Display device and vehicle-mounted monitoring system

Abstract

Provided in the present application are a display device and a vehicle-mounted monitoring system. The display device comprises a first backlight module, a second backlight module, a liquid crystal cell and a sensing element. The second backlight module comprises a dimming layer and a backlight source, wherein a light emitting side of the backlight source faces the dimming layer, and light rays emitted by the backlight source are scattered by a light scattering area of the dimming layer and are then transmitted to a display surface. The sensing element receives infrared light that passes through a light-transparent area of the dimming layer, wherein the infrared light is transmitted to the side of the second backlight module away from the liquid crystal cell through the light-transparent area.

Description

Display device and vehicle monitoring system

[0001] This application claims priority to Chinese patent application No. 202311580875.9 filed on November 23, 2023, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present invention relates to the field of display technology, and in particular to a display device and a vehicle-mounted monitoring system. Background Art

[0003] The Driver Monitor System (DMS) is mainly used for driver fatigue monitoring. With the gradual maturity of autonomous driving, vehicle networking and related technologies, it has gradually evolved and iterated with more functions. Among them, considering the protection of personal privacy, it is necessary to avoid direct collection of human images in the visible light range as much as possible and hide the sensors as much as possible.

[0004] Currently, the most commonly used method is to use an active infrared sensor to collect infrared light information in the 940±10nm band, thereby realizing functions such as driver status monitoring and meeting the needs of the driver status monitoring system. At the same time, drawing on the camera under panel (CUP) technology widely used in mobile phones, the infrared receiving sensor is hidden under the display panel. Although the display device with an under-screen infrared receiving sensor can display information, the corresponding area of ​​the CUP cannot be displayed normally, so the display device cannot achieve full-screen display. Summary of the Invention

[0005] The embodiments of the present application provide a display device and a vehicle-mounted monitoring system. The display device can not only receive infrared light but also realize full-screen display.

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

[0007] Liquid crystal box,

[0008] a first backlight module, the first backlight module being disposed on the liquid crystal cell and having a through hole;

[0009] a second backlight module, the second backlight module being arranged on a side of the first backlight module away from the liquid crystal cell, the second backlight module being arranged corresponding to the through hole, the second backlight module comprising a dimming layer and a backlight source, the dimming layer being provided with a light-transparent area and a light-scattering area; the backlight source being arranged on a peripheral side of the dimming layer, with a light-emitting side of the backlight source facing the dimming layer, and light emitted by the backlight source being scattered by the light-scattering area of ​​the dimming layer and then emitted toward the liquid crystal cell through the through hole;

[0010] A sensor element is provided on a side of the second backlight module away from the first backlight module, and is used for receiving infrared light passing through the through hole and the light transparent area.

[0011] The present application also proposes a vehicle-mounted monitoring system, which includes a display device and a monitoring device, wherein the display device is electrically connected to the monitoring device, and the display device includes:

[0012] Liquid crystal box,

[0013] a first backlight module, the first backlight module being disposed on the liquid crystal cell and having a through hole;

[0014] a second backlight module, the second backlight module being arranged on a side of the first backlight module away from the liquid crystal cell, the second backlight module being arranged corresponding to the through hole, the second backlight module comprising a dimming layer and a backlight source, the dimming layer being provided with a light-transparent area and a light-scattering area; the backlight source being arranged on a peripheral side of the dimming layer, with a light-emitting side of the backlight source facing the dimming layer, and light emitted by the backlight source being scattered by the light-scattering area of ​​the dimming layer and then emitted toward the liquid crystal cell through the through hole;

[0015] A sensor element is provided on a side of the second backlight module away from the first backlight module, and is used for receiving infrared light passing through the through hole and the light transparent area. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] FIG1 is a schematic diagram of a first structure of a display device provided in an embodiment of the present application.

[0017] FIG2 is a schematic diagram of a second structure of a display device provided in an embodiment of the present application.

