Image generation unit and display device

Abstract

The application provides an image generating unit and a display device. The image generating unit comprises a backlight module, a first liquid crystal panel, a second liquid crystal panel and a first polarizer; the first liquid crystal panel comprises a linear polarization structure, a first liquid crystal cell and a second polarizer arranged along the transmission direction of the outgoing light rays of the backlight module; the second liquid crystal panel comprises a second liquid crystal cell and a color filter; at least one of the components in the first liquid crystal panel, the first liquid crystal panel and the second liquid crystal panel, the components in the second liquid crystal panel and the second liquid crystal panel and the first polarizer is provided with an air gap with a preset width. The application uses a double-screen structure, the black-and-white first liquid crystal panel realizes regional dimming, which is beneficial to improving the contrast ratio; the color second liquid crystal panel removes the lower polarizer and is provided with a higher resolution, which is beneficial to improving the display effect; the structures are separated by a distance, the heat can circulate in the air, thereby enhancing the heat dissipation effect and reducing the heat.

Description

Technical Field

[0001] This application relates to the field of display technology, and in particular to an image generation unit and a display device. Background Technology

[0002] The Picture Generation Unit (PGU) is a core imaging component in optical display devices such as televisions, head-up displays (HUDs), and virtual reality / augmented reality (VR / AR) systems. Its main function is to convert digital image signals into visible light images that can be projected or directly displayed by the optical system. It is a key module determining the overall resolution, brightness, contrast, power consumption, and operational stability of the device. Currently, mainstream PGU implementations include Liquid Crystal Display (LCD), Digital Light Processing (DLP), Liquid Crystal on Silicon (LCOS), and Laser Beam Scanning (LBS) technologies. Among these, the LCD solution is widely used in mid-to-high-end display and projection PGU systems due to its mature technology, controllable cost, and ease of resolution improvement.

[0003] Currently, a dual-screen LCD structure is used to improve resolution, but its transmittance is relatively low. To ensure its output brightness, the backlight power is increased accordingly, which leads to an increase in heat in the PGU system. In addition to the heat accumulation generated by the backlight, ambient light may also backflow and generate heat, causing heat to accumulate in the screen. When the temperature or heat is too high, it can cause the screen to burn out or the display effect to deteriorate. Therefore, there is an urgent need for a PGU display system that can improve contrast, has excellent heat dissipation performance, and can work continuously for a long time. Summary of the Invention

[0004] This application provides an image generation unit and a display device. The image generation unit uses a dual-screen structure. The first black-and-white liquid crystal panel can achieve local dimming, which is beneficial to improving contrast. The second color liquid crystal panel removes the lower polarizer and can be set to a higher resolution, which is beneficial to improving the display effect. An air gap is formed between each structure, which allows heat to flow in the air, thereby enhancing the heat dissipation effect and reducing heat.

[0005] According to one aspect of this application, an image generation unit is provided, including a backlight module, a first liquid crystal panel, a second liquid crystal panel, and a first polarizer sequentially disposed on the light-emitting side of the backlight module; The first liquid crystal panel includes a linear polarization structure, a first liquid crystal cell, and a second polarizer arranged sequentially along the light transmission direction of the backlight module. The second liquid crystal panel includes a second liquid crystal cell and a color filter arranged sequentially along the light transmission direction of the backlight module. The monochrome first liquid crystal panel and the color second liquid crystal panel are beneficial to improving contrast and resolution and enhancing display effect. An air gap of a preset width is provided between each component inside the first liquid crystal panel, between the first liquid crystal panel and the second liquid crystal panel, between each component inside the second liquid crystal panel, and at least one location between the second liquid crystal panel and the first polarizer, thereby facilitating heat dissipation.

[0006] Optionally, the linear polarization structure includes a reflective third polarizer, which is used to modulate the emitted light from the backlight module into target linearly polarized light to achieve the function of the first liquid crystal panel.

[0007] Optionally, the second polarizer is a reflective polarizer. The reflective polarizer, in conjunction with the air gap, enhances heat dissipation. The reflective polarizer can reflect some energy, reducing heat accumulation.

