Display device and vehicle

Abstract

The invention discloses a display device and a vehicle, and belongs to the technical field of display. The display device comprises an image source, an image transmission assembly and an optical assembly, wherein the image source is used for emitting image light; the image transmission assembly is used for translating and transmitting image light emitted by the image source to a light emitting surface of the image transmission assembly, and diffusing and transmitting the image light emitted by the light emitting surface to the optical assembly; the optical assembly is used for reflecting the image light to a windshield, so that the image light forms a virtual image through the windshield. The display device can prevent the temperature of the image source from being too high.

Description

Technical Field

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

[0002] Display devices, such as head-up displays (HUDs), are widely used in people's daily lives.

[0003] In the related art, the display device generally includes an image source, an image transmission component and an optical component. The image source is used to emit image light. The image transmission component is used to diffuse the received image light and transmit it to the optical component. The optical component is used to form a virtual image based on the received image light.

[0004] When the external ambient light (such as sunlight) is strong, light backflow may occur, that is, a large amount of light is continuously focused on the image source along the optical components and image transmission components, causing the temperature of the image source to be too high, thereby affecting the display effect of the image source and even damaging the image source. Summary of the invention

[0005] The present application provides a display device and a vehicle, which can reduce the damage of external ambient light to the image source of the display device.

[0006] In a first aspect, the present application provides a display device, which includes an image source, an image transmission component, and an optical component. The image source is used to emit image light. The image transmission component is used to translate and transmit the image light emitted by the image source to a light-emitting surface of the image transmission component, and diffusely transmit the image light emitted by the light-emitting surface to the optical component, and the optical component is used to reflect the image light to a windshield, so that the image light forms a virtual image through the windshield.

[0007] In the process of virtual image formation, the size of the virtual image is related to the size relationship between the object distance and the effective focal length of the optical system (including optical components and windshield). The closer the object distance is to the effective focal length of the optical system, the greater the magnification of the virtual image and the greater the virtual image distance.

[0008] In the present application, the image transmission component is used to transfer the image light emitted by the image source to the light-emitting surface of the image transmission component, and diffusely transfer the image light emitted by the light-emitting surface to the optical component, which is equivalent to the light-emitting surface being the object plane of the optical system, and the distance between the light-emitting surface and the optical component being the object distance of the optical system. When the object distance is close to the effective focal length of the optical system, since the object plane is obtained by the image transmission component transferring the image light, there is a certain distance between the image source and the focus of the optical system.

[0009] When external ambient light passes through the optical system and enters the display device, it will be focused at the focal point of the optical system. There is a certain distance between the image source and the focal point of the optical system. Therefore, it can prevent the image source from being continuously focused and irradiated, thereby preventing the temperature of the image source from being too high, reducing the damage of the external ambient light to the image source of the display device.

[0010] In the present application, translational transmission means that the change in diffusion angle after the light emitted by any sub-pixel of the image source is propagated along the light emitting direction of the image source (i.e., the direction perpendicular to the light emitting plane of the image source) is less than or equal to a threshold value, and the value of the threshold value depends on the crosstalk between the sub-pixels of the image light after the translational transmission. When the change in diffusion angle is less than or equal to the threshold value, the crosstalk between the sub-pixels of the image light after the translational transmission is small and will not affect the display effect. In an ideal state, the threshold value is 0.

[0011] Diffusion transmission refers to transmitting the image light emitted from the light-emitting surface to the optical component at a target diffusion angle. The target diffusion angle can be set according to actual needs.

[0012] In the present application, the display device may be a HUD, especially an augmented reality (AR)-HUD. This is because for an AR-HUD, the magnification of the virtual image generated is relatively large, so the light convergence ability of the optical component is correspondingly stronger, which is more likely to cause the problem of temperature rise.