[0018] FIG3 is a schematic diagram of a first structure of a backlight module provided in an embodiment of the present application from a first viewing angle.

[0019] FIG4 is a schematic diagram of a first structure of a backlight module provided in an embodiment of the present application from a second viewing angle.

[0020] FIG5 is a schematic diagram of a second structure of a backlight module provided in an embodiment of the present application from a first viewing angle.

[0021] FIG6 is a schematic diagram of a second structure of a backlight module provided in an embodiment of the present application from a second viewing angle.

[0022] FIG7 is a schematic diagram of a third structure of a backlight module provided in an embodiment of the present application from a first viewing angle.

[0023] FIG8 is a schematic diagram of a third structure of a backlight module provided in an embodiment of the present application from a second viewing angle.

[0024] FIG9 is a schematic diagram of a fourth structure of the display device provided in an embodiment of the present application.

[0025] FIG10 is a schematic diagram of a fourth structure of a backlight module provided in an embodiment of the present application. Modes for Carrying Out the Invention

[0026] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a 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 this application. In addition, it should be understood that the specific embodiments described herein are only used to illustrate and explain the present application and are not intended to limit the present application.

[0027] In the description of this application, it should be understood that the terms "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0028] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, features defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "plurality" means two or more, and "at least one" means one, two, or more, unless otherwise specifically defined.

[0029] With the rapid development of cloud computing, big data, artificial intelligence, and core device technologies, and the application of various interactive technologies on in-vehicle displays, smart car connectivity is opening up new possibilities for modern intelligent vehicles. Public transportation safety is crucial for drivers and passengers, and their behavior plays a significant role. To monitor driver behavior, driver monitoring systems (DMSs) are installed in relevant intelligent vehicles. Their core function is to monitor driver fatigue and distraction, providing real-time monitoring of the vehicle's interior to determine the driver's current state.

[0030] The DMS system's optical camera and infrared receiving sensor, also known as an infrared camera, are located in locations such as the steering wheel, dashboard, or A-pillar. Under-screen infrared camera technology places the infrared camera below the display device's liquid crystal box, such as the LCD panel. Infrared light from an internal infrared source illuminates people and objects inside the vehicle, creating diffuse reflections. The infrared light is then received by the under-screen infrared camera, enabling full-screen display while simultaneously monitoring the vehicle's interior. The under-screen infrared camera display can display information without obstructing the driver's field of view, preventing accidents caused by obstructed vision. The development of this technology is driving the development of full-screen displays, in-vehicle displays, and ultimately public transportation safety.

[0031] Currently, the blind hole display technology widely used in mobile phones is used to hide the infrared receiving sensor under the display panel. Although the display device with the under-screen infrared receiving sensor can display information, the corresponding area of ​​the CPU cannot display normally, so the display device cannot achieve a full-screen display.

[0032] If the display device needs to achieve full-screen display function, the CUP area must have high infrared transmittance, and the CUP area can display normally. For the CUP of the liquid crystal display panel, it is necessary to provide a backlight for the CUP area, and the backlight must have high infrared transmittance.

[0033] In response to the above problems and objectives, embodiments of the present application provide a display device and a vehicle-mounted monitoring system, wherein the display device can receive infrared light and also realize full-screen display, as described below with reference to the accompanying drawings.

[0034] 1 and 2 , an embodiment of the present application provides a display device 100 . The display device 100 includes a liquid crystal cell 20 , a first backlight module 40 , a second backlight module 10 , and a sensor element 30 .

[0035] The first backlight module 40 is disposed on the liquid crystal cell 20 and is aligned with the liquid crystal cell 20. A through hole 41 is provided on the first backlight module 40.

[0036] The first backlight module 40 is a common backlight module in the related art and can be an edge-lit backlight or a direct-lit backlight. Since the first backlight module 40 is substantially opaque to infrared light, a through hole 41 is provided in the first backlight module 40 at least in the area corresponding to the sensor element 30. The through hole 41 corresponds to the CPU area of ​​the display device 100.