[0008] Optionally, the linear polarization structure further includes a single-set polarizing beam splitter and a half-wave plate disposed on the side of the reflective third polarizer near the backlight module. The half-wave plate is located in the reflected light path of the polarizing beam splitter. The emitted light from the backlight module includes first linearly polarized light and second linearly polarized light. The first linearly polarized light is transmitted through the polarizing beam splitter to the reflective third polarizer. The second linearly polarized light is reflected by the polarizing beam splitter and transmitted through the half-wave plate, then converted into first linearly polarized light and incident on the reflective third polarizer. The polarization direction of the first linearly polarized light is parallel to the polarization direction of the target linearly polarized light, and the polarization direction of the first linearly polarized light is perpendicular to the polarization direction of the second linearly polarized light. By setting the polarizing beam splitter and the half-wave plate, the second linearly polarized light in the backlight can also be utilized, improving backlight utilization efficiency, reducing energy loss, increasing screen brightness, enhancing display effect, and reducing the power of the LED chips in the backlight module, thus reducing the heat generated by the LED chips.

[0009] Optionally, the linear polarization structure includes a single set of polarizing beam splitters and a half-wave plate. The half-wave plate is located in the reflected light path of the polarizing beam splitter. The emitted light from the backlight module includes first linearly polarized light and second linearly polarized light. The first linearly polarized light is transmitted to the first liquid crystal panel through the polarizing beam splitter. The second linearly polarized light is reflected by the polarizing beam splitter and transmitted through the half-wave plate, then converted back into first linearly polarized light and incident on the first liquid crystal panel. The polarization direction of the first linearly polarized light is parallel to the polarization direction of the target linearly polarized light on the first liquid crystal panel, and the polarization direction of the first linearly polarized light is perpendicular to the polarization direction of the second linearly polarized light. By setting the polarizing beam splitter and the half-wave plate, the second linearly polarized light in the backlight can also be utilized, improving backlight utilization efficiency, reducing energy loss, increasing screen brightness, enhancing display effect, and reducing the power of the LED chips in the backlight module, thus reducing the heat generated by the LED chips.

[0010] Optionally, an optical functional layer may also be included, located between the backlight module and the first liquid crystal panel. Providing an optical functional layer helps improve backlight utilization.

[0011] Optionally, the optical functional layer includes at least one of a lens, a light-diffusing film, or a brightness-enhancing film.

[0012] Optionally, it also includes at least one reflector and a cover plate disposed on the light path emitted from the second liquid crystal cell, wherein the first polarizer is attached to the surface of the reflector or the surface of the cover plate near the second liquid crystal cell. The reflector can change the direction of light transmission, and the cover plate provides protection and reduces sunlight backflow, making it more suitable for HUD applications.

[0013] Optionally, the reflector includes a first reflector and a second reflector.

[0014] Optionally, both the first and second reflectors are curved reflectors.

[0015] Optionally, the resolution of the first liquid crystal panel is lower than the resolution of the second liquid crystal panel.

[0016] Optionally, the image generation unit includes at least one of a mechanical clamp, an inlay groove, or an adhesive tape, so that at least one location is formed between the components inside the first liquid crystal panel, between the first liquid crystal panel and the second liquid crystal panel, between the components inside the second liquid crystal panel, and between the second liquid crystal panel and the first polarizer.

[0017] Optionally, the mechanical clamp, the insert groove, and the adhesive tape include openings. Providing openings facilitates airflow and improves heat dissipation.

[0018] Optionally, the width of the air gap is less than or equal to 10 mm.

[0019] Optionally, the first LCD panel is a monochrome LCD panel, and the second LCD panel is a color LCD panel, which helps to improve contrast and resolution and enhance display effect.

[0020] According to another aspect of this application, a display device is provided, including the image generation unit described above.

[0021] Optionally, the display device is a vehicle-mounted HUD display device or a general-purpose liquid crystal display device.

[0022] The image generation unit provided in this application includes a backlight module, a first liquid crystal panel, a second liquid crystal panel, and a first polarizer arranged sequentially on the light-emitting side of the backlight module; the backlight module is used to provide backlight, the monochrome first liquid crystal panel can achieve local dimming, which is beneficial to improving contrast; the color second liquid crystal panel removes the lower polarizer and can be set to a higher resolution, which is beneficial to improving the display effect; the structures are separated by a distance to form an air gap, which allows heat to flow in the air, thereby enhancing the heat dissipation effect and reducing heat.

