Head-up display, vehicle and control method of head-up display

Abstract

The embodiment of the invention provides a head-up display, a vehicle and a control method of the head-up display, the head-up display comprises a liquid crystal display screen and a controller, the liquid crystal display screen comprises a plurality of pixel units, each pixel unit comprises four sub-pixels W, R, G and B. The controller is connected with the liquid crystal display screen, and the controller is connected with the liquid crystal display screen. The controller is configured to drive W sub-pixels in the liquid crystal display screen so as to adjust the transmittance of the liquid crystal display screen.

Description

Technical Field

[0001] The present disclosure relates to the field of display technology, and in particular to a head-up display, a vehicle, and a control method for the head-up display. Background Art

[0002] HUD (head up di Splay) is also called a head-up display. By projecting the light emitted by the HUD image source onto an imaging window (such as a rear-mounted imaging board or a vehicle's windshield, etc.), users can directly see the picture without lowering their heads, avoiding distractions caused by the driver looking down at the dashboard during driving, thereby improving driving safety and user driving experience.

[0003] The image source of the HUD can be a liquid crystal display, which includes a TFT liquid crystal display and a backlight module. The backlight module is used to provide backlight for the TFT liquid crystal display so that the TFT liquid crystal display can display images to emit image light. The TFT liquid crystal display includes a color filter film (CF). The main structure of the color filter film includes red sub-pixels (R), green sub-pixels (G), and blue sub-pixels (B). The function of the R, G, and B sub-pixels is to selectively transmit the required colors, thereby filtering the light source light (white light) emitted by the backlight module into colorful colored light. However, the light transmittance of this liquid crystal display is low, which results in a low brightness of the virtual image formed by the HUD. Summary of the invention

[0004] The purpose of the embodiments of the present disclosure is to provide a head-up display, a vehicle and a control method for a head-up display, so as to solve the technical problem in the prior art that the light transmittance of a liquid crystal display screen is relatively low, resulting in low brightness of a virtual image formed by the HUD.

[0005] In order to solve the above technical problems, the embodiments of the present disclosure adopt the following technical solutions:

[0006] The embodiment of the present disclosure provides a head-up display, including a liquid crystal display screen and a controller, wherein the liquid crystal display screen includes a plurality of pixel units, each of which includes four sub-pixels of W, R, G, and B, wherein:

[0007] The controller is connected to the liquid crystal display screen, and is configured to drive the W sub-pixel in the liquid crystal display screen to adjust the transmittance of the liquid crystal display screen.

[0008] In some embodiments, in each of the pixel units, the proportion of the area occupied by the W sub-pixel in the pixel unit is greater than or equal to 1 / 5 and less than or equal to 4 / 5.

[0009] In some embodiments, the controller is configured to drive the W sub-pixel in the liquid crystal display to adjust the transmittance of the liquid crystal display, including:

[0010] When the head-up display is in the first mode, the controller is configured to drive the W sub-pixel in the liquid crystal display screen according to the ambient light brightness of the ambient space corresponding to the virtual image formed by the head-up display screen to adjust the transmittance of the liquid crystal display screen.

[0011] In some embodiments, the controller is configured to drive the W sub-pixel in the liquid crystal display screen according to the ambient light brightness of the ambient space corresponding to the virtual image formed by the head-up display, including:

[0012] If the ambient light brightness is greater than a first preset brightness threshold, the controller is configured to drive the W sub-pixel to emit light to increase the transmittance of the liquid crystal display;

[0013] If the ambient light brightness is less than or equal to the first preset brightness threshold, the controller is configured not to drive the W sub-pixel to emit light.

[0014] In some embodiments, the controller is configured to drive the W sub-pixel in the liquid crystal display to adjust the transmittance of the liquid crystal display, including:

[0015] When the head-up display is in the first mode, the controller is configured to adjust the grayscale value of the W sub-pixel according to a preset correspondence between the ambient light brightness corresponding to the head-up display and the grayscale value of the W sub-pixel, wherein the ambient light brightness corresponding to the head-up display is the ambient light brightness of the ambient space corresponding to the virtual image formed by the head-up display, and the grayscale value of the W sub-pixel increases with the increase of the ambient light brightness.

[0016] In some embodiments, the controller is configured to drive the W sub-pixel in the liquid crystal display to adjust the transmittance of the liquid crystal display, including:

[0017] When the head-up display is in the second mode, the controller is configured to drive the W sub-pixel in each pixel unit in the liquid crystal display screen according to the grayscale values ​​of the three sub-pixels R, G, and B in each pixel unit to improve the transmittance of the liquid crystal display screen.

[0018] In some embodiments, the controller is configured to:

[0019] Determine the grayscale value of the W sub-pixel according to the grayscale values ​​of the three sub-pixels R, G, and B in each of the pixel units;

[0020] The grayscale values ​​of the three R, G, and B sub-pixels are updated according to the adjusted grayscale value of the W sub-pixel.

[0021] In some embodiments, the head-up display further includes a backlight module for providing backlight for the liquid crystal display screen, the controller is connected to the backlight module, and the controller is configured to control the backlight module to emit light.

[0022] In some embodiments, the backlight module excites yellow phosphors through a blue chip to emit white light; or

[0023] The backlight module excites red and green phosphors through a blue chip to emit white light; or

[0024] The backlight module emits red, green and blue light respectively through red, green and blue chips, and the red, green and blue light are mixed to emit white light.

[0025] In some embodiments, the controller is configured to:

[0026] Determining the transmittance of the liquid crystal display screen and determining a preset brightness corresponding to the virtual image formed by the head-up display;

[0027] Determining the backlight brightness of the liquid crystal display screen according to the transmittance of the liquid crystal display screen and the preset brightness corresponding to the virtual image;

[0028] The light emitting brightness of the backlight module is adjusted according to the backlight brightness of the liquid crystal display screen.

[0029] In some embodiments, the controller is further configured to compensate for the grayscale value of at least one of the three R, G, and B sub-pixels after adjusting the luminous brightness of the backlight module according to the backlight brightness of the liquid crystal display.

[0030] In some embodiments, the backlight spectrum distribution of the backlight module corresponds to the light transmission spectrum distribution of the liquid crystal display.

[0031] In some embodiments, the controller is further configured to:

[0032] Capturing an image of the environment in front of the vehicle by an image acquisition device disposed on the vehicle;

[0033] The ambient light brightness of the ambient space corresponding to the virtual image formed by the head-up display is determined according to the brightness of the ambient image.

[0034] In some embodiments, the head-up display further includes a backlight module for providing backlight for the liquid crystal display screen, the backlight module includes a plurality of light source elements, and the controller is further configured to:

[0035] Dividing the display area of ​​the liquid crystal display screen into a plurality of sub-areas, and determining a corresponding relationship between each sub-area and a light source element in the backlight module that provides backlight for the sub-area;

[0036] In a case where the image to be displayed on the liquid crystal display screen includes target picture content, determining a target sub-region covered by the target picture content and other sub-regions in the display region except the target sub-region;

[0037] When the ambient light brightness is less than or equal to the first preset brightness threshold, the W sub-pixels in the target sub-region are driven to emit light, and the W sub-pixels in the other sub-regions are not driven to emit light.

[0038] In some embodiments, the transmittance of the R color resist in each of the pixel units within the wavelength range of 400nm-580nm is less than 10%; the transmittance of the G color resist in each of the pixel units within the wavelength range of 430nm-450nm is less than 5%, and the transmittance in the wavelength range of 600nm-700nm is less than 5%; the transmittance of the B color resist in each of the pixel units within the wavelength range of 500nm-700nm is less than 10%.

[0039] The disclosed embodiment also provides a vehicle, comprising the above-mentioned head-up display.

[0040] The present disclosure also provides a method for controlling a head-up display, wherein the head-up display includes a liquid crystal display screen, the liquid crystal display screen includes a plurality of pixel units, each of the pixel units includes four sub-pixels of W, R, G, and B, and the method includes:

[0041] The W sub-pixel in the liquid crystal display is driven to adjust the transmittance of the liquid crystal display.

[0042] In some embodiments, driving the W sub-pixel in the liquid crystal display screen to adjust the transmittance of the liquid crystal display screen includes:

[0043] When the head-up display is in the first mode, the W sub-pixel in the liquid crystal display is driven according to the ambient light brightness of the ambient space corresponding to the virtual image formed by the head-up display to adjust the transmittance of the liquid crystal display.

[0044] In some embodiments, driving the W sub-pixel in the liquid crystal display screen according to the ambient light brightness of the ambient space corresponding to the virtual image formed by the head-up display includes:

[0045] If the ambient light brightness is greater than a first preset brightness threshold, driving the W sub-pixel to emit light to increase the transmittance of the liquid crystal display;

[0046] If the ambient light brightness is less than or equal to the first preset brightness threshold, the W sub-pixel is not driven to emit light.

[0047] In some embodiments, driving the W sub-pixel in the liquid crystal display screen to adjust the transmittance of the liquid crystal display screen includes:

[0048] When the head-up display is in the second mode, the W sub-pixel in each pixel unit in the liquid crystal display is driven according to the grayscale values ​​of the three sub-pixels R, G, and B in each pixel unit to improve the transmittance of the liquid crystal display.

[0049] In some embodiments, the head-up display further includes a backlight module for providing backlight for the liquid crystal display screen, and the method further includes: controlling the backlight module to emit light.

