liquid crystal molecules 12111 gradually increase in the direction away from the center of the cholesteric liquid crystal layer 1211.

[0057] It should be noted that, in this embodiment, the helical axis inclination angle refers to the angle formed by the cholesteric liquid crystal molecules 12111 in their helical structure relative to the normal direction of the first orientation layer 1212, which directly affects the light regulation ability and optical properties of the cholesteric liquid crystal molecules 12111.

[0058] It can be understood that, in this embodiment, a gradual optical refractive index gradient is formed in the cholesteric liquid crystal layer 1211 by setting the helical axis inclination angle of the cholesteric liquid crystal molecules 12111 away from the center of the cholesteric liquid crystal layer 1211 to be greater than the helical axis inclination angle of the cholesteric liquid crystal molecules 12111 close to the center of the cholesteric liquid crystal layer 1211. Specifically, when light propagates in the cholesteric liquid crystal layer 1211, due to the larger helical axis inclination angle of the cholesteric liquid crystal molecules 12111 away from the center of the cholesteric liquid crystal layer 1211, the cholesteric liquid crystal molecules 12111 at that position will guide the light to be deflected inward (similar to the edge focusing of a lens effect), so that the light gradually converges toward the center area of ​​the layer, thereby increasing the light intensity in this area; at the same time, the scattering and loss of light are reduced, thereby improving the overall light effect of the display.

[0059] Furthermore, the helical axis inclination angle of the cholesteric liquid crystal molecules 12111 is greater than or equal to 0 degrees and less than or equal to 10 degrees. The smaller inclination angle of the cholesteric liquid crystal molecules 12111 helps to maintain the orderly arrangement and stability of the cholesteric liquid crystal molecules 12111 and avoid light scattering and distortion problems that may be caused by excessive helical axis inclination angle of the cholesteric liquid crystal molecules 12111.

[0060] Please continue to combine Figures 1 to 5 In one embodiment, the size of the diffusion film 122 in the first direction X is greater than the size of the diffusion film 122 in the second direction Y, the diffusion film 122 has a first diffusion angle in the first direction X, and the diffusion film 122 has a second diffusion angle in the second direction Y, and the first diffusion angle is different from the second diffusion angle.

[0061] It can be understood that this embodiment can effectively adjust the light intensity and distribution characteristics in different directions by controlling the diffusion angle of the diffusion film 122 in the first direction X and the diffusion angle in the second direction Y, thereby reducing visual discomfort caused by excessive light concentration or divergence.

[0062] The diffusion film 122 may be rectangular, and the size of the diffusion film 122 in the first direction X may be the length of the long side of the diffusion film 122, and the size of the diffusion film 122 in the second direction Y may be the length of the short side of the diffusion film 122. Different diffusion effects may be achieved by adjusting the size and diffusion angle of the diffusion film 122 in different directions.

[0063] Specifically, the rectangularly designed diffusion film 122 can have different optical properties in two directions. By optimizing the size and diffusion angle of the diffusion film 122 in different directions, a wider light distribution can be achieved in a specific direction, thereby improving the user experience. For example, the long side direction can be designed so that the display light L1 diffuses more widely in that direction, while the short side direction is relatively concentrated, allowing more accurate light control and a smaller diffusion angle. In actual applications, the diffusion film 122 enables the display light L1 emitted from the display module 11 to propagate at a wider angle in one direction, thereby enhancing the field of view, so that the driver can obtain clear information within a larger angle range without being limited to a specific viewing angle.

[0064] Furthermore, the first diffusion angle is greater than or equal to 5 degrees and less than or equal to 25 degrees, and the second diffusion angle is greater than or equal to 5 degrees and less than or equal to 15 degrees. By reasonably designing the first diffusion angle and the second diffusion angle, the display light L1 can maintain a higher image clarity after passing through the diffusion film 122, reducing the blurring phenomenon caused by excessive light scattering.

[0065] Combination Figures 1 to 5 It can be understood that when the display module 11 emits display light L1 (for example, vehicle speed, navigation information, etc.), the display light L1 will first pass through the diffusion film 122. The diffusion film 122 causes the display light L1 to undergo multiple tiny scatterings within the film, which helps to evenly disperse the concentrated emitted display light L1, thereby achieving the effect of diffusing the display light L1, and further reducing the unevenness of the light, so that the display light L1 emitted from the display module 11 presents uniform brightness as a whole.