[0023] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this application, nor is it intended to limit the scope of this application. Other features of this application will become readily apparent from the following description. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the structure of an image generation unit in the prior art; Figure 2 A schematic diagram of the structure of an image generation unit provided in this application; Figure 3 A schematic diagram of a linear polarization structure provided in this application; Figure 4 A schematic diagram of another linear polarization structure provided in this application; Figure 5 A schematic diagram of another image generation unit provided in this application; Figure 6 A schematic diagram of the structure of another image generation unit provided in this application; Figure 7A schematic diagram of the structure of another image generation unit provided in this application; Figure 8 A schematic diagram of the structure of another image generation unit provided in this application; Figure 9 A schematic diagram of the structure of another image generation unit provided in this application; Figure 10 This is a schematic diagram of the structure of another image generation unit provided in this application. Detailed Implementation

[0026] To enable those skilled in the art to better understand the present application, the technical solutions of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present application.

[0027] It should be noted that the terminology used in this application is for the purpose of describing specific embodiments only and is not intended to limit the application. It should be noted that directional terms such as "above," "below," "left," and "right" used in this application are used to describe the angles shown in the accompanying drawings and should not be construed as limiting the application. Furthermore, in the context, it should be understood that when referring to an element being formed "above" or "below" another element, it can be formed not only directly "above" or "below" the other element, but also indirectly "above" or "below" the other element through intermediate elements. The terms "first," "second," etc., are used for descriptive purposes only and do not indicate any order, quantity, or importance, but are merely used to distinguish different components. It should be understood that such terms can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having”, and any variations thereof, are intended to cover non-exclusive inclusion, such that a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or apparatus.

[0028] Figure 1 This is a schematic diagram of the structure of an image generation unit in the prior art, with reference to... Figure 1The image generation unit includes a backlight module 1, a liquid crystal panel 2, and a liquid crystal panel 3 stacked sequentially. Liquid crystal panel 2 includes a lower polarizer 201, a liquid crystal cell 202, and an upper polarizer 203. Liquid crystal panel 3 includes a lower polarizer 301, a liquid crystal cell 302, and an upper polarizer 303. Adhesive, filter layers, and other film layers are not shown. The existing image generation unit structure has the following drawbacks: the backlight emitted from the backlight module 1 needs to pass through two screens sequentially. Due to factors such as polarizer absorption, the transmittance decreases, and heat accumulates. The polarizer and liquid crystal cell are tightly bonded, so when sunlight enters the system, it is directly focused into the liquid crystal through the polarizer, resulting in extremely high heat conduction efficiency. Because the liquid crystal has poor heat resistance, the heat generated by the polarizer cannot be dissipated in time, causing the screen to burn out when a certain temperature is reached. Furthermore, the PGU structure is compact, and heat dissipation is mainly concentrated below the backlight module 1, resulting in poor heat dissipation for the liquid crystal portion. Due to the reduced transmittance, heat accumulation occurs due to increased power to maintain brightness.

[0029] To address the aforementioned problems, this application provides an image generation unit, exemplarily, Figure 2 This is a schematic diagram of the structure of an image generation unit provided in this application, with reference to... Figure 2 The image generation unit includes a backlight module 10, a first liquid crystal panel 20, a second liquid crystal panel 30, and a first polarizer 40 arranged sequentially on the light-emitting side of the backlight module 10; the first liquid crystal panel 20 includes a linear polarization structure 21, a first liquid crystal cell 22, and a second polarizer 23 arranged sequentially along the light transmission direction of the backlight module 10; the second liquid crystal panel 30 includes a second liquid crystal cell 31 and a color filter 32 arranged sequentially along the light transmission direction of the backlight module 10; wherein, at least one location is provided between the components inside the first liquid crystal panel 20, between the first liquid crystal panel 20 and the second liquid crystal panel 30, between the components inside the second liquid crystal panel 30, and between the second liquid crystal panel 30 and the first polarizer 40, where an air gap of a preset width is provided.