[0050] In some embodiments, controlling the backlight module to emit light includes:

[0051] Determining the transmittance of the liquid crystal display screen and determining a preset brightness corresponding to the virtual image formed by the head-up display;

[0052] Determining the backlight brightness of the liquid crystal display screen according to the transmittance of the liquid crystal display screen and the preset brightness corresponding to the virtual image;

[0053] The light emitting brightness of the backlight module is adjusted according to the backlight brightness of the liquid crystal display screen.

[0054] The head-up display, vehicle and control method of the head-up display provided in the embodiments of the present disclosure are configured by setting a liquid crystal display and a controller connected to the liquid crystal display, wherein the liquid crystal display includes a plurality of pixel units, each pixel unit includes four sub-pixels of W, R, G, and B, and the controller is configured to drive the W sub-pixel in the liquid crystal display to adjust the transmittance of the liquid crystal display, thereby adjusting the display brightness of the virtual image formed by the head-up display, thereby improving the user's HUD usage experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in 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 recorded in the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0056] Figure 1 It is a schematic diagram of the structure of a head-up display according to an embodiment of the present disclosure;

[0057] Figure 2 is a schematic diagram of the arrangement of sub-pixels in a single pixel unit according to an embodiment of the present disclosure;

[0058] Figure 3 is a schematic diagram of the arrangement of sub-pixels in another single pixel unit according to an embodiment of the present disclosure;

[0059] Figure 4 is a schematic diagram of the arrangement of sub-pixels in another single pixel unit according to an embodiment of the present disclosure;

[0060] Figure 5 FIG. 4 is a schematic diagram of the arrangement of multiple pixel units according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0061] Various aspects and features of the present disclosure are described herein with reference to the drawings.

[0062] It should be understood that various modifications may be made to the embodiments of the present application. Therefore, the above description should not be considered as limiting, but only as an example of an embodiment. Other modifications within the scope and spirit of the present disclosure will occur to those skilled in the art.

[0063] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the present disclosure and, together with the general description of the present disclosure given above and the detailed description of the embodiments given below, serve to explain the principles of the present disclosure.

[0064] These and other characteristics of the present disclosure will become apparent from the following description of a preferred form of embodiment given as a non-limiting example, with reference to the attached drawings.

[0065] It should also be understood that, although the present disclosure has been described with reference to some specific examples, those skilled in the art will be able to realize many other equivalent forms of the present disclosure that have the features described in the claims and are therefore within the scope of protection defined thereby.

[0066] The above and other aspects, features and advantages of the present disclosure will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

[0067] Specific embodiments of the present disclosure are described hereinafter with reference to the accompanying drawings; however, it should be understood that the embodiments claimed are merely examples of the present disclosure, which may be implemented in a variety of ways. Well-known and / or repeated functions and structures are not described in detail to avoid obscuring the present disclosure with unnecessary or redundant details. Therefore, the specific structural and functional details claimed herein are not intended to be limiting, but merely serve as a basis and representative basis for the claims to teach those skilled in the art to use the present disclosure in a variety of ways with substantially any suitable detailed structure.

[0068] This specification may use the phrases "in one embodiment," "in another embodiment," "in a further embodiment," or "in other embodiments," all of which may refer to one or more of the same or different embodiments according to the present disclosure.

[0069] Figure 1 A schematic diagram of the structure of a head-up display according to an embodiment of the present disclosure is shown. Figures 2 to 4 A schematic diagram of a single pixel unit according to an embodiment of the present disclosure is shown. Figure 5 FIG. 2 shows a schematic diagram of multiple pixel units according to an embodiment of the present disclosure. Figures 1 to 5 As shown, the first embodiment of the disclosed embodiment provides a head-up display 10, including a liquid crystal display 101 and a controller 102. The liquid crystal display 101 may be a thin film transistor liquid crystal display (TFT-LCD), which includes a plurality of pixel units, each of which includes four sub-pixels of W (white), R (red), G (green), and B (blue), wherein the controller 102 is connected to the liquid crystal display 101, and the controller 102 is configured to drive the W sub-pixel in the liquid crystal display 101 to adjust the transmittance of the liquid crystal display 101. In some embodiments, the controller 102 may be a driving circuit.

[0070] The controller 102 can transmit the grayscale voltage to the electrode of each sub-pixel through the data line, so that each sub-pixel displays the corresponding grayscale value, thereby displaying the picture on the liquid crystal display screen 101. Specifically, the multiple pixel units of the liquid crystal display screen 101 are arranged in an array, and the controller 102 is connected to each sub-pixel in each pixel unit in a one-to-one correspondence to provide a driving signal to the corresponding sub-pixel to realize the display of the display picture on the liquid crystal display screen 101. When the display picture is displayed on the liquid crystal display screen 101, the liquid crystal display screen 101, as an image source of the head-up display, emits image light, and the image light can be incident on the amplifying element, and after being processed by the amplifying element, it is incident on the windshield, and the windshield 20, an external reflection device, is used to reflect the image light to the human eye to form a virtual image, and the virtual image formed can be projected near the windshield 20 or in front of the windshield 20 for the user to view.

[0071] In some embodiments, the magnifying element, such as a curved reflector, an optical waveguide or a holographic optical element (HOE), is used to magnify the display screen displayed by the image source. When the image source is a curved reflector, the image light emitted by the image source is reflected by the curved reflector to the windshield of the vehicle, and reaches the eye box area after being reflected by the windshield. When the user's eyes are located in the eye box area, the user can see the virtual image formed in front of the windshield.

[0072] The transmittance of the liquid crystal display screen 101 refers to the light transmittance of the liquid crystal display screen 101. For the light source light emitted by the light source in the backlight module, the R, G, and B sub-pixels in the liquid crystal display screen can only transmit the light source light of a specific wavelength band, while the W sub-pixel does not select the transmission wavelength band, so the transmittance of the liquid crystal display screen 101 is higher than that of the RGB three-primary color liquid crystal display screen. Furthermore, in this embodiment, by adding a W sub-pixel to each pixel unit and driving the sub-pixel through the controller 102, the transmittance of the liquid crystal display screen 101 can be adjusted according to the environmental information around the liquid crystal display screen 101, so that the brightness of the image displayed in the liquid crystal display screen 101 can be adjusted, and then the brightness of the image light emitted by the liquid crystal display screen 101 can be adjusted, and the brightness of the virtual image formed by the head-up display 10 can be adjusted. For example, when the transmittance of the liquid crystal display screen 101 is improved by driving the W sub-pixel to emit light, the brightness of the virtual image can be improved under the condition that the power consumption of the backlight module of the liquid crystal display screen 101 is the same (that is, the backlight brightness is the same), so that the user can see the virtual image more clearly, or, for example, when the display mode of the head-up display is the instrument mode, the content displayed in the virtual image is various instrument information, and at this time, the power consumption of the backlight module can be appropriately reduced, so as to improve the brightness of the virtual image while reducing the heat of the liquid crystal display screen caused by the backlight power consumption, or reduce the power consumption of the backlight module to maintain the brightness of the virtual image at a preset brightness, so as to avoid the damage to the human eye caused by the excessive brightness of the virtual image and the waste of backlight power consumption.

[0073] The head-up display 10 provided in the embodiment of the present disclosure is provided with a liquid crystal display screen 101 and a controller 102 connected to the liquid crystal display screen 101. The liquid crystal display screen 101 includes a plurality of pixel units, each of which includes four sub-pixels of W, R, G, and B. The controller 102 is configured to drive the W sub-pixel in the liquid crystal display screen 101 to adjust the transmittance of the liquid crystal display screen 101, thereby adjusting the display brightness of the virtual image formed by the head-up display, and improving the user's HUD usage experience. For example, the W sub-pixel in the liquid crystal display screen 101 is driven to emit light, thereby improving the transmittance of the liquid crystal display screen 101, and then the display brightness of the virtual image formed by the head-up display can be improved, so that the user can view the content displayed in the virtual image more conveniently.

[0074] In some embodiments, in each pixel unit, the proportion of the area of ​​the pixel unit occupied by the W sub-pixel is greater than or equal to 1 / 5 and less than or equal to 4 / 5.

[0075] Specifically, Figures 2 to 4 As shown, the arrangement of the four sub-pixels W, R, G, and B can be a single row arrangement or a multi-row arrangement, and the shape of the sub-pixels can be any shape. For example, Figure 2 In the figure, the W sub-pixel is located below the R, G, and B sub-pixels; Figure 3 In the example, R, G, B, and W sub-pixels are arranged in the same row, and the shapes of the R, G, B, and W sub-pixels are rectangular; Figure 4 In the embodiment, the R, G, B, and W sub-pixels are arranged in the same row, and the shapes of the R, G, B, and W sub-pixels are parallelograms.

[0076] In each pixel unit, the area ratio of the W sub-pixel to the entire pixel unit is greater than or equal to 1 / 5 (for example, greater than 1 / 4). The larger the area of ​​the W sub-pixel is, the more the transmittance of the liquid crystal display screen 101 will be improved after the W sub-pixel is driven to emit light; the area ratio of the W sub-pixel to the entire pixel unit is less than or equal to 4 / 5 (for example, less than 2 / 3) to avoid the W sub-pixel occupying too large a proportion, causing problems such as color imbalance and affecting the imaging quality of the virtual image.

[0077] Optionally, in this embodiment, the area of ​​the W sub-pixel may be set larger (ie, the area of ​​the W sub-pixel is the largest among the four sub-pixels) to further improve the transmittance of the liquid crystal display screen 101, thereby improving the brightness of the virtual image.