[0066] When the display light L1 diffused by the diffusion film 122 enters the reflective layer 121, the arrangement of the cholesteric liquid crystal molecules 12111 in the reflective layer 121 can change the propagation characteristics of the display light L1, and can make the display light L1 converge in a specific direction during the reflection process, thereby forming a clear virtual image; wherein, the arrangement of the cholesteric liquid crystal molecules 12111 is affected by the pretilt angle of the first orientation layer 1212, and by adjusting the pretilt angle of the first orientation layer 1212, the orientation arrangement of the cholesteric liquid crystal molecules 12111 can be changed, thereby affecting the propagation characteristics of the display light L1.

[0067] When the display light L1 after being reflected by the cholesteric liquid crystal layer 1211, that is, the reflected light L2, enters the diffusion film 122 again, the diffusion film 122 diffuses the reflected light L2 to ensure the uniformity and comfort of the reflected light L2 before it is emitted, and ensures that the reflected light L2 finally emitted to the imaging structure 13 covers a wider range, thereby improving the field of view of the display device 1.

[0068] It should be noted that the present embodiment does not impose any specific limitation on the structure of the cholesteric liquid crystal layer 1211. The cholesteric liquid crystal layer 1211 can reflect light of any color, and in practical applications, the helical axis inclination angle design of the cholesteric liquid crystal layer 1211 can be flexibly adjusted according to the specific optical requirements of the display device 1, and the present embodiment does not impose any specific limitation on this.

[0069] In one embodiment, the first orientation layer 1212 is arranged on a side of the cholesteric liquid crystal layer 1211 away from the diffusion film 122; the diffusion film 122 includes a liquid crystal layer, and the liquid crystal layer includes a plurality of liquid crystal molecules. The orthographic projection of the liquid crystal layer on the first orientation layer 1212 is located in the first orientation layer 1212, so that by arranging liquid crystal molecules in the diffusion film 122, it is ensured that the liquid crystal molecules are uniformly arranged under the action of the anchoring force of the first orientation layer 1212, thereby achieving a diffusion effect on the display light L1.

[0070] Specifically, the diffusion film 122 can be a liquid crystal diffusion film 122, and the liquid crystal diffusion film 122 can be directly formed on the cholesteric liquid crystal layer 1211 by spin coating liquid crystal molecules, thereby eliminating or reducing the interface between the liquid crystal diffusion film 122 and the cholesteric liquid crystal layer 1211, and can significantly reduce the scattering of light at the interface, so that more display light L1 will be effectively guided and reflected to the target area, thereby improving the utilization efficiency of light.

[0071] It can be understood that, in this embodiment, the orthographic projection of the liquid crystal layer on the first orientation layer 1212 is arranged to be located within the first orientation layer 1212. The liquid crystal molecules in the diffusion film 122 can better maintain their arrangement state under the anchoring force of the first orientation layer 1212, thereby achieving effective light diffusion; at the same time, the structure of the overall display device 1 is simplified, making the manufacturing process more efficient, which helps to reduce production costs.

[0072] Please continue to combine Figure 1 , Figure 3 , Figure 5 , Figure 6 and Figure 7 ;in, Figure 6 A second structural schematic diagram of the dimming structure provided in an embodiment of the present application; Figure 7This is a reflection spectrum curve diagram of the imaging structure provided in the embodiment of the present application.

[0073] In one embodiment, the cholesteric liquid crystal layer 1211 includes a first cholesteric liquid crystal sublayer 121A, a second cholesteric liquid crystal sublayer 121B and a third cholesteric liquid crystal sublayer 121C which are stacked, wherein the first cholesteric liquid crystal sublayer 121A reflects a first color light, the second cholesteric liquid crystal sublayer 121B reflects a second color light, and the third cholesteric liquid crystal sublayer 121C reflects a third color light; wherein the first color, the second color and the third color are different colors, so that the reflective layer 121 can reflect multiple colors, thereby improving the color gamut of the display device 1, enabling it to display more colors, and thereby enhancing the user's visual experience.

[0074] Specifically, the first cholesteric liquid crystal sublayer 121A includes a plurality of first cholesteric liquid crystal molecules 12111, and the first cholesteric liquid crystal molecules 12111 are used to reflect a first color light. The second cholesteric liquid crystal sublayer 121B includes a plurality of second cholesteric liquid crystal molecules 12111, and the second cholesteric liquid crystal molecules 12111 are used to reflect a second color light. The third cholesteric liquid crystal sublayer 121C includes a plurality of third cholesteric liquid crystal molecules 12111, and the third cholesteric liquid crystal molecules 12111 are used to reflect a third color light.