[0030] The backlight module 10 provides backlighting and may include a substrate and multiple backlight sources located on one side of the substrate. The backlight sources can be light-emitting diodes (LEDs). The backlight module 10 can be a direct-lit backlight module or a side-lit backlight module, depending on the specific implementation. The polarizer may include a substrate and a functional layer. Figure 2Specific film layers are not shown. Compared with ordinary liquid crystal panels, the first liquid crystal panel 20 removes the color filter, that is, the first liquid crystal panel 20 is a black and white liquid crystal panel. Different areas of it can transmit white light of different gray levels according to actual needs, thereby realizing the local dimming function, which is beneficial to improving the contrast of the image generation unit. The second liquid crystal panel 30 is a color liquid crystal panel, which can be set with a higher resolution to improve the fineness of the displayed image. Since one area of ​​local dimming usually corresponds to multiple pixel areas, in one embodiment, optionally, the resolution of the first liquid crystal panel 20 is less than the resolution of the second liquid crystal panel 30. This setting can improve the resolution of the image generation unit and reduce costs. The linear polarization structure 21 converts the backlight emitted from the backlight module 10 into target linearly polarized light. The target linearly polarized light is incident on the first liquid crystal cell 22, that is, the polarization state of the target linearly polarized light is the polarization state required for the first liquid crystal panel 20 to work. The first liquid crystal cell 22 may include a lower substrate (array substrate, including pixel circuits formed by multiple thin film transistors), a liquid crystal layer and an upper substrate (protective cover plate), wherein Figure 2 The specific structure is not shown. The pixel circuit controls the rotation of the liquid crystal to control the polarization state of the light, and then the light passes through the second polarizer 23 to achieve brightness adjustment in different areas. Compared with the existing structure, the second liquid crystal panel 30 removes the lower polarizer (the polarizer on the side of the second liquid crystal substrate 30 closest to the first liquid crystal panel 20), which is beneficial to improve light transmittance and reduce heat absorption, thereby reducing heat. The color filter 32 may include a red filter, a green filter, and a blue filter to achieve color image display. It is understood that in this application, air gaps may be provided at one or more locations between the components inside the first liquid crystal panel 20 (e.g., between the linear polarization structure 21 and the first liquid crystal cell 22, between the first liquid crystal cell 22 and the second polarizer 23), between the first liquid crystal panel 20 and the second liquid crystal panel 30, between the components inside the second liquid crystal panel 30 (e.g., between the second liquid crystal cell 31 and the color filter 32), and between the second liquid crystal panel 30 and the first polarizer 40, or some components may not have air gaps (e.g., they may be bonded with optical adhesive). The specific implementation can be designed according to the actual situation. Figure 2In the illustrative embodiment shown, air gaps of a preset width are provided between the linear polarization structure 21 and the first liquid crystal cell 22, between the first liquid crystal cell 22 and the second polarizer 23, between the first liquid crystal panel 20 and the second liquid crystal panel 30, and between the color filter 32 and the first polarizer 40, thereby achieving good heat dissipation. To avoid light leakage, the color filter 32 is directly attached to the light-emitting surface of the second liquid crystal cell 31. In specific implementations, optionally, the width of the air gap is less than or equal to 10 mm to avoid excessively large image generation units while ensuring good heat dissipation. It is understood that in other embodiments, the number of air gaps can be designed according to actual conditions; for example, the linear polarization structure 21 and the first liquid crystal cell 22 can be directly attached, or the first liquid crystal panel 20 and the second liquid crystal panel 30 can be directly attached, etc., and this application does not limit this.

[0031] There are various ways to form air gaps. For example, optionally, the image generation unit includes at least one of mechanical clamps, inlay grooves, or tape, so that air gaps are formed between the components inside the first liquid crystal panel 20, between the first liquid crystal panel 20 and the second liquid crystal panel 30, between the components inside the second liquid crystal panel 30, and at least one location between the second liquid crystal panel 30 and the first polarizer 40.