[0037] The second backlight module 10 is disposed on a side of the first backlight module 40 away from the liquid crystal cell. The second backlight module 10 is disposed corresponding to the through hole 41 . The through hole 41 is used to pass infrared light and light scattered by the light scattering region 112 of the dimming layer 11 .

[0038] Referring to Figures 3 and 4 , the second backlight module 10 includes a dimming layer 11 and a backlight source 12. The dimming layer 11 is provided with a light-transparent region 111 and a light-scattering region 112. The backlight source 12 is disposed around the dimming layer 11, with its light-emitting side facing the dimming layer. Light emitted by the backlight source is scattered by the light-scattering region 112 of the dimming layer 11 and then emitted toward the liquid crystal cell 20 through the through hole 41.

[0039] The dimming layer 11 has a first surface, a second surface and multiple side surfaces. The first surface and the second surface are arranged opposite to each other along the thickness direction of the dimming layer 11, and the multiple side surfaces are respectively connected to the first surface and the second surface. The backlight source 12 is arranged on at least one side surface of the dimming layer 11. For example, the backlight source 12 can be arranged on two opposite side surfaces or on two adjacent side surfaces. The backlight source 12 can be a light bar. The light bar can be one or more. The backlight source 12 is a side-entry backlight. When the second backlight module 10 is working, the light emitted by the backlight source 12 enters the dimming layer 11 from the side surface of the dimming layer 11, and then emits the dimming layer 11 from the first surface and / or second surface of the dimming layer 11. In order to further improve the uniformity of light, the dimming layer 11 is provided with a light transparent area 111 and a light scattering area 112. After the backlight source 12 enters the dimming layer 11, it is totally reflected or transmitted in the light transparent area 111, and is strongly scattered in the light scattering area 112 to form a surface light source, which can provide uniform backlight to the liquid crystal box 20 arranged above the second backlight module 10.

[0040] It is worth noting that the light-transparent region 111 is a region that does not change the propagation direction of light within it, and the light-scattering region 112 is a region that can scatter light within it. However, the refraction or reflection that occurs when light enters or exits the light-transparent region 111 or the light-scattering region 112 is not included in the above definitions of the light-transparent region 111 and the light-scattering region 112.

[0041] The liquid crystal cell 20 is disposed on the second backlight module 10 along its thickness. As described above, light emitted by the backlight source 12 is scattered by the light-scattering region 112 of the dimming layer 11 and then directed toward the liquid crystal cell 20. Due to the high uniformity of light emitted by the light-scattering region 112, a surface light source is formed on the first or second surface of the dimming layer 11. When the liquid crystal cell 20 is disposed on the first or second surface of the dimming layer 11, light emitted by the dimming layer 11 is uniformly directed toward the liquid crystal cell 20, enabling the liquid crystal cell 20 to display an image.

[0042] The sensor element 30 is disposed on a side of the second backlight module 10 away from the liquid crystal cell 20. That is, the liquid crystal cell 20 and the sensor element 30 are disposed on either side of the second backlight module 10, namely, on the first surface and the second surface, respectively. The sensor element 30 is disposed on the second backlight module 10 along the thickness direction of the second backlight module 10. The sensor element 30 may be an infrared receiving sensor. External infrared light can pass through the liquid crystal cell 20, the through hole 41, and the light-transparent region 111 in the dimming layer 11. That is, the infrared light is emitted through the light-transparent region 111 toward the side of the second backlight module 10 away from the liquid crystal cell 20, so that the sensor element 30 can receive the infrared light that passes through the through hole 41 and the light-transparent region 111. Infrared light refers to light in the infrared band.

[0043] Therefore, the display device 100 in the embodiment of the present application hides the sensor element 30 under the liquid crystal box 20 and the first backlight module 40, and adds a second backlight module 10 with the ability to penetrate infrared light between the first backlight module 40 and the sensor element 30, so that the sensor element 30 below can monitor the situation inside the vehicle in real time through the second backlight module 10, and at the same time, the backlight can provide display backlight for display, thereby realizing full-screen display.