[0078] In some embodiments, the controller 102 is configured to drive the W sub-pixel in the liquid crystal display screen 101 to adjust the transmittance of the liquid crystal display screen 101, including:

[0079] When the head-up display 10 is in the first mode, the controller 102 is configured to drive the W sub-pixel in the LCD screen 101 according to the ambient light brightness of the ambient space corresponding to the virtual image formed by the head-up display 10 to adjust the transmittance of the LCD screen 101 .

[0080] Specifically, the first mode refers to a working mode in which the W sub-pixel is conditionally driven. The ambient light brightness of the environment space corresponding to the virtual image formed by the head-up display 10 refers to the light intensity of the environment space. For example, when the vehicle is driving in the daytime, due to the strong reflection of the white car driving in front, the ambient light brightness in front of the vehicle's field of view is brighter, and the virtual image of the virtual image may not be easily observed or recognized by the user. Therefore, the W sub-pixel can be driven to emit light to increase the transmittance of the liquid crystal display screen, thereby increasing the brightness of the virtual image; and when the vehicle is driving at night, the ambient light brightness is darker, and the brightness contrast between the darker ambient light and the virtual image is obvious. At this time, it is not necessary to increase the brightness of the virtual image by driving the W sub-pixel to emit light. Not driving the W sub-pixel to emit light can also maintain the color gamut of the liquid crystal display screen and ensure the color display effect of the virtual image. For example, when playing movies, videos and other multimedia content through the head-up display at night, the content displayed in the virtual image includes movie and video pictures. At this time, not driving the W sub-pixel to emit light can ensure the color display effect of the movie and video pictures in the virtual image, avoiding the problem of color display imbalance.

[0081] In order to make the brightness of the virtual image adapt to the light intensity of the ambient space so that the user can see the virtual image clearly or ensure the color display effect of the virtual image, in this embodiment, when the head-up display 10 is in the first mode, the controller 102 can drive the W sub-pixel according to the ambient light brightness of the ambient space corresponding to the virtual image formed by the head-up display, and adjust the transmittance of the liquid crystal display 101 to meet the display requirements of the virtual image under different ambient light intensities.

[0082] Further, the controller 102 is configured to drive the W sub-pixel in the liquid crystal display screen 101 according to the ambient light brightness of the ambient space corresponding to the virtual image formed by the head-up display 10, including:

[0083] If the ambient light brightness is greater than the first preset brightness threshold, the controller 102 is configured to drive the W sub-pixel to emit light to increase the transmittance of the liquid crystal display 101;

[0084] If the ambient light brightness is less than or equal to the first preset brightness threshold, the controller 102 is configured not to drive the W sub-pixel to emit light.

[0085] When the ambient light brightness is brighter than the first preset brightness threshold, the controller 102 drives the W sub-pixel to emit light, that is, controls the W sub-pixel to start working, so as to improve the transmittance of the liquid crystal display screen 101, and can improve the brightness of the virtual image formed by the head-up display 10, so as to facilitate the user to clearly observe the virtual image content of the virtual image, such as navigation instructions, vehicle speed and other information.

[0086] When the ambient light brightness is less than or equal to the first preset brightness threshold, the controller 102 does not drive the W sub-pixel to emit light, that is, controls the W sub-pixel to turn off, which can ensure the color gamut range of the virtual image and ensure that the user can still observe the virtual image with a high color gamut when the ambient light brightness is low. The size of the color gamut represents the color range that the liquid crystal display screen 101 can display. The larger the color gamut range, the more types of colors that the liquid crystal display screen 101 can display, and the corresponding virtual image is brighter. The size of the color gamut can be a color gamut percentage (such as the NTSC standard) to describe the color reproduction ability of the display. NTSC is defined as the ratio of the area of ​​a triangle composed of three primary colors to the area of ​​a triangle composed of three primary colors of the standard NTSC under the CIE1931XYZ coordinates.

[0087] When the controller 102 drives the W sub-pixel to emit light, the color gamut range of the liquid crystal display screen 101 will be reduced, thereby causing the color gamut range of the virtual image to be reduced. Therefore, in this embodiment, when the ambient light brightness is dark, the controller 102 does not drive the W sub-pixel to emit light, that is, controls the W sub-pixel not to work, so as to maintain the color gamut range of the virtual image. In a specific implementation, the controller 102 can set the grayscale value of the W sub-pixel to 0 (completely black) and does not drive the W sub-pixel to emit light. In some embodiments, the controller 102 does not drive the W sub-pixel to emit light, including: the controller 102 transmits a grayscale voltage corresponding to a zero grayscale value to the W sub-pixel through a data line, so that the W sub-pixel does not emit light (that is, the light emitted by the backlight module cannot pass through the filter corresponding to the W sub-pixel, so that the W sub-pixel does not emit light).

[0088] In some embodiments, the head-up display 10 further includes a backlight module for providing backlight for the liquid crystal display screen 101, and the controller 102 is connected to the backlight module, and the controller 102 is configured to control the backlight module to emit light. The backlight module may include a plurality of light source elements, and the light source elements are used to emit light source light, and the light source light is incident on the liquid crystal display screen 101, and is converted into image light by the liquid crystal display screen 101 and then emitted.

[0089] The controller 102 can control the backlight module to emit light and drive the R, G, B, and W sub-pixels of the liquid crystal display screen 101 to emit light. The light source light (white light) emitted by the backlight module can be filtered into R, G, and B colored light by the R, G, and B sub-pixels, and mixed to form colorful colored light. Through the high transmittance of the W sub-pixel, the transmittance of the liquid crystal display screen 101 can be increased without changing the backlight brightness, and the brightness of the virtual image can be increased, which is convenient for users to watch. The light source element in the backlight module can be an LED (Light Emitting Diode) light emitting element.

[0090] Exemplarily, when the ambient light is bright, the ambient light incident on the liquid crystal display screen 101 will cause the liquid crystal display screen 101 to heat up, and the high power consumption of the backlight module will also cause the liquid crystal display screen 101 to heat up. In order to extend the life of the liquid crystal display screen 101 or prevent the liquid crystal display screen 101 from being burned, the backlight of the head-up display 10 will only be turned on to a certain brightness value. At this time, the virtual image of the virtual image may not be easily observed or recognized by the user. Therefore, in this embodiment, the transmittance of the liquid crystal display screen 101 is increased by driving the W sub-pixel by the controller 102, and the brightness of the virtual image can be increased while the backlight brightness (backlight power consumption) remains unchanged, so as to facilitate the user to watch. When the ambient light is dark, it is not necessary to increase the brightness of the virtual image, and only the brightness of the display screen on the liquid crystal display screen 101 can be kept unchanged. At this time, the backlight brightness of the backlight module can be reduced, thereby reducing the backlight power consumption, and keeping the brightness and color of the virtual image unchanged, that is, under the premise of meeting the brightness and color requirements of the virtual image, the backlight power consumption is reduced, and the service life of the head-up display 10 is extended.

[0091] In some embodiments, the head-up display 10 also includes a backlight module for providing backlight for the liquid crystal display screen 101, the backlight module includes multiple light source elements, and the controller 102 is further configured to: divide the display area of ​​the liquid crystal display screen 101 into multiple sub-areas, and determine the correspondence between each sub-area and the light source element in the backlight module that provides backlight for the sub-area, wherein each sub-area corresponds one-to-one to each light source element; when the image to be displayed on the liquid crystal display screen 101 includes target picture content, determine the target sub-area covered by the target picture content, and other sub-areas in the display area except the target sub-area; when the ambient light brightness is less than or equal to a first preset brightness threshold, drive the W sub-pixels located in the target sub-area to emit light, and do not drive the W sub-pixels located in other sub-areas to emit light.

[0092] Among them, when the ambient light brightness is less than or equal to the first preset brightness threshold, for example, at night, when the image to be displayed on the LCD screen 101 contains target screen content (such as electronic rearview mirror image, reversing image and other screen content), the target sub-area covered by the target screen content can be determined, that is, when the LCD screen displays the image to be displayed, the target screen content is displayed in the target sub-area. The target sub-area can be multiple sub-areas, for example, the electronic rearview mirror image is displayed in sub-area 1 to sub-area 4, and each sub-area in sub-area 1 to sub-area 4 displays part of the content in the electronic rearview mirror image. In order to increase the display brightness of the target screen content, the W sub-pixel located in the target sub-area can be driven to emit light, so as to facilitate the user to watch the target screen content. The W sub-pixel in the target sub-region is driven to emit light, for example, the grayscale value of each W sub-pixel in the target sub-region may be set to a default grayscale value; or the grayscale value of the W sub-pixel may be determined according to the grayscale values ​​of the three R, G, and B sub-pixels in the pixel unit where each W sub-pixel is located, for example, the grayscale value of the W sub-pixel may be determined according to the minimum grayscale value of the three R, G, and B sub-pixels, wherein the W sub-pixel may be the minimum value of the grayscale values ​​of the three R, G, and B sub-pixels or other values ​​less than the minimum value.

[0093] In some embodiments, the controller 102 is configured to drive the W sub-pixel in the liquid crystal display screen 101 to adjust the transmittance of the liquid crystal display screen 101, including:

[0094] When the head-up display 10 is in the first mode, the controller 102 is configured to adjust the grayscale value of the W sub-pixel according to a preset correspondence between the ambient light brightness corresponding to the head-up display 10 and the grayscale value of the W sub-pixel, wherein the ambient light brightness corresponding to the head-up display 10 is the ambient light brightness of the ambient space corresponding to the virtual image formed by the head-up display 10, and the grayscale value of the W sub-pixel increases with the increase of the ambient light brightness.