[0032] In this embodiment, to prevent the structures in the dual screens from being tightly fitted together, mechanical clamps, mounting slots, or tape can be used to fix the liquid crystal cells and polarizers in the dual screens, leaving them a distance apart. This allows the polarizers to absorb the light reflected from external sunlight and the light emitted from the backlight module 10, preventing the converted heat from being rapidly transferred to the liquid crystal. Furthermore, the air gap between the structures allows heat to circulate, resulting in better heat dissipation, clearer display, and reduced screen burn-in. In practice, mechanical clamps or similar methods can be used to fix each structure of the dual screens, or both screens, or a single screen structure, depending on the actual design.

[0033] Furthermore, in another embodiment, optionally, the mechanical clamp, insert groove, and tape include openings. By providing openings in the mechanical clamp, insert groove, and tape, airflow within the air gap is facilitated, further improving heat dissipation performance.

[0034] The technical solution of this application uses a dual-screen structure. The black and white first liquid crystal panel can achieve local dimming, which is beneficial to improving the contrast. The color second liquid crystal panel removes the lower polarizer and can be set to a higher resolution, which is beneficial to improving the display effect. The structures are separated by a distance to form an air gap, which allows heat to flow in the air, thereby enhancing the heat dissipation effect and reducing heat.

[0035] In one embodiment, reference continues. Figure 2 Optionally, the linear polarization structure 21 includes a reflective third polarizer, which is used to modulate the emitted light from the backlight module 10 into target linearly polarized light.

[0036] A polarizer is an optical element that transmits light with one polarization direction (e.g., horizontally polarized p-light or vertically polarized s-light) while absorbing or reflecting light with another polarization direction (e.g., vertically polarized s-light or horizontally polarized p-light). It is primarily used to generate and control polarized light. By setting the linear polarization structure 21 as a reflective third polarizer, the target linearly polarized light required by the first liquid crystal panel can be generated. Furthermore, the reflective third polarizer can reflect non-transmissible polarized light without absorption, thereby reducing heat accumulation.

[0037] In existing technologies, polarizers in liquid crystal panels typically employ absorptive polarizers. Absorptive polarizers absorb light energy and generate heat, while reflective polarizers can reflect some of the energy. Therefore, in one embodiment, to reduce energy accumulation, the second polarizer can optionally be a reflective polarizer. The reflective polarizer, combined with an air gap, enhances heat dissipation. The first polarizer can be either an absorptive or reflective polarizer. Since the first polarizer is located at the emission end of the second liquid crystal panel, which is far from the backlight module, either an absorptive or reflective polarizer can be used.

[0038] Since the backlight emitted from the backlight module 10 can be circularly polarized light, when the linear polarization structure 21 is set as a polarizer, although the structure is simple, light loss will occur because some backlight is not utilized. In order to improve the backlight utilization efficiency, in another embodiment, optionally, the linear polarization structure includes a single set of polarizing beam splitters and a half-wave plate. The half-wave plate is located on the reflected light path of the polarizing beam splitter. The emitted light from the backlight module includes first linearly polarized light and second linearly polarized light. The first linearly polarized light is transmitted to the first liquid crystal panel through the polarizing beam splitter. The second linearly polarized light is converted into first linearly polarized light after being reflected by the polarizing beam splitter and transmitted by the half-wave plate and then incident on the first liquid crystal panel. The polarization direction of the first linearly polarized light is parallel to the polarization direction of the target linearly polarized light of the first liquid crystal panel, and the polarization direction of the first linearly polarized light is perpendicular to the polarization direction of the second linearly polarized light.

[0039] For example, Figure 3 This is a schematic diagram of a linear polarization structure provided in this application. Figure 3 The structure and principle of the linearly polarized structure are shown in the figure. (Refer to...) Figure 3The linear polarization structure includes a polarizing beam splitter 211 and a half-wave plate 212. The polarizing beam splitter 211 can be a polarizing beam splitter (PBS), with a beam-splitting film sealed on the inclined surface of the PBS. When the incident angle satisfies the Brewster angle condition, the reflectivity of p-polarized light is 0. By controlling the film layer, the reflectivity of s-polarized light is made close to 1. The incident light is split by the prism, and the p-polarized light (… Figure 3 The horizontal line indicates the polarization direction of p-polarized light, while s-polarized light (…) is transmitted. Figure 3 The center dot indicates the polarization direction of the s-polarized light. The reflected s-polarized light is then reflected again and converted into p-polarized light by the half-wave plate 212. The final output light is all p-polarized light, effectively reducing energy loss, increasing brightness, and reducing the power of the LED chips in the backlight module, thus reducing the heat generated by the LEDs.