[0044] In some embodiments, please continue to refer to FIG. 3 . The dimming layer 11 includes a first substrate 113, a haze adjustment layer 114, and a second substrate 115. The first substrate 113 and the second substrate 115 are disposed opposite each other. The haze adjustment layer 114 is disposed between the first substrate 113 and the second substrate 115. The haze adjustment layer 114 comprises at least a first partial region 116 and a second partial region 117. The first partial region 116 is a light-transparent region 111, and the second partial region 117 is a light-scattering region 112.

[0045] The first substrate 113 and the second substrate 115 may be made of glass or polyethylene terephthalate having high light transmittance.

[0046] The haze adjustment layer 114 is a plate-like structure having a third surface and a fourth surface along the thickness direction of the second backlight module 10. The first substrate 113 is disposed on the third surface, and the second substrate 115 is disposed on the fourth surface. The first partial region 116 and the second partial region 117 both extend through the third and fourth surfaces of the haze adjustment layer 114, allowing infrared light to pass from the first partial region 116 to the sensor element 30 and light generated by the backlight source 12 to be scattered in the second partial region 117 to form a surface light source that illuminates the liquid crystal cell 20.

[0047] In some embodiments, the first partial region 116 may be a columnar region, such as a cylindrical or prism-shaped region. The first partial region 116 may be distributed in an array or irregularly in the haze adjustment layer 114 , and the rest of the haze adjustment layer 114 is the second partial region 117 .

[0048] In some embodiments, the second partial region 117 may be a columnar region, such as a cylindrical or prism-shaped region. The second partial region 117 may be distributed in an array or irregularly in the haze adjustment layer 114 , and the rest of the haze adjustment layer 114 is the first partial region 116 .

[0049] The material of the haze adjustment layer 114 includes polymer dispersed liquid crystal (PDLC), polymer network liquid crystal (PNLC), focal-conic state of cholesteric liquid crystal, and other haze controllable materials.

[0050] The haze or transparency of the haze-adjusting layer 114 changes under the action of voltage, ultraviolet light, or heat. It is understood that when the haze of a portion of the haze-adjusting layer 114 is zero or the transparency is greater than or equal to a preset value, that portion is the light-transparent region 111; and when the haze of a portion of the haze-adjusting layer 114 is greater than or equal to a preset value or the transparency is less than or equal to a preset value, that portion is the light-scattering region 112.

[0051] In the embodiment of the present application, the haze adjustment layer 114 is divided into a first portion 116 and a second portion 117. The first portion 116 of the haze adjustment layer 114 is pre-irradiated with ultraviolet light, heated, or other corresponding methods using a matching mask to increase the transparency of the second portion 117 while maintaining the haze of the first portion 116. Alternatively, the second portion 117 of the haze adjustment layer 114 is pre-irradiated with ultraviolet light, heated, or other corresponding methods using a matching mask to increase the haze of the second portion 117 while maintaining the transparency of the first portion 116. The haze adjustment layer 114 is disposed between the first substrate 113 and the second substrate 115 to form the dimming layer 11.

[0052] Relatively speaking, in the embodiment of the present application, the haze adjustment layer 114 is formed only by partitioning processing, and no additional structure is required to enable the first partial area 116 to penetrate infrared light, and the second partial area 117 to evenly distribute the light of the backlight source 12 to form a surface light source, thereby saving more energy and improving work efficiency.

[0053] In some embodiments, electrodes are added to the second backlight module 10 to apply voltage to enhance the stability of the haze adjustment layer 114 .