[0075] Among them, the wavelength of the third color light is smaller than the wavelength of the second color light, the wavelength of the second color light is smaller than the wavelength of the first color light, the first color light can be red light, the wavelength range of the first color light is 635nm to 700nm, the second color light can be green light, the wavelength range of the second color light is 495nm to 570nm, the third color light can be blue light, the wavelength range of the third color light is 450nm to 490nm, so that the reflection wide wavelength range of the cholesteric liquid crystal layer 1211 is 450nm to 700nm, that is, the reflected light of the cholesteric liquid crystal layer 1211 covers a wide visible spectrum range of light.

[0076] Furthermore, the imaging structure 13 may be a windshield of a car. Fig. 9 The displayed reflection intensity curve shows that light of different wavelengths has different reflection degrees when passing through the imaging structure 13; among them, the reflectivity of blue light (450nm to 490nm) is lower, while the reflectivity of red light (635nm to 700nm) is higher.

[0077] According to the reflection intensity formula of the cholesteric liquid crystal layer 1211: R = tanh 2(KL); wherein R is the reflection intensity, K is a constant related to the refractive index, reflecting the propagation characteristics of light in the liquid crystal layer, and L is the thickness of the liquid crystal layer. It can be seen that when the K value remains unchanged, the thickness L of the liquid crystal layer directly determines the reflection intensity, that is, by adjusting the thickness of the liquid crystal layer, the reflection ability of light of a specific wavelength can be accurately controlled; in this embodiment, since the imaging structure 13 has a low reflectivity for blue light, a thicker reflective layer 121 (liquid crystal layer that reflects blue light) is required to increase the blue light reflection intensity, thereby ensuring that sufficient blue light is reflected.

[0078] Specifically, the thickness of the third cholesteric liquid crystal layer 121C is greater than the thickness of the second cholesteric liquid crystal layer 121B, and the thickness of the second cholesteric liquid crystal layer 121B is greater than the thickness of the first cholesteric liquid crystal layer 121A, thereby increasing the reflection intensity of the cholesteric liquid crystal layer 1211 for blue light. That is, this embodiment can effectively complement the reflection spectrum of the imaging structure 13 by designing cholesteric liquid crystal layers with different thicknesses, so that the reflection layer 121 can more effectively adjust the distribution of light when reflecting light of different colors, thereby achieving the purpose of optimizing the visual effect.

[0079] Please continue to combine Figure 8 , Fig. 9 and Fig.10 ;in, Figure 8 A second structural schematic diagram of the display device provided in an embodiment of the present application; Fig. 9 A top view of the dimming structure provided in an embodiment of the present application;

[0080] Fig.10 This is a schematic diagram of the third structure of the dimming structure provided in the embodiment of the present application; wherein, Figure 8 The complete optical path diagram of the display light emitted from the display device and reflected to the imaging structure is shown. The diagram details how the light emitted from the display device is guided by the dimming structure and finally the display content is projected onto the imaging structure.

[0081] It should be noted that as drivers' demand for information interaction experience continues to increase, the market prospects for head-up displays are gradually expanding; however, current head-up display devices can usually only provide a field of view of about 10 degrees. This limitation reduces the amount of information that the head-up display device can present, thereby affecting the user's usage effect and overall experience.

[0082] In one embodiment, the display device 1 includes a display module 11 and a dimming structure 12, wherein the display module 11 is used to emit a display light L1; the dimming structure 12 is arranged on the light output path of the display module 11, and the dimming structure 12 is used to receive the display light L1 and reflect the display light L1 onto a target imaging structure 13; wherein the dimming structure 12 includes a cholesteric liquid crystal layer 1211, and the cholesteric liquid crystal layer 1211 is used to control the optical focal length of the reflected light.

[0083] It can be understood that optical focal length is a measure of the ability of an optical system or component to focus light, and is usually used to measure how light will focus on a certain focal point or area after passing through a specific material or component. In this embodiment, the dimming structure 12 is arranged on the light output path of the display module 11. The dimming structure 12 includes a cholesteric liquid crystal layer 1211. The cholesteric liquid crystal layer 1211 is used to control the optical focal length of the reflected light. By adjusting the optical focal length, the focusing or divergence of the reflected light can be controlled, thereby adjusting the viewing angle range, making the reflected light more concentrated or dispersed, and optimizing the user's viewing experience.