[0040] It should be noted that in other embodiments, the same principle can be used to design the specific structure of the linear polarization structure, which may include, for example, a plane mirror. Figure 4 This is a schematic diagram of another linear polarization structure provided in this application, which also includes a plane mirror 213, which can be designed according to actual conditions in other embodiments.

[0041] Figure 5 This is a schematic diagram of another image generation unit provided in this application, to illustrate the structure of the unit. Figure 3 Taking the structure shown as an example, refer to Figure 5 The linear polarization structure 21 includes a polarizing beam splitter 211 and a half-wave plate 212. The half-wave plate 211 is located on the reflected light path of the polarizing beam splitter 211. The emitted light from the backlight module 10 includes first linearly polarized light (p-polarized light) and second linearly polarized light (s-polarized light). The emitted light can be circularly polarized light. The first linearly polarized light is transmitted to the first liquid crystal panel 20 through the polarizing beam splitter 211. The second linearly polarized light is reflected by the polarizing beam splitter 211 and transmitted by the half-wave plate 212, and then converted into first linearly polarized light and incident on the first liquid crystal panel 20.

[0042] In this embodiment, the lower polarizer of the first liquid crystal panel 20 is replaced with a PBS + half-wave plate. In other embodiments, a PBS, a half-wave plate, and a reflective third polarizer can also be set simultaneously. Optionally, the linear polarization structure also includes a single-group polarizing beam splitter and a half-wave plate disposed on the side of the reflective third polarizer near the backlight module. The half-wave plate is located on the reflected light path of the polarizing beam splitter. The emitted light from the backlight module includes first linearly polarized light and second linearly polarized light. The first linearly polarized light is transmitted through the polarizing beam splitter to the reflective third polarizer. The second linearly polarized light is reflected by the polarizing beam splitter and transmitted through the half-wave plate, and then converted into first linearly polarized light that is incident on the reflective third polarizer. The polarization direction of the first linearly polarized light is parallel to the polarization direction of the target linearly polarized light, and the polarization direction of the first linearly polarized light is perpendicular to the polarization direction of the second linearly polarized light. The specific implementation can be selected according to the actual situation.

[0043] Figure 6 This is a schematic diagram of the structure of another image generation unit provided in this application. Figure 6 In this embodiment, a PBS + half-wave plate is placed under the lower polarizer (reflective third polarizer) of the first liquid crystal panel 20. The backlight emitted from the backlight module is partially transmitted and partially reflected by the inclined beam-splitting film in the PBS. The reflected light is then converted into target linearly polarized light (p-polarized light) by the half-wave plate, which is consistent with the polarization direction required by the LCD. This reduces energy loss, reduces the heat generated by the lower polarizer absorbing light with inconsistent polarization direction, reduces heat accumulation on the screen, and can effectively improve brightness and enhance display effect.

[0044] Figure 7 This is a schematic diagram of the structure of another image generation unit provided in this application, with reference to... Figure 7 Optionally, the image generation unit also includes an optical functional layer 50 located between the backlight module 10 and the first liquid crystal panel 20.

[0045] The optical functional layer 50 can be used to adjust the beam quality of the backlight, such as focusing and homogenizing. In specific implementations, the optical functional layer 50 may optionally include at least one of a lens, a homogenizing film, or a brightness enhancement film. This application does not limit this, and the specific structure can be flexibly selected according to the actual situation.