[0054] Please refer to Figures 5 and 6. In the first case, the second backlight module 10 includes a first electrode 13 and a second electrode 14. The first electrode 13 and the second electrode 14 are respectively arranged on both sides of the first partial area 116 of the haze adjustment layer 114. The first electrode 13 is arranged between the first partial area 116 of the haze adjustment layer 114 and the first substrate 113. The second electrode 14 is arranged between the first partial area 116 of the haze adjustment layer 114 and the second substrate 115. The first electrode 13 and the second electrode 14 are used to apply an electric field to the first partial area 116 to form a light transparent area 111.

[0055] The material of the haze adjustment layer 114 is in a hazy state when no voltage is applied.

[0056] Taking the material of the haze adjustment layer 114 as an example, the specific principle of the PDLC haze adjustment layer 114 adjusting light is as follows: in the absence of an external voltage, the PDLC haze adjustment layer 114 cannot form a regular electric field, the optical axis orientation of the liquid crystal particles is random and disordered, and its effective refractive index n0 is not consistent with the refractive index n0 of the polymer. pThe PDLC haze adjustment layer 114 is opaque or translucent due to the strong scattering of incident light. When an external voltage is applied, the optical axes of the liquid crystal particles align perpendicular to the film surface, aligning with the direction of the electric field. The refractive index of the liquid crystal particles is substantially matched to that of the polymer, with no apparent interface, forming a substantially uniform medium. Therefore, incident light is not scattered, and the PDLC haze adjustment layer 114 appears transparent. Therefore, under the control of an applied electric field, the PDLC haze adjustment layer 114 exhibits optical switching properties. Therefore, by adjusting the voltage applied to the PDLC haze adjustment layer 114, the PDLC haze adjustment layer 114 can be adjusted to different haze states. For example, when no voltage is applied, the layer appears completely hazy. Applying 1V results in a slightly more transparent state, while applying 3V further increases the transparency, and finally reaching 10V, where it becomes completely transparent. The haze of the PDLC haze adjustment layer 114 can be adjusted as needed to achieve varying degrees of scattering of incident light, thereby adjusting the light output quality.

[0057] The process of forming the first electrode 13 or the second electrode 14 on both sides of the haze adjustment layer 114 is as follows: Taking the formation of the first electrode 13 as an example, a layer of indium tin oxide is first laid flat on one side of the haze adjustment layer 114. A conventional process flow, such as mask exposure, development, and etching, is then used to form the first electrode 13 corresponding to the first partial region 116. Through mask exposure and etching processes, the indium tin oxide in areas other than the first partial region 116 is removed, and the liquid crystal corresponding to the second partial region 117 maintains its original disordered state.

[0058] It is understood that by providing the first electrode 13 and the second electrode 14, a stable electric field is continuously applied to the first partial region 116 to maintain a transparent state, while the second partial region 117 is not subjected to an electric field and exhibits an atomized state. In the embodiment of the present application, the first electrode 13 and the second electrode 14 provide a stable voltage to maintain the transparency of the first partial region 116, allowing infrared light to pass through the first partial region 116, facilitating the sensor element 30 to receive external infrared light. The second partial region 117, where no voltage is applied, acts as a uniform light source, providing a surface light source for the liquid crystal cell 20.

[0059] In some embodiments, since the transparency of the first partial region 116 is adjustable, when the sensor element 30 is not needed or is not operating, it is not necessary for external infrared light to pass through the first partial region 116 and be received by the sensor element 30. The first electrode 13 and the second electrode 14 of the first partial region 116 can be inoperative, so that the first partial region 116 and the second partial region 117 are in a fogged state, thereby making the brightness of the light presented to the liquid crystal cell 20 more uniform and improving the display effect.

[0060] In the second case, please refer to Figures 7 and 8, the second backlight module 10 includes a third electrode 15 and a fourth electrode 16, and the third electrode 15 and the fourth electrode 16 are respectively arranged on both sides of the second partial area 117 of the haze adjustment layer 114, the third electrode 15 is arranged between the second partial area 117 of the haze adjustment layer 114 and the first substrate 113, and the fourth electrode 16 is arranged between the second partial area 117 of the haze adjustment layer 114 and the second substrate 115, and the third electrode 15 and the fourth electrode 16 are used to apply an electric field to the second partial area 117 to form a light scattering area 112.