[0095] In some embodiments, after the grayscale value of the W sub-pixel is determined according to the preset correspondence between the ambient light brightness corresponding to the head-up display 10 and the grayscale value of the W sub-pixel, the liquid crystal display drives each pixel row in a row-by-row scanning manner, and the controller 102 transmits the grayscale voltages corresponding to the respective grayscale values ​​to the W, R, G, and B sub-pixels in the pixel row through the data lines, thereby driving the W, R, G, and B sub-pixels to emit light, wherein the grayscale values ​​of the R, G, and B sub-pixels (i.e., the original grayscale values, or referred to as the target grayscale values) can be determined according to the video / image signals transmitted by the signal source of the liquid crystal display.

[0096] During the driving process of the vehicle, the brightness of the ambient light in front of the vehicle's field of view can be detected by an image acquisition device or a light sensor set in the vehicle, and sent to the controller 102. When the head-up display 10 is in the first mode, the controller 102 can adjust the grayscale value of the W sub-pixel according to the detected ambient light brightness and the preset correspondence between the ambient light brightness and the grayscale value of the W sub-pixel, so as to adjust the transmittance of the liquid crystal display screen 101 so that the ambient light brightness matches the brightness of the virtual image. The grayscale value of the W sub-pixel can be adjusted between 0 and 255, wherein grayscale 0 is completely black, and the W sub-pixel does not emit light (that is, the light incident on the W sub-pixel cannot pass through the W sub-pixel), and grayscale 255 is completely white, and the W sub-pixel emits light and has the maximum brightness (that is, the light incident on the W sub-pixel can all pass through the W sub-pixel), thereby improving the transmittance of the liquid crystal display screen 101.

[0097] In this embodiment, the grayscale value of the W sub-pixel increases with the increase of the ambient light brightness, that is, the transmittance of the liquid crystal display screen 101 increases with the increase of the ambient light brightness, thereby increasing the brightness of the virtual image.

[0098] It is understandable that when the controller 102 adjusts the grayscale value of the W sub-pixel, the grayscale values ​​of the R, G, and B sub-pixels can be controlled to remain unchanged. For example, in a certain pixel unit in the liquid crystal display screen 101, the original grayscale values ​​of the R, G, and B sub-pixels are (100, 150, 200), and after the W sub-pixel is adjusted, the grayscale values ​​of the R, G, B, and W sub-pixels are (100, 150, 200, 50). In each pixel unit, the original grayscale values ​​(or target grayscale values) of the R, G, and B sub-pixels can be determined according to the video / image signal transmitted by the signal source of the liquid crystal display screen.

[0099] When the LCD screen is scanned and driven, the controller 102 transmits the grayscale voltage corresponding to the target grayscale value to the R, G, and B sub-pixels in each pixel unit in turn, and transmits the grayscale voltage corresponding to the grayscale value to the W sub-pixel, so that the LCD screen displays the video / image transmitted by the signal source.

[0100] The preset corresponding relationship between the ambient light brightness corresponding to the head-up display 10 and the grayscale value of the W sub-pixel can be predetermined according to actual needs. For example, different W sub-pixel grayscale values ​​can be configured for different ambient light brightness ranges (the ambient light brightness range and the grayscale value of the W sub-pixel are in a discrete relationship), and the ambient light brightness and the grayscale value of the W sub-pixel can also be in a linear relationship or a non-linear relationship (such as a curve relationship), etc., and the present disclosure is not limited to this.

[0101] It can be understood that, in the present embodiment, the controller 102 drives the W sub-pixel to emit light or does not drive the W sub-pixel to emit light by adjusting the grayscale value of the W sub-pixel. When the grayscale value of the W sub-pixel is 0, the controller 102 does not drive the W sub-pixel to emit light. When the grayscale value of the W sub-pixel is any value between (0, 255], the controller 102 drives the W sub-pixel to emit light, and the light luminance of the W sub-pixel is adjusted as the brightness of the ambient light changes.

[0102] In some embodiments, the controller 102 is further configured to:

[0103] Capturing an image of the environment in front of the vehicle by an image acquisition device disposed on the vehicle;

[0104] The ambient light brightness of the ambient space corresponding to the virtual image formed by the head-up display 10 is determined according to the brightness of the ambient image.

[0105] Specifically, an image acquisition device is provided on the vehicle to acquire an environmental image in front of the vehicle, and the brightness of the ambient light in front of the field of view of the vehicle can be obtained by analyzing the brightness of the environmental image. For example, the brightness of the environmental image is obtained by analyzing the environmental image acquired by the image acquisition device, and then the brightness of the ambient light corresponding to the brightness of the environmental image is calculated by the corresponding relationship between the brightness of the environmental image and the brightness of the ambient light; or the brightness of the environmental image is divided by the exposure time to obtain the ambient light brightness, so as to accurately determine the ambient light brightness of the environmental space corresponding to the virtual image formed by the head-up display 10.

[0106] In some embodiments, the controller 102 is configured to drive the W sub-pixel in the liquid crystal display screen 101 to adjust the transmittance of the liquid crystal display screen 101, including:

[0107] When the head-up display 10 is in the second mode, the controller 102 is configured to drive the W sub-pixel in each pixel unit in the LCD screen 101 according to the grayscale values ​​of the three sub-pixels R, G, and B in each pixel unit to improve the transmittance of the LCD screen 101.

[0108] The second mode includes a working mode in which the W sub-pixel is always on, in which the W sub-pixel is always emitting light. In this embodiment, when the controller 102 drives the W sub-pixel in a certain pixel unit to emit light, the target grayscale value to be adjusted for the W sub-pixel can be determined according to the grayscale values ​​of the three R, G, and B sub-pixels in the pixel unit (i.e., the original grayscale values ​​of the three R, G, and B sub-pixels), and then the grayscale value of the W sub-pixel is adjusted according to the target grayscale value, thereby improving the transmittance of the liquid crystal display screen 101 and the brightness of the virtual image.

[0109] In some embodiments, the controller 102 is configured to drive the W sub-pixel in each pixel unit of the liquid crystal display screen 101 according to the grayscale values ​​of the three sub-pixels R, G, and B in each pixel unit to improve the transmittance of the liquid crystal display screen 101, including:

[0110] Determine the grayscale value of the W sub-pixel according to the grayscale values ​​of the three sub-pixels R, G, and B in each pixel unit;

[0111] The grayscale values ​​of the three sub-pixels R, G, and B are updated according to the adjusted grayscale value of the W sub-pixel.

[0112] When the W sub-pixel in a pixel unit in the liquid crystal display screen 101 is driven to emit light according to the grayscale values ​​of the three sub-pixels R, G, and B in a certain pixel unit, the grayscale value of the W sub-pixel can be determined according to the minimum grayscale value of the three sub-pixels R, G, and B, wherein the W sub-pixel can be the minimum value of the grayscale values ​​of the three sub-pixels R, G, and B or other values ​​less than the minimum value. For example, the grayscale values ​​of the three sub-pixels R, G, and B in a certain pixel unit are (100, 150, 200) respectively, and the grayscale value of the W sub-pixel can be the minimum value 100 therein. After adjusting the grayscale value of the W sub-pixel according to the grayscale value, the grayscale values ​​of the three sub-pixels R, G, and B can be updated to ensure the overall display effect of the virtual image. For example, the original grayscale values ​​of the R, G, and B sub-pixels are subtracted from the grayscale value of the W sub-pixel, and the updated grayscale values ​​of the R, G, and B sub-pixels can be (0, 50, 100).

[0113] In some embodiments, the backlight module excites yellow phosphors through a blue chip to emit white light; or

[0114] The backlight module excites the red and green phosphors to emit white light through the blue chip; or

[0115] The backlight module emits red, green and blue light respectively through red, green and blue chips, and the red, green and blue light are mixed to emit white light.

[0116] The backlight module can emit white light through the above-mentioned chips of different colors to provide backlight for the liquid crystal display 101. The backlight module uses a blue light chip as a basis and converts blue light into white light by coating or encapsulating fluorescent materials. For example, a blue light chip excites yellow phosphor to make a white light LED, which is convenient to emit light and has low cost. As mentioned above, after the controller 102 drives the W sub-pixel, the color gamut of the liquid crystal display 101 will be reduced. Therefore, in order to ensure that the color gamut will not be reduced too much, in this embodiment, the backlight module uses a blue chip to excite red and green phosphors to emit white light, or the backlight module uses red, green, and blue chips to emit light separately, that is, red, green, and blue light are respectively emitted and mixed to obtain white light.

[0117] In some embodiments, the controller 102 is configured to:

[0118] Determining the transmittance of the liquid crystal display screen 101 and determining a preset brightness corresponding to the virtual image formed by the head-up display 10;

[0119] Determining the backlight brightness of the liquid crystal display screen 101 according to the transmittance of the liquid crystal display screen 101 and the preset brightness corresponding to the virtual image;

[0120] The light emitting brightness of the backlight module is adjusted according to the backlight brightness of the liquid crystal display screen 101 .