[0084] Further, the dimming structure 12 includes a first substrate 123 and a second substrate 124 that are arranged opposite to each other, the cholesteric liquid crystal layer 1211 is arranged between the first substrate 123 and the second substrate 124, the cholesteric liquid crystal layer 1211 includes a plurality of cholesteric liquid crystal molecules 12111, and the long axes of the cholesteric liquid crystal molecules 12111 are arranged parallel to the horizontal plane where the first substrate 123 is located; in a third direction Z, the arrangement of the plurality of cholesteric liquid crystal molecules 12111 changes periodically in a first direction X that is perpendicular to the third direction Z; wherein the third direction Z is a direction perpendicular to the cholesteric liquid crystal layer 1211, the first direction X is arranged perpendicular to the third direction Z, and the third direction can be Fig.10 The first direction X may be Fig. 9 X direction.

[0085] It can be understood that, in this embodiment, by arranging the long axis of the cholesteric liquid crystal molecule 12111 in parallel with the horizontal plane where the first substrate 123 is located, the scattering characteristics of the display light L1 can be better controlled to improve the display effect; specifically, the arrangement of the plurality of cholesteric liquid crystal molecules 12111 changes periodically in the first direction X perpendicular to the third direction Z, that is, the cholesteric liquid crystal molecules 12111 are repeatedly arranged in a certain direction and period. Since in the cholesteric liquid crystal layer 1211, the plurality of cholesteric liquid crystal molecules 12111 are in a spiral structure, the spiral structure arrangement of the cholesteric liquid crystal molecules 12111 enables it to reflect light of a specific wavelength and scatter other light at the same time. This scattering effect helps to evenly distribute the light and improve the display effect.

[0086] That is, the cholesteric liquid crystal layer 1211 can control the propagation path of light by changing the period and spiral direction of the molecular arrangement, thereby regulating the characteristics of the light (such as direction and focusing degree). For example, when light needs to be concentrated, the cholesteric liquid crystal layer 1211 can make the light gather in a certain direction, achieving a similar "focusing" effect; when light needs to be evenly dispersed, the cholesteric liquid crystal layer 1211 can achieve "scattering".

[0087] At the same time, the cholesteric liquid crystal layer 1211 is designed to achieve the light scattering effect without introducing an additional diffusion film 122 , thereby reducing the number of components and manufacturing process steps, helping to reduce costs and improve the reliability of the display device 1 .

[0088] It should be noted that PB phase regulation (Pancharatnam-Berry phase modulation) controls the phase change of light by the arrangement of liquid crystal molecules. The liquid crystal molecules themselves have birefringence, and the liquid crystal molecules will change the propagation path of light according to the polarization state; specifically, when the liquid crystal molecules are arranged in a specific way and have a certain deflection angle, the polarization state of the incident light will change accordingly. Since the propagation speed of light in the birefringent medium is different, its polarization state change will cause a new phase to be added to the light wavefront, that is, by adjusting the liquid crystal molecules, the phase distribution of the wavefront after reflection of the light can be changed.

[0089] Furthermore, in the present embodiment, the second substrate 124 includes a central axis W1 extending along the first direction Z; within one period, the angle between the long axis of the cholesteric liquid crystal molecule 12111 away from the center of the cholesteric liquid crystal layer 1211 and the central axis W1 is greater than the angle between the long axis of the cholesteric liquid crystal molecule 12111 close to the center of the cholesteric liquid crystal layer 1211 and the central axis W1, so that the angle between the long axis of the cholesteric liquid crystal molecule 12111 and the central axis W1 is arranged in a gradient in the direction away from the center of the cholesteric liquid crystal layer 1211, thereby causing different degrees of scattering of the incident light when passing through different areas in the cholesteric liquid crystal layer 1211. According to the PB phase principle, the tilt angle of the cholesteric liquid crystal molecule 12111 can add a spatially varying wavefront phase to the incident light wave, and this wavefront phase will change to different degrees as the molecular angle changes.

[0090] Specifically, the angle between the long axis of the cholesteric liquid crystal molecule 12111 near the center of the cholesteric liquid crystal layer 1211 and the central axis W1 is smaller, and the incident light is less affected by the wavefront phase and is easy to pass through, retaining more of its propagation direction. However, the angle between the long axis of the cholesteric liquid crystal molecule 12111 far from the center of the cholesteric liquid crystal layer 1211 is larger than the central axis W1, and the incident light is more likely to be scattered when passing through. This distribution pattern provides a natural gradient diffusion effect for the outgoing light, so that the outgoing light no longer presents a strong concentration, but forms a soft diffusion effect, which is similar to the effect of the optical diffusion film 122.