[0061] The material of the haze adjustment layer 114 is transparent when no voltage is applied.

[0062] The third electrode 15 and the fourth electrode 16 are made of indium tin oxide (ITO). The preparation method is similar to that of the first electrode 13 described above and will not be further described here. The third electrode 15 and the fourth electrode 16 are made of indium tin oxide (ITO). ITO has a high transmittance for visible light (>90%, ~50nm), but its transmittance for near-infrared light (940nm) is relatively low (~80%). Through processes such as mask exposure and etching, the ITO in areas other than the second portion 117 is removed, and the liquid crystal corresponding to the second portion 117 is maintained in an ordered, highly transmittance state, thereby improving the transmittance of infrared light.

[0063] It is understood that by providing the third electrode 15 and the fourth electrode 16, a stable electric field is continuously applied to the second partial region 117 to maintain the atomized state, while the second partial region 117 is transparent when no electric field is applied. In the embodiment of the present application, the third electrode 15 and the fourth electrode 16 provide a stable voltage to maintain the atomized state of the second partial region 117, and the second partial region 117 acts as a uniform light source, providing a surface light source for the liquid crystal cell 20. The first partial region 116, where no voltage is applied, allows infrared light to pass through it, facilitating the sensor element 30 to receive external infrared light.

[0064] In some cases, since the haze of the second partial area 117 is adjustable, in order to improve the sensitivity of the infrared receiving device, that is, to receive more infrared light, the haze of the second partial area 117 can be reduced by reducing the voltage of the third electrode 15 and the fourth electrode 16 or stopping the pressure, so that the second partial area 117 is transparent, that is, the first partial area 116 and the second partial area 117 are transparent, so that more infrared light passes through the first partial area 116 and the second partial area 117 and is received by the sensing element 30, thereby improving sensitivity.

[0065] Since the through hole 41 provided on the first backlight module 40 may destroy the integrated display effect, to improve the integrated display effect of the display device 100 , please refer to FIG. 9 . The display device 100 further includes a diffusion film 50 provided between the backlight module and the liquid crystal cell 20 .

[0066] A full-surface diffusion film 50 is inserted between the first backlight module 40 and the liquid crystal cell 20. This diffusion film 50 has high infrared light transmittance and can be a 3M high-transmittance infrared diffuser or a low-haze scattering liquid crystal film. This diffusion film 50 not only improves the display edge caused by the through-holes 41 provided in the first backlight module 40, but also ensures uniformity in the display of the display device 100, achieving a better full-screen effect while also maintaining high infrared transmittance.

[0067] In some embodiments, as described above, light emitted by the backlight source 12 is scattered by the light-scattering regions 112 of the dimming layer 11 and then illuminates the liquid crystal cell 20. The liquid crystal cell 20 is only disposed on one surface of the dimming layer 11, and the light-scattering regions 112 can be disposed on both the first and second surfaces of the dimming layer 11 to form a surface light source. If the liquid crystal cell 20 is only disposed on the first surface of the dimming layer 11, the surface light source formed by the light-scattering regions 112 on the second surface is ineffective light. Therefore, in order to reduce ineffective light and improve light utilization, the display device 100 further includes a reflective film disposed on a side of the second backlight module 10 away from the liquid crystal cell 20. The reflective film is disposed corresponding to the light-scattering regions 112 to reflect light emitted by the backlight source 12 to one side of the liquid crystal cell 20, further improving light utilization. It is worth noting that the reflective film is only disposed corresponding to the light-scattering region and is not disposed correspondingly on the light-transparent region, thereby ensuring that infrared light can pass smoothly through.