[0013] The distance between the light-emitting surface and the optical component is less than the effective focal length of the optical system, and the optical system includes the optical component and the windshield. In this way, after the image light passes through the optical component and the windshield, an enlarged virtual image can be formed. The distance between the light-emitting surface and the optical component can be determined according to the target size of the virtual image.

[0014] In the embodiment of the present application, the sum of the distance between the image source and the light emitting surface and the distance between the light emitting surface and the optical component is greater than the effective focal length of the optical system. That is, the distance between the image source and the optical component is greater than the effective focal length of the optical system. Generally, the light entering the interior of the display device along the reverse direction of the propagation path of the image light is focused at the effective focal length of the optical system. The distance between the image source and the optical component is greater than the effective focal length of the optical system, which can prevent the light entering the interior of the display device along the reverse direction of the propagation path of the image light from being focused on the imaging source, thereby avoiding the adverse effects of excessive temperature on the imaging source.

[0015] Optionally, the target diffusion angle may be determined according to the display effect and the size of the virtual image. In some examples, the target diffusion angle may be greater than the diffusion angle of the image light emitted by the image source and less than or equal to 60 degrees.

[0016] Exemplarily, the imaging source is a direct imaging image source, which includes 2D imaging devices such as a liquid crystal display (LCD), an organic light-emitting diode (OLED) display, or a light-emitting diode (LED) display.

[0017] In a possible embodiment, the image transmission component includes a diffuser and an image translation medium, the image translation medium is located between the image source and the diffuser, the light emitting surface is the side of the diffuser close to the optical component, and the image translation medium is used to transmit the image light to the light emitting surface in a translational manner.

[0018] Optionally, the image translation medium comprises a homogeneous medium. The refractive index of the homogeneous medium is 1 to 2, for example, 1 to 1.6. When the image light passes through the homogeneous medium with a refractive index within this range, the diffusion angle remains substantially unchanged.

[0019] In some examples, the homogeneous medium may be air. In other examples, the homogeneous medium may be glass or the like.

[0020] Optionally, in order to improve the light efficiency of the system, the transmittance of the uniform medium may be above 90%.

[0021] In this embodiment, the image light emitted by the image source is collimated light, which is not collimated light in the true sense, but may be light with a diffusion angle of 0° to 5°. For example, the diffusion angle of the image light emitted by the image source is less than or equal to 1°, so as to better ensure the display quality corresponding to the image light after translation transmission.

[0022] In another possible implementation, the image source includes a plurality of sub-pixels arranged in an array. The image transmission component includes an optical fiber array, and the optical fiber array includes a plurality of optical fibers arranged in an array. The light emitted by each sub-pixel is transmitted through at least one of the plurality of optical fibers. And the light emitted by different sub-pixels passes through different optical fibers.

[0023] The propagation of light in optical fiber depends on the total reflection of light in the optical fiber. When image light propagates in the optical fiber, light with an incident angle greater than the total reflection angle cannot pass through the optical fiber. Therefore, the properties of the optical fiber can be used to suppress the change in the diffusion angle of the image light and realize the translational transmission of the image light.

[0024] Exemplarily, each sub-pixel corresponds to a plurality of optical fibers, and the light emitted by each sub-pixel is transmitted from the corresponding plurality of optical fibers to the aforementioned light-emitting surface. Here, the orthographic projection of each optical fiber on the surface of the image source is located within the light-emitting region of the corresponding sub-pixel. That is, the aperture of each optical fiber is smaller than the width of the corresponding sub-pixel in the image source.

[0025] In some examples, the ratio of the sum of the cross-sectional areas of the plurality of optical fibers through which the light emitted by each sub-pixel passes to the light emitting area of ​​the sub-pixel is 70% to 90%. When this condition is met, the light emitted by each sub-pixel can be transmitted through the corresponding optical fiber as much as possible, which is conducive to improving the light efficiency.