[0046] The image generation unit provided in this application embodiment can be used in HUD scenarios. Since HUDs are usually used outdoors, in the prior art, the polarizer is tightly attached to the liquid crystal cell, and the polarizer is an absorptive polarizer with a certain absorption rate. When external sunlight flows back into the HUD system, the light passes through a series of optical devices or backlight module lamp beads and its heat is absorbed by the upper and lower polarizers. The heat generated after absorption is quickly conducted to the liquid crystal through the polarizing substrate, and the heat conduction efficiency is extremely high. When the temperature or heat is too high, it will cause the screen to burn out or the display effect to deteriorate and the contrast to decrease. To reduce temperature and screen burn-in, and extend screen life, existing solutions typically add polarizing films to other parts of the PGU (Power Gauge Unit) to prevent backlight lamps from overheating, in addition to the upper and lower polarizers used in the LCD structure. They also add polarization absorption to the HUD cover film to prevent sunlight backflow into the system. However, this results in redundant polarizer absorption and HUD cover film polarization properties, meaning only one layer of structure is effective, failing to provide dual heat reduction. Furthermore, the cover film layer is expensive. Similarly, the lower polarizer on the LCD and the polarizer + substrate below it also have redundant properties, with only one layer absorbing some of the heat from the backlight lamps. Because liquid crystals have poor heat resistance, the heat absorbed by the polarizers cannot be dissipated quickly enough, leading to screen burn-in when a certain temperature is reached. Moreover, the PGU structure is compact, with heat dissipation mainly concentrated below the lamp board, resulting in poor heat dissipation for the liquid crystal portion. Therefore, in another embodiment, the upper polarizer of the color LCD screen (the upper polarizer substrate can be removed) can be taken out and attached to any position in the HUD system, such as a reflector or a cover plate, or the upper polarizer and substrate can be fixed under the HUD cover plate. This will not affect the imaging effect, reduce costs, prevent sunlight backflow, and reduce heat.

[0047] In another embodiment, optionally, the image generation unit further includes at least one reflector and a cover plate disposed on the light path emitted from the second liquid crystal cell, wherein the first polarizer is attached to the surface of the reflector or the surface of the cover plate near the second liquid crystal cell.

[0048] For example, taking two reflectors as an example, the reflectors may optionally include a first reflector and a second reflector. Both the first reflector and the second reflector are freeform surface reflectors, and their specific parameters and shapes can be designed according to the actual situation in specific implementation.

[0049] Figure 8 This is a schematic diagram of the structure of another image generation unit provided in this application. Figure 9 This is a schematic diagram of the structure of another image generation unit provided in this application. Figure 10 This is a schematic diagram of the structure of another image generation unit provided in this application, with reference to... Figures 8-10The image generation unit also includes a first reflector 51, a second reflector 52, and a cover plate 60 disposed on the light path emitted from the second liquid crystal cell 31, wherein the first polarizer 40 can be attached to the surface of the reflector or the surface of the cover plate 60 near the second liquid crystal cell 31. Figures 8-10 The diagram schematically shows the first polarizer 40 being set independently (not attached to the surface of the reflector or cover plate). In a specific implementation, a polarizing absorption film can also be set on the upper surface of the cover plate to absorb external sunlight.

[0050] Understandable Figure 8 In the embodiment, the linear polarization structure 21 is a polarizer, and its basic structure is similar to... Figure 2 The embodiments are the same, Figure 9 In the embodiment, the linear polarization structure includes a polarizing beam splitter 211 and a half-wave plate 212, and its basic structure is similar to... Figure 5 The embodiments are the same, Figure 10 In one embodiment, the linear polarization structure 21 is a polarizer, and the polarizing substrate is replaced with a brightness enhancement film, such as a dual brightness enhancement film (DBEF), which has the effect of uniform light and improved brightness.

[0051] It should be noted that the above embodiments can be combined with each other to form more embodiments.

[0052] According to this application, a display device is also provided, including any of the image generation units provided in the above embodiments.

[0053] The display device provided in this application includes any one of the image generation units provided in the above embodiments, and has the same or corresponding technical effects as the image generation unit, which will not be described in detail here.

[0054] Optionally, the display device can be a vehicle-mounted HUD display device or a general-purpose LCD display device, which can be designed according to the actual situation during implementation.