[0068] Because the light scattering region 112 has a high degree of uniformity, a surface light source can be formed on the first or second surface of the dimming layer 11. When the liquid crystal cell 20 is disposed on the first or second surface of the dimming layer 11, the light emitted by the dimming layer 11 can evenly illuminate the liquid crystal cell 20, allowing the liquid crystal cell 20 to display an image.

[0069] In some embodiments, please refer to FIG10 , there are multiple light scattering regions 112, and the greater the distance between the light scattering region 112 and the backlight source 12, the lower the density of the light scattering region 112. In the first backlight module 40, since the backlight source 12 is a side-entry light source, the intensity of the light generated by the backlight source 12 will continue to weaken during the process of propagating toward the middle. In order to maintain the brightness uniformity of the second backlight module 10, the distribution density of the light scattering region 112 in the second backlight module 10 needs to be adjusted, that is, the density is high at the position far from the backlight source 12, and the density is low at the position close to the light scattering region 112, so as to maintain the uniformity of the light output brightness of the entire first backlight module 40. In the actual design process, the size and specific density distribution of the light scattering region 112 can be simulated by optical simulation software.

[0070] In some embodiments, referring to Figures 3, 6, and 8, the orthographic projection of the light-transparent region 111 onto the liquid crystal cell 20 is circular. In other words, the light-transparent region 111 is cylindrical. Considering the impact on infrared imaging and avoiding diffraction interference, a circular orthographic projection of the light-transparent region 111 onto the liquid crystal cell 20 achieves the best results.

[0071] In some embodiments, the thickness of the second backlight module 10 is 5 microns to 50 microns, such as 20 microns, 25 microns, 30 microns, etc. The relatively small thickness of the second backlight module 10 is conducive to making the display device 100 thinner and lighter.

[0072] The embodiment of the present application further provides a vehicle-mounted monitoring system for use in a smart car. The vehicle-mounted monitoring system includes the display device 100 and a monitoring device, wherein the display device 100 is electrically connected to the monitoring device, and the monitoring device is configured to receive infrared data transmitted by the display device 100.

[0073] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0074] The above is a detailed introduction to the technical solutions provided in the embodiments of the present application. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the technical solutions and core ideas of the present application. Ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A display device, comprising: Liquid crystal box, a first backlight module, wherein the first backlight module is disposed on the liquid crystal box and a through hole is disposed on the first backlight module; A second backlight module, the second backlight module is arranged on a side of the first backlight module away from the liquid crystal box, the second backlight module is arranged corresponding to the through hole, the second backlight module comprises a dimming layer and a backlight source, the dimming layer is provided with a light transparent area and a light scattering area; the backlight source is arranged on the peripheral side of the dimming layer, the light emitting side of the backlight source faces the dimming layer, and the light emitted by the backlight source is scattered by the light scattering area of ​​the dimming layer and then emitted to the liquid crystal box through the through hole; A sensor element is arranged on a side of the second backlight module away from the first backlight module, and is used for receiving infrared light passing through the through hole and the light transparent area.

2. The display device according to claim 1, wherein: The dimming layer includes a first substrate, a haze adjustment layer and a second substrate. The first substrate and the second substrate are arranged opposite to each other, and the haze adjustment layer is arranged between the first substrate and the second substrate. The first partial area of ​​the haze adjustment layer is a light transparent area, and the second partial area is a light scattering area.

3. The display device according to claim 2, wherein: The second backlight module includes a first electrode and a second electrode, the first electrode and the second electrode are respectively arranged on both sides of a first partial area of ​​the haze adjustment layer, and the first electrode and the second electrode are used to apply an electric field to the first partial area to form the light transparent area.

4. The display device according to claim 2, wherein: The second backlight module includes a third electrode and a fourth electrode, the third electrode and the fourth electrode are respectively arranged on both sides of the second partial area of ​​the haze adjustment layer, and the third electrode and the fourth electrode are used to apply an electric field to the second partial area to form the light scattering area.