[0091] It can be understood that when the optical focal length is precisely controlled, the reflected light can achieve higher clarity and uniformity in the final imaging. The angle between the long axis of the cholesteric liquid crystal molecule 12111 and the central axis W1 is arranged in a gradient in the direction away from the center of the cholesteric liquid crystal layer 1211. This gradient change design can more effectively guide the scattering of light, making the image clearer in the display system and the brightness distribution more uniform.

[0092] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0093] The above is a detailed introduction to a display device provided in an embodiment of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A display device, characterized in that: include: A display module, used for emitting display light; A dimming structure, arranged on a light-emitting path of the display module, the dimming structure is used to receive the display light and reflect the display light onto a target imaging structure; Wherein, the dimming structure comprises a cholesteric liquid crystal layer, and the cholesteric liquid crystal layer is used to control the light output angle or optical focal length of the reflected light.

2. The display device according to claim 1, characterized in that The cholesteric liquid crystal layer includes a first cholesteric liquid crystal sublayer, a second cholesteric liquid crystal sublayer and a third cholesteric liquid crystal sublayer which are stacked, the first cholesteric liquid crystal sublayer reflects a first color light, the second cholesteric liquid crystal sublayer reflects a second color light, and the third cholesteric liquid crystal sublayer reflects a third color light; wherein the first color, the second color and the third color are different colors.

3. The display device according to claim 2, characterized in that: The wavelength of the third color light is shorter than the wavelength of the second color light, and the wavelength of the second color light is shorter than the wavelength of the first color light; The thickness of the third cholesteric liquid crystal sublayer is greater than the thickness of the second cholesteric liquid crystal sublayer, and the thickness of the second cholesteric liquid crystal sublayer is greater than the thickness of the first cholesteric liquid crystal sublayer.

4. The display device according to any one of claims 1 to 3, characterized in that: The dimming structure includes a first alignment layer, the first alignment layer is arranged on one side of the cholesteric liquid crystal layer, the first alignment layer includes a plurality of first alignment portions, and the plurality of first alignment portions are sequentially arranged in a direction away from the center of the first alignment layer; The pretilt angle of the first alignment portion far from the center of the alignment layer is different from the pretilt angle of the first alignment portion close to the center of the alignment layer.

5. The display device according to claim 4, characterized in that: The cholesteric liquid crystal layer includes a plurality of cholesteric liquid crystal molecules; The helical axis tilt angle of the cholesteric liquid crystal molecules far from the center of the cholesteric liquid crystal layer is greater than the helical axis tilt angle of the cholesteric liquid crystal molecules close to the center of the cholesteric liquid crystal layer.

6. The display device according to any one of claims 1 to 3, characterized in that: The dimming structure includes a diffusion film, which is arranged on a side of the cholesteric liquid crystal layer close to the display module, and covers the cholesteric liquid crystal layer.

7. The display device according to claim 6, characterized in that: The size of the diffusion film in the first direction is greater than the size of the diffusion film in the second direction, the diffusion film has a first diffusion angle in the first direction, and the diffusion film has a second diffusion angle in the second direction; The first diffusion angle is greater than or equal to 5 degrees and less than or equal to 25 degrees, and the second diffusion angle is greater than or equal to 5 degrees and less than or equal to 15 degrees.

8. The display device according to claim 6, characterized in that: The dimming structure comprises a first alignment layer, and the first alignment layer is arranged on a side of the cholesteric liquid crystal layer away from the diffusion film; The diffusion film includes a liquid crystal layer, the liquid crystal layer includes a plurality of liquid crystal molecules, and an orthographic projection of the liquid crystal layer on the first alignment layer is located in the first alignment layer.

9. The display device according to claim 1, characterized in that: The dimming structure comprises a first substrate and a second substrate arranged opposite to each other, the cholesteric liquid crystal layer is arranged between the first substrate and the second substrate, the cholesteric liquid crystal layer comprises a plurality of cholesteric liquid crystal molecules, and the long axes of the cholesteric liquid crystal molecules are arranged parallel to the horizontal plane where the first substrate is located; In the third direction, the arrangement of the plurality of cholesteric liquid crystal molecules changes periodically in a first direction perpendicular to the third direction; wherein the third direction is a direction perpendicular to the cholesteric liquid crystal layer, and the first direction is arranged perpendicular to the third direction.

10. The display device according to claim 9, characterized in that: The second substrate includes a central axis extending along a first direction; In one period, the angle between the long axis and the central axis of the cholesteric liquid crystal molecules far from the center of the cholesteric liquid crystal layer is greater than the angle between the long axis and the central axis of the cholesteric liquid crystal molecules close to the center of the cholesteric liquid crystal layer.

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