[0055] The specific embodiments described above do not constitute a limitation on the scope of protection of this application. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. An image generation unit, characterized in that, It includes a backlight module, a first liquid crystal panel, a second liquid crystal panel, and a first polarizer, which are sequentially arranged on the light-emitting side of the backlight module. The first liquid crystal panel includes a linear polarization structure, a first liquid crystal cell, and a second polarizer arranged sequentially along the light transmission direction of the backlight module; the second liquid crystal panel includes a second liquid crystal cell and a color filter arranged sequentially along the light transmission direction of the backlight module. An air gap of a preset width is provided at least at one location between the components inside the first liquid crystal panel, between the first liquid crystal panel and the second liquid crystal panel, between the components inside the second liquid crystal panel, and between the second liquid crystal panel and the first polarizer.

2. The image generation unit according to claim 1, characterized in that, The linear polarization structure includes a reflective third polarizer, which is used to modulate the emitted light from the backlight module into target linearly polarized light.

3. The image generation unit according to claim 2, characterized in that, The second polarizer is a reflective polarizer, which, in conjunction with the air gap, enhances heat dissipation.

4. The image generation unit according to claim 2, characterized in that, The linear polarization structure further includes a single-set polarizing beam splitter and a half-wave plate disposed on the side of the reflective third polarizer near the backlight module. The half-wave plate is located in the reflected light path of the polarizing beam splitter. The emitted light from the backlight module includes a first linearly polarized light and a second linearly polarized light. The first linearly polarized light is transmitted through the polarizing beam splitter to the reflective third polarizer. The second linearly polarized light is reflected by the polarizing beam splitter and transmitted through the half-wave plate, and then converted into the first linearly polarized light, which is incident on the reflective third polarizer. The polarization direction of the first linearly polarized light is parallel to the polarization direction of the target linearly polarized light, and the polarization direction of the first linearly polarized light is perpendicular to the polarization direction of the second linearly polarized light.

5. The image generation unit according to claim 1, characterized in that, The linear polarization structure includes a single set of polarizing beam splitters and a half-wave plate. The half-wave plate is located in the reflected light path of the polarizing beam splitter. The emitted light from the backlight module includes first linearly polarized light and second linearly polarized light. The first linearly polarized light is transmitted to the first liquid crystal panel through the polarizing beam splitter. The second linearly polarized light is reflected by the polarizing beam splitter and transmitted through the half-wave plate, and then converted into the first linearly polarized light, which is incident on the first liquid crystal panel. The polarization direction of the first linearly polarized light is parallel to the polarization direction of the target linearly polarized light of the first liquid crystal panel, and the polarization direction of the first linearly polarized light is perpendicular to the polarization direction of the second linearly polarized light.

6. The image generation unit according to claim 1, characterized in that, It also includes an optical functional layer located between the backlight module and the first liquid crystal panel.

7. The image generation unit according to claim 6, characterized in that, The optical functional layer includes at least one of a lens, a light-diffusing film, or a brightness-enhancing film.

8. The image generation unit according to any one of claims 1 to 7, characterized in that, It also includes at least one reflector and a cover plate disposed in the light path emitted from the second liquid crystal cell, wherein the first polarizer is attached to the surface of the reflector or the surface of the cover plate near the second liquid crystal cell.

9. The image generation unit according to claim 8, characterized in that, The reflector includes a first reflector and a second reflector.

10. The image generation unit according to claim 9, characterized in that, Both the first and second reflectors are curved reflectors.

11. The image generation unit according to claim 1, characterized in that, The resolution of the first liquid crystal panel is lower than that of the second liquid crystal panel.

12. The image generation unit according to claim 1, characterized in that, The image generation unit includes at least one of a mechanical clamp, an inlay groove, or an adhesive tape, so that at least one location is formed between the components inside the first liquid crystal panel, between the first liquid crystal panel and the second liquid crystal panel, between the components inside the second liquid crystal panel, and between the second liquid crystal panel and the first polarizer.

13. The image generation unit according to claim 12, characterized in that, The mechanical clamp, the insert groove, and the tape include openings.

14. The image generation unit according to claim 1, characterized in that, The width of the air gap is less than or equal to 10 mm.

15. The image generation unit according to claim 1, characterized in that, The first LCD panel is a monochrome LCD panel, and the second LCD panel is a color LCD panel.

16. A display device, characterized in that, Includes the image generation unit as described in any one of claims 1 to 15.

17. The display device according to claim 16, characterized in that, The display device is either a vehicle-mounted HUD display device or a general-purpose liquid crystal display device.

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