5. The display device according to claim 2, wherein: The material of the haze adjustment layer includes one or more of polymer dispersed liquid crystal, polymer network liquid crystal and focal conic state of cholesteric liquid crystal.

6. The display device according to claim 2, wherein: The first partial region and the second partial region include columnar regions.

7. The display device according to any one of claims 1 to 6, wherein: The display device further includes a diffusion film, and the diffusion film is arranged between the first backlight module and the liquid crystal box.

8. The display device according to claim 7, wherein: The display device further comprises a reflective film, which is arranged on a side of the second backlight module away from the liquid crystal box, and the reflective film is arranged corresponding to the light scattering area.

9. The display device according to any one of claims 1 to 6, wherein: There are multiple light scattering regions, and the density of the light scattering regions is lower when the distance between the light scattering regions and the backlight source is greater.

10. The display device according to any one of claims 1 to 6, wherein: The shape of the orthographic projection of the light transparent area on the liquid crystal box is a circle.

11. The display device according to any one of claims 1 to 6, wherein: The thickness of the second backlight module is 5 micrometers to 50 micrometers.

12. A vehicle monitoring system, wherein: It includes a display device and a monitoring device, the display device is electrically connected to the monitoring device, and the display device includes: Liquid crystal box, a first backlight module, wherein the first backlight module is disposed on the liquid crystal box and a through hole is disposed on the first backlight module; A second backlight module, the second backlight module is arranged on a side of the first backlight module away from the liquid crystal box, the second backlight module is arranged corresponding to the through hole, the second backlight module comprises a dimming layer and a backlight source, the dimming layer is provided with a light transparent area and a light scattering area; the backlight source is arranged on the peripheral side of the dimming layer, the light emitting side of the backlight source faces the dimming layer, and the light emitted by the backlight source is scattered by the light scattering area of ​​the dimming layer and then emitted to the liquid crystal box through the through hole; A sensor element is arranged on a side of the second backlight module away from the first backlight module, and is used for receiving infrared light passing through the through hole and the light transparent area.

13. The vehicle-mounted monitoring system according to claim 12, wherein: The dimming layer includes a first substrate, a haze adjustment layer and a second substrate. The first substrate and the second substrate are arranged opposite to each other, and the haze adjustment layer is arranged between the first substrate and the second substrate. The first partial area of ​​the haze adjustment layer is a light transparent area, and the second partial area is a light scattering area.

14. The vehicle-mounted monitoring system according to claim 13, wherein: The second backlight module includes a first electrode and a second electrode, the first electrode and the second electrode are respectively arranged on both sides of a first partial area of ​​the haze adjustment layer, and the first electrode and the second electrode are used to apply an electric field to the first partial area to form the light transparent area.

15. The vehicle-mounted monitoring system according to claim 13, wherein: The second backlight module includes a third electrode and a fourth electrode, the third electrode and the fourth electrode are respectively arranged on both sides of the second partial area of ​​the haze adjustment layer, and the third electrode and the fourth electrode are used to apply an electric field to the second partial area to form the light scattering area.

16. The vehicle-mounted monitoring system according to claim 13, wherein: The material of the haze adjustment layer includes one or more of polymer dispersed liquid crystal, polymer network liquid crystal and focal conic state of cholesteric liquid crystal.

17. The vehicle-mounted monitoring system according to claim 13, wherein: The first partial region and the second partial region include columnar regions.

18. The vehicle-mounted monitoring system according to any one of claims 12 to 17, wherein: The display device further includes a diffusion film, and the diffusion film is arranged between the first backlight module and the liquid crystal box.

19. The vehicle-mounted monitoring system according to claim 18, wherein: The display device further comprises a reflective film, which is arranged on a side of the second backlight module away from the liquid crystal box, and the reflective film is arranged corresponding to the light scattering area.

20. The vehicle-mounted monitoring system according to any one of claims 12 to 17, wherein: There are multiple light scattering regions, and the density of the light scattering regions is lower when the distance between the light scattering regions and the backlight source is greater.

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