[0121] Specifically, the controller 102 can calculate the transmittance of the liquid crystal display screen 101 according to the grayscale values ​​of the R, G, B, and W sub-pixels of all pixel units in the current liquid crystal display screen 101; or, by detecting the current screen brightness of the liquid crystal display screen and the luminous brightness of the backlight source, calculate the current transmittance of the liquid crystal display screen. Then, according to the preset brightness value corresponding to the virtual image formed by the head-up display 10 and the calculated transmittance of the liquid crystal display screen 101, the backlight brightness value of the liquid crystal display screen 101 at this time is calculated. The backlight brightness value of the liquid crystal display screen 101 is obtained by substituting the preset brightness value corresponding to the virtual image formed by the head-up display 10 and the transmittance of the liquid crystal display screen 101 according to the formula: liquid crystal display screen brightness = backlight brightness * liquid crystal display transmittance. After determining the backlight brightness of the liquid crystal display screen 101, the luminous brightness of the backlight module can be controlled according to the backlight brightness to reduce the backlight power consumption. For example, in this embodiment, after adjusting the grayscale values ​​of the R, G, and B sub-pixels according to the grayscale value of the W sub-pixel, the transmittance of the adjusted LCD display 101 is determined, and then the luminous brightness of the optical module is adjusted to reduce backlight power consumption.

[0122] In some embodiments, the controller 102 is further configured to compensate the grayscale value of at least one of the three R, G, and B sub-pixels after adjusting the light emitting brightness of the backlight module according to the backlight brightness of the liquid crystal display 101 .

[0123] After reducing the backlight power consumption (i.e., adjusting the backlight brightness of the backlight module), the reduction in backlight brightness will cause a loss in the display brightness of the sub-pixels with non-zero grayscale in the R, G, and B sub-pixels. For example, when the grayscale value of the W sub-pixel is determined to be 100 and the updated grayscale values ​​of the R, G, and B sub-pixels are calculated to be (0, 50, 100), the backlight brightness is reduced (for example, reduced to 50 cd / m 2 ) will cause the display brightness of the G and B sub-pixels to fall short of the original backlight brightness (e.g. 70 cd / m 2) case, the display brightness of the G and B sub-pixels with grayscales of 50 and 100 respectively, therefore, after reducing the backlight power consumption, it is necessary to compensate the grayscale values ​​of the G and B sub-pixels to a certain extent (i.e., increase the grayscale values ​​of the G and B sub-pixels), so as to ensure that after the compensated R, G, B, W are converted into RGB, the ratio of each R, G, B component is the same as the ratio of R, G, B in the original pixel value (100, 150, 200) of the pixel unit, and the display brightness of each R, G, B sub-pixel remains unchanged to ensure the display effect of the virtual image. The original backlight brightness of the backlight module can be a preset brightness value, or determined according to the external ambient light brightness, the brightness value set by the user, the currently displayed screen content, etc.

[0124] In some embodiments, the backlight spectrum distribution of the backlight module corresponds to the light transmission spectrum distribution of the liquid crystal display screen 101 .

[0125] Specifically, the backlight spectrum distribution corresponds to the light transmission spectrum distribution of the liquid crystal display screen 101, that is, the light emission spectrum distribution of the light source element in the backlight module matches the light transmission spectrum distribution of the liquid crystal display screen 101, which may specifically include at least one of the following:

[0126] In the emission spectrum of the light source element, the peak wavelength of the red light is greater than the wavelength value corresponding to the red light transmittance in the red light transmittance spectrum of the liquid crystal display when the transmittance is 50% of the maximum red light transmittance;

[0127] In the luminous spectrum of the light source element, the red light is within the wavelength range of 600nm-660nm, and the wavelength value corresponding to the red light transmittance spectrum of the liquid crystal display screen when the transmittance is 50% of the maximum red light transmittance is greater than 570nm;

[0128] In the emission spectrum of the light source element, the peak wavelength of green light is consistent with the peak wavelength in the green light transmission spectrum of the liquid crystal display, or the difference does not exceed a preset threshold, such as 10nm or 5nm;

[0129] The peak wavelength of the blue light in the emission spectrum of the light source element is consistent with the peak wavelength in the blue light transmission spectrum of the liquid crystal display, or the difference does not exceed a preset threshold, such as 50nm or 40nm;

[0130] In the luminous spectrum of the light source element, the wavelength range where the half-peak width of the blue light is located does not overlap with the wavelength range where the half-peak width corresponding to the green light transmission spectrum of the liquid crystal display is located;

[0131] In the light emission spectrum of the light source element, the wavelength range where the half-peak width of green light lies does not overlap with the wavelength range where the half-peak width corresponds to the blue light transmittance spectrum of the liquid crystal display, and the maximum wavelength of the wavelength range where the half-peak width of green light in the light emission spectrum of the light source element lies is smaller than the wavelength value corresponding to the red light transmittance spectrum of the liquid crystal display when the transmittance is 50% of the maximum red light transmittance.

[0132] In some embodiments, the backlight spectrum distribution corresponds to the light transmittance spectrum distribution of the liquid crystal display 101, that is, in the luminous spectrum of the light source element, the peak wavelength of red light is greater than the wavelength value corresponding to the red light transmittance spectrum of the liquid crystal display when the transmittance is 50% of the maximum red light transmittance; in the luminous spectrum of the light source element, the peak wavelength of green light is consistent with the peak wavelength in the green light transmittance spectrum of the liquid crystal display, or the difference does not exceed a preset threshold, such as 10nm or 5nm; in the luminous spectrum of the light source element, the peak wavelength of blue light is consistent with the peak wavelength in the blue light transmittance spectrum of the liquid crystal display, or the difference does not exceed The wavelength range of the half-peak width of the blue light in the luminous spectrum of the light source element does not overlap with the wavelength range of the half-peak width corresponding to the green light transmittance spectrum of the liquid crystal display; and the wavelength range of the half-peak width of the green light in the luminous spectrum of the light source element does not overlap with the wavelength range of the half-peak width corresponding to the blue light transmittance spectrum of the liquid crystal display, and the maximum wavelength of the wavelength range of the half-peak width of the green light in the luminous spectrum of the light source element is less than the wavelength value corresponding to the red light transmittance spectrum of the liquid crystal display when the transmittance is 50% of the maximum red light transmittance.

[0133] In some embodiments, the backlight spectrum distribution corresponds to the light transmittance spectrum distribution of the liquid crystal display 101, that is, in the luminous spectrum of the light source element, the red light is within the wavelength range of 600nm-660nm, and the wavelength value corresponding to the transmittance of the red light transmittance spectrum of the liquid crystal display is greater than 570nm when the transmittance is 50% of the maximum red light transmittance; in the luminous spectrum of the light source element, the peak wavelength of the green light is consistent with the peak wavelength in the green light transmittance spectrum of the liquid crystal display, or the difference does not exceed a preset threshold, such as 10nm or 5nm; in the luminous spectrum of the light source element, the peak wavelength of the blue light is consistent with the peak wavelength in the blue light transmittance spectrum of the liquid crystal display. The peak wavelengths are consistent, or the difference does not exceed a preset threshold, such as 50nm or 40nm; in the luminous spectrum of the light source element, the wavelength range where the half-peak width of blue light is located does not overlap with the wavelength range where the half-peak width corresponds to the green light transmittance spectrum of the liquid crystal display; in the luminous spectrum of the light source element, the wavelength range where the half-peak width of green light is located does not overlap with the wavelength range where the half-peak width corresponds to the blue light transmittance spectrum of the liquid crystal display, and the maximum wavelength of the wavelength range where the half-peak width of green light in the luminous spectrum of the light source element is located is less than the wavelength value corresponding to the red light transmittance spectrum of the liquid crystal display when the transmittance is 50% of the maximum red light transmittance.

[0134] The R, G, and B sub-pixels in the color filter film filter the light emitted by the light source element through the R color resistance, G color resistance, and B color resistance, respectively. In some embodiments, the transmittance of the R color resistance in each pixel unit within the wavelength range of 400nm-580nm is less than 10%; the transmittance of the G color resistance in each pixel unit within the wavelength range of 430nm-450nm is less than 5%, and the transmittance within the wavelength range of 600nm-700nm is less than 5%; the transmittance of the B color resistance in each pixel unit within the wavelength range of 500nm-700nm is less than 10%. The transparent filter in the W sub-pixel can completely transmit the light emitted by the light source element, while the R color resistance, G color resistance, and B color resistance can only transmit light in a partial band of the light source light, so after driving the W sub-pixel to emit light, the transmittance of the liquid crystal screen will be improved.

[0135] Example 2

[0136] A second embodiment of the present disclosure provides a vehicle, comprising the above-mentioned head-up display 10 .

[0137] It should be noted that the vehicles in the embodiments of the present disclosure include but are not limited to commercial vehicles and / or passenger cars.

[0138] Example 3

[0139] A third embodiment of the present disclosure provides a control method for a head-up display 10, wherein the head-up display 10 includes a liquid crystal display 101, wherein the liquid crystal display 101 includes a plurality of pixel units, each of which includes four sub-pixels, namely, W, R, G, and B. The method includes:

[0140] S101 : driving the W sub-pixel in the liquid crystal display screen 101 to adjust the transmittance of the liquid crystal display screen 101 .

[0141] Specifically, the head-up display 10 may further include a controller 102 connected to the liquid crystal display screen 101 , and the control method of the head-up display 10 is applied to the controller 102 .

[0142] In some embodiments, the controller 102 may be a driving circuit. The controller 102 may transmit a grayscale voltage to an electrode of each sub-pixel through a data line, so that each sub-pixel displays a corresponding grayscale value, thereby displaying a picture on the liquid crystal display screen 101 .

[0143] In this embodiment, by adding a W sub-pixel to each pixel unit of the liquid crystal display screen 101 and driving the sub-pixel through the controller 102, the transmittance of the liquid crystal display screen 101 can be adjusted according to the environmental information around the liquid crystal display screen 101, so that the brightness of the displayed picture in the liquid crystal display screen 101 can be adjusted, and then the brightness of the emitted image light can be adjusted, and the brightness of the virtual image formed by the head-up display 10 can be adjusted. For example, when the power consumption of the liquid crystal display screen 101 is the same, the transmittance of the liquid crystal display screen 101 can be increased, thereby increasing the brightness of the virtual image, so that the user can see the virtual image more clearly, or when the brightness of the virtual image is excessive, the brightness of the virtual image can be reduced to avoid excessive brightness of the virtual image causing damage to the human eye, etc.

[0144] The control method of the head-up display 10 provided in the embodiment of the present disclosure includes a liquid crystal display screen 101, and the liquid crystal display screen 101 includes a plurality of pixel units, each pixel unit includes four sub-pixels of W, R, G, and B. By driving the W sub-pixel in the liquid crystal display screen 101 to adjust the transmittance of the liquid crystal display screen 101, the display brightness of the virtual image formed by the head-up display 10 can be adjusted to improve the user's HUD experience. For example, the W sub-pixel in the liquid crystal display screen 101 is driven to emit light, thereby improving the transmittance of the liquid crystal display screen 101, and then the display brightness of the virtual image formed by the head-up display 10 can be improved, so that the user can view the content displayed in the virtual image more conveniently.

[0145] In some embodiments, in step S101, driving the W sub-pixel in the liquid crystal display screen 101 to adjust the transmittance of the liquid crystal display screen 101 includes:

[0146] S201 : When the head-up display 10 is in the first mode, the W sub-pixels in the liquid crystal display 101 are driven according to the ambient light brightness of the ambient space corresponding to the virtual image formed by the head-up display 10 to adjust the transmittance of the liquid crystal display 101 .

[0147] Among them, the first mode refers to a working mode of conditionally driving the W sub-pixel. The ambient light brightness of the environment space corresponding to the virtual image formed by the head-up display 10 refers to the light intensity of the environment space. For example, when the vehicle is driving in the daytime, due to the strong reflection of the white car driving in front, the ambient light brightness in front of the vehicle's field of view is brighter, and the virtual image of the virtual image may not be easily observed or recognized by the user. Therefore, the W sub-pixel can be driven to emit light to increase the transmittance of the liquid crystal display, thereby increasing the brightness of the virtual image; and when the vehicle is driving at night, the ambient light brightness is darker, and the brightness contrast between the darker ambient light and the virtual image is obvious. At this time, there is no need to increase the brightness of the virtual image by driving the W sub-pixel to emit light. Not driving the W sub-pixel to emit light can also maintain the color gamut of the liquid crystal display, ensure the color display effect of the virtual image, and avoid the problem of color display imbalance.

[0148] In order to make the brightness of the virtual image adapt to the light intensity of the ambient space so that the user can see the virtual image clearly or ensure the color display effect of the virtual image, in this embodiment, when the head-up display 10 is in the first mode, the controller 102 can drive the W sub-pixel according to the ambient light brightness of the ambient space corresponding to the virtual image formed by the head-up display, and adjust the transmittance of the liquid crystal display 101 to meet the display requirements of the virtual image under different ambient light intensities.

[0149] In some embodiments, in step S201, driving the W sub-pixel in the liquid crystal display screen 101 according to the ambient light brightness of the ambient space corresponding to the virtual image formed by the head-up display 10 includes:

[0150] S2011: If the ambient light brightness is greater than a first preset brightness threshold, driving the W sub-pixel to emit light to increase the transmittance of the liquid crystal display 101;

[0151] S2012: If the ambient light brightness is less than or equal to the first preset brightness threshold, the W sub-pixel is not driven to emit light.

[0152] When the ambient light brightness is brighter than the first preset brightness threshold, the controller 102 drives the W sub-pixel to emit light, that is, controls the W sub-pixel to start working, so as to improve the transmittance of the liquid crystal display screen 101, and can improve the brightness of the virtual image formed by the head-up display 10, so as to facilitate the user to clearly observe the virtual image content of the virtual image, such as navigation instructions, vehicle speed and other information.

[0153] When the ambient light brightness is less than or equal to the first preset brightness threshold, the controller 102 does not drive the W sub-pixel to emit light, that is, controls the W sub-pixel to turn off, which can ensure the color gamut range of the virtual image and ensure that the user can still observe the virtual image with a high color gamut when the ambient light brightness is low. The size of the color gamut represents the color range that the liquid crystal display screen 101 can display. The larger the color gamut range, the more types of colors that the liquid crystal display screen 101 can display, and the corresponding virtual image is brighter. The size of the color gamut can be a color gamut percentage (such as the NTSC standard) to describe the color reproduction ability of the display. NTSC is defined as the ratio of the area of ​​a triangle composed of three primary colors to the area of ​​a triangle composed of three primary colors of the standard NTSC under the CIE1931XYZ coordinates.

[0154] When the controller 102 drives the W sub-pixel to emit light, the color gamut range of the liquid crystal display screen 101 will be reduced, thereby reducing the color gamut range of the virtual image. Therefore, in this embodiment, when the ambient light brightness is dark, the controller 102 does not drive the W sub-pixel to emit light, that is, controls the W sub-pixel not to work, so as to maintain the color gamut range of the virtual image. In a specific implementation, the controller 102 can set the grayscale value of the W sub-pixel to 0 (completely black) and does not drive the W sub-pixel to emit light.

[0155] In some embodiments, the controller 102 does not drive the W sub-pixel to emit light, including: the controller 102 transmits a grayscale voltage corresponding to a zero grayscale value to the W sub-pixel through a data line, thereby preventing the W sub-pixel from emitting light.

[0156] In some embodiments, in step S101, driving the W sub-pixel in the liquid crystal display screen 101 to adjust the transmittance of the liquid crystal display screen 101 includes:

[0157] S301: When the head-up display 10 is in the first mode, the grayscale value of the W sub-pixel is adjusted according to a preset correspondence between the ambient light brightness corresponding to the head-up display 10 and the grayscale value of the W sub-pixel, wherein the ambient light brightness corresponding to the head-up display 10 is the ambient light brightness of the ambient space corresponding to the virtual image formed by the head-up display 10, and the grayscale value of the W sub-pixel increases with the increase of the ambient light brightness.

[0158] In some embodiments, after determining the grayscale value of the W sub-pixel according to the preset correspondence between the ambient light brightness corresponding to the head-up display 10 and the grayscale value of the W sub-pixel, the controller 102 transmits the grayscale voltage corresponding to the grayscale value to the W sub-pixel through the data line, thereby driving the W sub-pixel to emit light.

[0159] During the driving process of the vehicle, the brightness of the ambient light in front of the vehicle's field of view can be detected by an image acquisition device or a light sensor set in the vehicle, and sent to the controller 102. When the head-up display 10 is in the first mode, the controller 102 can adjust the grayscale value of the W sub-pixel according to the detected ambient light brightness and the preset correspondence between the ambient light brightness and the grayscale value of the W sub-pixel, so as to adjust the transmittance of the liquid crystal display screen 101 so that the ambient light brightness matches the brightness of the virtual image. The grayscale value of the W sub-pixel can be adjusted between 0 and 255, wherein grayscale 0 is completely black, and the W sub-pixel does not emit light (that is, the light incident on the W sub-pixel cannot pass through the W sub-pixel), and grayscale 255 is completely white, and the W sub-pixel emits light and has the maximum brightness (that is, the light incident on the W sub-pixel can all pass through the W sub-pixel), thereby improving the transmittance of the liquid crystal display screen 101.

[0160] In this embodiment, the grayscale value of the W sub-pixel increases with the increase of the ambient light brightness, that is, the transmittance of the liquid crystal display screen 101 increases with the increase of the ambient light brightness, thereby increasing the brightness of the virtual image.

[0161] It is understandable that when the controller 102 adjusts the grayscale value of the W sub-pixel, the grayscale values ​​of the R, G, and B sub-pixels can be controlled to remain unchanged. For example, in a certain pixel unit in the liquid crystal display screen 101, the original grayscale values ​​of the R, G, and B sub-pixels are (100, 150, 200), and after the W sub-pixel is adjusted, the grayscale values ​​of the R, G, B, and W sub-pixels are (100, 150, 200, 50). In each pixel unit, the original grayscale value (or target grayscale value) of the R, G, and B sub-pixels can be determined according to the video / image signal transmitted by the signal source of the liquid crystal display screen. When the liquid crystal display screen is scanned and driven, the controller 102 transmits the grayscale voltage corresponding to the target grayscale value to the R, G, and B sub-pixels in each pixel unit in turn, and transmits the grayscale voltage corresponding to its grayscale value to the W sub-pixel, so that the liquid crystal display screen displays the video / image screen transmitted by the signal source.

[0162] The preset corresponding relationship between the ambient light brightness corresponding to the head-up display 10 and the grayscale value of the W sub-pixel can be predetermined according to actual needs. For example, different W sub-pixel grayscale values ​​can be configured for different ambient light brightness ranges (the ambient light brightness range and the grayscale value of the W sub-pixel are in a discrete relationship), and the ambient light brightness and the grayscale value of the W sub-pixel can also be in a linear relationship or a non-linear relationship (such as a curve relationship), etc., and the present disclosure is not limited to this.

[0163] It can be understood that, in the present embodiment, the controller 102 drives the W sub-pixel to emit light or does not drive the W sub-pixel to emit light by adjusting the grayscale value of the W sub-pixel. When the grayscale value of the W sub-pixel is 0, the controller 102 does not drive the W sub-pixel to emit light. When the grayscale value of the W sub-pixel is any value between (0, 255], the controller 102 drives the W sub-pixel to emit light, and the light luminance of the W sub-pixel is adjusted as the brightness of the ambient light changes.

[0164] In some embodiments, in step S101, driving the W sub-pixel in the liquid crystal display screen 101 to adjust the transmittance of the liquid crystal display screen 101 includes:

[0165] S401 : When the head-up display 10 is in the second mode, the W sub-pixel in each pixel unit of the liquid crystal display screen 101 is driven according to the grayscale values ​​of the three sub-pixels R, G, and B in each pixel unit to improve the transmittance of the liquid crystal display screen 101 .

[0166] The second mode includes a working mode in which the W sub-pixel is always on, in which the W sub-pixel is always emitting light. In this embodiment, when the controller 102 drives the W sub-pixel in a certain pixel unit to emit light, the target grayscale value to be adjusted for the W sub-pixel can be determined according to the grayscale values ​​of the three R, G, and B sub-pixels in the pixel unit (i.e., the original grayscale values ​​of the three R, G, and B sub-pixels), and then the grayscale value of the W sub-pixel is adjusted according to the target grayscale value, thereby improving the transmittance of the liquid crystal display screen 101 and the brightness of the virtual image.

[0167] In some embodiments, in step S401, driving the W sub-pixel in each pixel unit in the liquid crystal display screen 101 according to the grayscale values ​​of the three sub-pixels R, G, and B in the pixel unit includes:

[0168] S4011: Determine the adjusted grayscale value of the W sub-pixel according to the grayscale values ​​of the three sub-pixels R, G, and B in each of the pixel units;

[0169] S4012: updating the grayscale values ​​of the three R, G, and B sub-pixels according to the adjusted grayscale value of the W sub-pixel.

[0170] When the W sub-pixel in a pixel unit in the liquid crystal display screen 101 is driven to emit light according to the grayscale values ​​of the three sub-pixels R, G, and B in a certain pixel unit, the grayscale value of the W sub-pixel can be determined according to the minimum grayscale value of the three sub-pixels R, G, and B, wherein the W sub-pixel can be the minimum value of the grayscale values ​​of the three sub-pixels R, G, and B or other values ​​less than the minimum value. For example, the grayscale values ​​of the three sub-pixels R, G, and B in a certain pixel unit are (100, 150, 200) respectively, and the grayscale value of the W sub-pixel can be the minimum value 100 therein. After adjusting the grayscale value of the W sub-pixel according to the grayscale value, the grayscale values ​​of the three sub-pixels R, G, and B can be updated to ensure the overall display effect of the virtual image. For example, the original grayscale values ​​of the R, G, and B sub-pixels are subtracted from the grayscale value of the W sub-pixel, and the updated grayscale values ​​of the R, G, and B sub-pixels can be (0, 50, 100).

[0171] In some embodiments, the head-up display 10 further includes a backlight module for providing backlight for the liquid crystal display screen 101, and the method further includes:

[0172] S501: Control the backlight module to emit light.

[0173] The backlight module may include a plurality of light source elements, and the light source elements are used to emit light source light. The light source light is incident on the liquid crystal display screen 101, and is converted into image light by the liquid crystal display screen 101 and then emitted.

[0174] The controller 102 can control the backlight module to emit light and drive the R, G, B, and W sub-pixels of the liquid crystal display screen 101 to emit light. The light source light (white light) emitted by the backlight module can be filtered by the R, G, and B sub-pixels into R, G, and B colored light, and mixed to form colorful colored light. Through the high transmittance of the W sub-pixel, the transmittance of the liquid crystal display screen 101 can be increased without changing the backlight brightness, and the brightness of the virtual image can be increased, which is convenient for users to watch. The backlight module can be an LED (Light Emitting Diode) light-emitting element.

[0175] Exemplarily, when the ambient light is bright, the ambient light incident on the liquid crystal display screen 101 will cause the liquid crystal display screen 101 to heat up, and the high power consumption of the backlight module will also cause the liquid crystal display screen 101 to heat up. In order to extend the life of the liquid crystal display screen 101 or prevent the liquid crystal display screen 101 from being burned, the backlight of the head-up display 10 will only be turned on to a certain brightness value. At this time, the virtual image of the virtual image may not be easily observed or recognized by the user. Therefore, in this embodiment, the transmittance of the liquid crystal display screen 101 is increased by driving the W sub-pixel by the controller 102, and the brightness of the virtual image can be increased while the backlight brightness (backlight power consumption) remains unchanged, so as to facilitate the user to watch. When the ambient light is dark, it is not necessary to increase the brightness of the virtual image, and only the brightness of the display screen on the liquid crystal display screen 101 can be kept unchanged. At this time, the backlight brightness of the backlight module can be reduced, thereby reducing the backlight power consumption, and keeping the brightness and color of the virtual image unchanged, that is, under the premise of meeting the brightness and color requirements of the virtual image, the backlight power consumption is reduced, and the service life of the head-up display 10 is extended.

[0176] In some embodiments, in step S501, controlling the backlight module to emit light includes:

[0177] S5011: Determine the transmittance of the liquid crystal display screen 101 and determine the preset brightness corresponding to the virtual image formed by the head-up display 10;

[0178] S5012: Determine the backlight brightness of the liquid crystal display screen 101 according to the transmittance of the liquid crystal display screen 101 and the preset brightness corresponding to the virtual image;

[0179] S5013: adjusting the light emitting brightness of the backlight module according to the backlight brightness of the liquid crystal display screen 101.

[0180] Specifically, the controller 102 can calculate the transmittance of the liquid crystal display screen 101 according to the grayscale values ​​of the R, G, B, and W sub-pixels of all pixel units in the current liquid crystal display screen 101; or, by detecting the current screen brightness of the liquid crystal display screen and the luminous brightness of the backlight source, calculate the current transmittance of the liquid crystal display screen. Then, according to the preset brightness value corresponding to the virtual image formed by the head-up display 10 and the calculated transmittance of the liquid crystal display screen 101, the backlight brightness value of the liquid crystal display screen 101 at this time is calculated. The backlight brightness value of the liquid crystal display screen 101 is obtained by substituting the preset brightness value corresponding to the virtual image formed by the head-up display 10 and the transmittance of the liquid crystal display screen 101 according to the formula: liquid crystal display screen brightness = backlight brightness * liquid crystal display transmittance. After determining the backlight brightness of the liquid crystal display screen 101, the luminous brightness of the backlight module can be controlled according to the backlight brightness to reduce the backlight power consumption. For example, in this embodiment, after adjusting the grayscale values ​​of the R, G, and B sub-pixels according to the grayscale value of the W sub-pixel, the transmittance of the adjusted LCD display 101 is determined, and then the luminous brightness of the optical module is adjusted to reduce backlight power consumption.

[0181] In some embodiments, the backlight module includes a plurality of light source elements, and the method further includes:

[0182] S601: Divide the display area of ​​the liquid crystal display screen 101 into a plurality of sub-areas, and determine a corresponding relationship between each sub-area and a light source element in the backlight module that provides backlight for the sub-area;

[0183] S602: When the image to be displayed on the liquid crystal display screen 101 includes target picture content, determine a target sub-region covered by the target picture content and other sub-regions in the display region except the target sub-region;

[0184] S603: When the ambient light brightness is less than or equal to the first preset brightness threshold, drive the W sub-pixels in the target sub-region to emit light, and do not drive the W sub-pixels in the other sub-regions to emit light.

[0185] Among them, when the ambient light brightness is less than or equal to the first preset brightness threshold, for example, at night, when the image to be displayed on the LCD screen 101 contains target screen content (such as electronic rearview mirror image, reversing image and other screen content), the target sub-area covered by the target screen content can be determined, that is, when the LCD screen 101 displays the image to be displayed, the target screen content is displayed in the target sub-area. The target sub-area can be multiple sub-areas, for example, the electronic rearview mirror image is displayed in sub-area 1 to sub-area 4, and each sub-area in sub-area 1 to sub-area 4 displays part of the content in the electronic rearview mirror image. In order to improve the display brightness of the target screen content, the W sub-pixel located in the target sub-area can be driven to emit light, so as to facilitate the user to watch the target screen content. The W sub-pixel in the target sub-region is driven to emit light, for example, the grayscale value of each W sub-pixel in the target sub-region may be set to a default grayscale value; or the grayscale value of the W sub-pixel may be determined according to the grayscale values ​​of the three R, G, and B sub-pixels in the pixel unit where each W sub-pixel is located, for example, the grayscale value of the W sub-pixel may be determined according to the minimum grayscale value of the three R, G, and B sub-pixels, wherein the W sub-pixel may be the minimum value of the grayscale values ​​of the three R, G, and B sub-pixels or other values ​​less than the minimum value.

[0186] In some embodiments, the method further comprises:

[0187] S502: After adjusting the light emitting brightness of the backlight module according to the backlight brightness of the liquid crystal display screen 101, the grayscale value of at least one sub-pixel among the three sub-pixels R, G, and B is compensated.

[0188] After reducing the backlight power consumption (i.e., adjusting the backlight brightness of the backlight module), the reduction in backlight brightness will cause a loss in the display brightness of the sub-pixels with non-zero grayscale in the R, G, and B sub-pixels. For example, when the grayscale value of the W sub-pixel is determined to be 100 and the updated grayscale values ​​of the R, G, and B sub-pixels are calculated to be (0, 50, 100), the backlight brightness is reduced (for example, reduced to 50 cd / m 2 ) will cause the display brightness of the G and B sub-pixels to fall short of the original backlight brightness (e.g. 70 cd / m 2 ) case, the display brightness of the G and B sub-pixels with grayscales of 50 and 100 respectively. Therefore, after reducing the backlight power consumption, it is necessary to compensate the grayscale values ​​of the G and B sub-pixels (that is, increase the grayscale values ​​of the G and B sub-pixels) to a certain extent, so as to ensure that after the compensated R, G, B, W are converted into RGB, the ratio of the R, G, B components is the same as the ratio of R, G, B in the original pixel value (100, 150, 200) of the pixel unit, and the display brightness of the R, G, B sub-pixels remains unchanged to ensure the display effect of the virtual image.

[0189] The control method of the vehicle and the head-up display corresponds to the head-up display in the above-mentioned embodiment. Any optional items in the head-up display device embodiment are also applicable to the embodiment of the control method of the vehicle and the head-up display, which will not be repeated here.

[0190] The above description is only a preferred embodiment of the present disclosure and an explanation of the technical principles used. Those skilled in the art should understand that the scope of disclosure involved in the present disclosure is not limited to the technical solutions formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the above disclosed concept. For example, the above features are replaced with the technical features with similar functions disclosed in the present disclosure (but not limited to) by each other to form a technical solution.

Claims

1. A head-up display, comprising a liquid crystal display and a controller, characterized in that: The liquid crystal display screen includes a plurality of pixel units, each of which includes four sub-pixels: W, R, G, and B. The controller is connected to the liquid crystal display screen, and is configured to drive the W sub-pixel in the liquid crystal display screen to adjust the transmittance of the liquid crystal display screen.

2. The head-up display according to claim 1, characterized in that: In each of the pixel units, the proportion of the area occupied by the W sub-pixel in the pixel unit is greater than or equal to 1 / 5 and less than or equal to 4 / 5.

3. The head-up display according to claim 1, characterized in that: The controller is configured to drive the W sub-pixel in the liquid crystal display to adjust the transmittance of the liquid crystal display, including: When the head-up display is in the first mode, the controller is configured to drive the W sub-pixel in the liquid crystal display screen according to the ambient light brightness of the ambient space corresponding to the virtual image formed by the head-up display screen to adjust the transmittance of the liquid crystal display screen.

4. The head-up display according to claim 3, characterized in that: The controller is configured to drive the W sub-pixel in the liquid crystal display screen according to the ambient light brightness of the ambient space corresponding to the virtual image formed by the head-up display, including: If the ambient light brightness is greater than a first preset brightness threshold, the controller is configured to drive the W sub-pixel to emit light to increase the transmittance of the liquid crystal display; If the ambient light brightness is less than or equal to the first preset brightness threshold, the controller is configured not to drive the W sub-pixel to emit light.

5. The head-up display according to claim 1, characterized in that: The controller is configured to drive the W sub-pixel in the liquid crystal display to adjust the transmittance of the liquid crystal display, including: When the head-up display is in the first mode, the controller is configured to adjust the grayscale value of the W sub-pixel according to a preset correspondence between the ambient light brightness corresponding to the head-up display and the grayscale value of the W sub-pixel, wherein the ambient light brightness corresponding to the head-up display is the ambient light brightness of the ambient space corresponding to the virtual image formed by the head-up display, and the grayscale value of the W sub-pixel increases with the increase of the ambient light brightness.

6. The head-up display according to claim 1, characterized in that: The controller is configured to drive the W sub-pixel in the liquid crystal display to adjust the transmittance of the liquid crystal display, including: When the head-up display is in the second mode, the controller is configured to drive the W sub-pixel in each pixel unit in the liquid crystal display screen according to the grayscale values ​​of the three sub-pixels R, G, and B in each pixel unit to improve the transmittance of the liquid crystal display screen.

7. The head-up display according to claim 6, characterized in that: The controller is configured as follows: Determine the grayscale value of the W sub-pixel according to the grayscale values ​​of the three sub-pixels R, G, and B in each of the pixel units; The grayscale values ​​of the three R, G, and B sub-pixels are updated according to the adjusted grayscale value of the W sub-pixel.

8. The head-up display according to claim 1, characterized in that: The head-up display further includes a backlight module for providing backlight for the liquid crystal display screen. The controller is connected to the backlight module, and the controller is configured to control the backlight module to emit light.

9. The head-up display according to claim 8, characterized in that: The backlight module excites the yellow phosphor through the blue chip to emit white light; or The backlight module excites red and green phosphors through a blue chip to emit white light; or The backlight module emits red, green and blue light respectively through red, green and blue chips, and the red, green and blue light are mixed to emit white light.

10. The head-up display according to claim 8, characterized in that: The controller is configured as follows: Determining the transmittance of the liquid crystal display screen and determining a preset brightness corresponding to the virtual image formed by the head-up display; Determining the backlight brightness of the liquid crystal display screen according to the transmittance of the liquid crystal display screen and the preset brightness corresponding to the virtual image; The light emitting brightness of the backlight module is adjusted according to the backlight brightness of the liquid crystal display screen.

11. The head-up display according to claim 10, characterized in that: The controller is further configured to compensate the grayscale value of at least one of the three sub-pixels R, G, and B after adjusting the light emitting brightness of the backlight module according to the backlight brightness of the liquid crystal display.

12. The head-up display according to claim 8, characterized in that: The backlight spectrum distribution of the backlight module corresponds to the light transmission spectrum distribution of the liquid crystal display screen.

13. The head-up display according to any one of claims 3 to 5, characterized in that: The controller is also configured to: Capturing an image of the environment in front of the vehicle by an image acquisition device disposed on the vehicle; The ambient light brightness of the ambient space corresponding to the virtual image formed by the head-up display is determined according to the brightness of the ambient image.

14. The head-up display according to claim 4, characterized in that: The head-up display further includes a backlight module for providing backlight for the liquid crystal display screen, the backlight module includes a plurality of light source elements, and the controller is further configured as follows: Dividing the display area of ​​the liquid crystal display screen into a plurality of sub-areas, and determining a corresponding relationship between each sub-area and a light source element in the backlight module that provides backlight for the sub-area; In a case where the image to be displayed on the liquid crystal display screen includes target picture content, determining a target sub-region covered by the target picture content and other sub-regions in the display region except the target sub-region; When the ambient light brightness is less than or equal to the first preset brightness threshold, the W sub-pixels in the target sub-region are driven to emit light, and the W sub-pixels in the other sub-regions are not driven to emit light.

15. The head-up display according to claim 1, characterized in that: The transmittance of the R color resist in each of the pixel units within the wavelength range of 400nm-580nm is less than 10%; the transmittance of the G color resist in each of the pixel units within the wavelength range of 430nm-450nm is less than 5%, and the transmittance within the wavelength range of 600nm-700nm is less than 5%; the transmittance of the B color resist in each of the pixel units within the wavelength range of 500nm-700nm is less than 10%.

16. A vehicle, characterized in that: A heads-up display comprising the following claim 1.

17. A method for controlling a head-up display, characterized in that: The head-up display includes a liquid crystal display screen, the liquid crystal display screen includes a plurality of pixel units, each of the pixel units includes four sub-pixels of W, R, G, and B, and the method includes: The W sub-pixel in the liquid crystal display is driven to adjust the transmittance of the liquid crystal display.

18. The method according to claim 17, characterized in that Driving the W sub-pixel in the liquid crystal display screen to adjust the transmittance of the liquid crystal display screen includes: When the head-up display is in the first mode, the W sub-pixel in the liquid crystal display is driven according to the ambient light brightness of the ambient space corresponding to the virtual image formed by the head-up display to adjust the transmittance of the liquid crystal display.

19. The method according to claim 18, characterized in that Driving the W sub-pixel in the liquid crystal display screen according to the ambient light brightness of the ambient space corresponding to the virtual image formed by the head-up display includes: If the ambient light brightness is greater than a first preset brightness threshold, driving the W sub-pixel to emit light to increase the transmittance of the liquid crystal display; If the ambient light brightness is less than or equal to the first preset brightness threshold, the W sub-pixel is not driven to emit light.

20. The method according to claim 17, characterized in that Driving the W sub-pixel in the liquid crystal display screen to adjust the transmittance of the liquid crystal display screen includes: When the head-up display is in the second mode, the W sub-pixel in each pixel unit in the liquid crystal display is driven according to the grayscale values ​​of the three sub-pixels R, G, and B in each pixel unit to improve the transmittance of the liquid crystal display.

21. The method according to claim 17, characterized in that The head-up display further includes a backlight module for providing backlight for the liquid crystal display screen, and the method further includes: controlling the backlight module to emit light.

22. The method according to claim 21, characterized in that Controlling the backlight module to emit light, comprising: Determining the transmittance of the liquid crystal display screen and determining a preset brightness corresponding to the virtual image formed by the head-up display; Determining the backlight brightness of the liquid crystal display screen according to the transmittance of the liquid crystal display screen and the preset brightness corresponding to the virtual image; The light emitting brightness of the backlight module is adjusted according to the backlight brightness of the liquid crystal display screen.

Images