[0026] Optionally, the numerical aperture of the optical fiber is greater than or equal to the sine value of half the diffusion angle of the image light, and the numerical aperture of the optical fiber is less than the sine value of half the focusing angle of the external ambient light after entering the display device. When the numerical aperture of the optical fiber satisfies this relationship, the light intensity focused on the image source can be significantly reduced.

[0027] In this embodiment, the image light emitted by the image source is collimated light, and the diffusion angle is 0° to 40°. Since the optical fiber suppresses the change of the diffusion angle of the image light, the collimation degree of the image light is relatively low. The diffusion angle of the image light can be made relatively large, for example, 5° to 30°. In some examples, the diffusion angle of the image light emitted by the image source is 10° to 25°.

[0028] When the image source is an LCD, the image source includes a backlight source and a liquid crystal display panel, the liquid crystal display panel is located between the backlight source and the image transmission component, and the diffusion angle of the image light is the collimation angle of the backlight source.

[0029] Optionally, the display device further comprises a three-dimensional display device, and the three-dimensional display device is located between the light-emitting surface of the image transmission component and the optical component. By providing the three-dimensional display device, the display device can have a three-dimensional display function.

[0030] Optionally, the three-dimensional display device includes a cylindrical lens array, or a parallax barrier.

[0031] Exemplarily, the optical component includes at least one reflector, and the at least one reflector is used to reflect the image light from the image light transmission component once or multiple times so that the image light can be emitted to the windshield, thereby forming a virtual image.

[0032] Optionally, the display device further comprises a main processor. The main processor is used to send image data to an image source, and the image source is used to provide image light based on the received image data.

[0033] In some examples, the display device also includes a power supply for powering the main processor and the image source.

[0034] In a second aspect, the present application provides a means of transport, the means of transport comprising any of the aforementioned display devices. The display device is installed on the means of transport. Exemplarily, the means of transport includes but is not limited to a car, an airplane, a train, or a ship. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a schematic diagram of a display device in use provided by an embodiment of the present application;

[0036] Figure 2 is a structural schematic diagram of a display device provided in an embodiment of the present application;

[0037] Figure 3 is a simplified optical path schematic diagram of a display device provided in an embodiment of the present application;

[0038] Figure 4 is a schematic structural diagram of another display device provided in an embodiment of the present application;

[0039] Figure 5 is a structural schematic diagram of yet another display device provided in an embodiment of the present application;

[0040] Figure 6 is a structural schematic diagram of another display device provided in an embodiment of the present application;

[0041] Figure 7 is a schematic diagram of the relationship between sub-pixels and optical fibers in an embodiment of the present application;

[0042] Figure 8 is a structural schematic diagram of another display device provided in an embodiment of the present application;

[0043] Fig. 9 is a circuit diagram of a display device provided in an embodiment of the present application;

[0044] Fig.10 A functional schematic diagram of a vehicle provided in an embodiment of the present application. DETAILED DESCRIPTION

[0045] The display device provided in the embodiment of the present application is described in detail below in conjunction with the accompanying drawings. Figure 1 As shown in 100, the display device is installed on the vehicle as a head-up display (HUD), and the physical size, display size, and resolution of the display device can be adjusted according to the usage scenario. In this application, the display device can also be called a virtual image display device or a virtual image display system.

[0046] Since HUD is mainly used in transportation, such as vehicles, it spends a long time outdoors and is more likely to be exposed to strong light. Therefore, the display device provided in the embodiment of the present application is particularly suitable for HUD, especially augmented reality (AR)-HUD. This is because, for AR-HUD, the magnification of the virtual image generated is relatively large, so the light convergence ability of the optical component is correspondingly stronger, which is more likely to cause the problem of temperature rise.

[0047] Figure 2 is a schematic diagram of the structure of a display device provided in an embodiment of the present application. Figure 2 As shown, the display device includes an image source 10, an image transmission component 20 and an optical component 30. The image source 10 is used to emit image light. The image transmission component 20 is used to translate and transmit the image light emitted by the image source 10 to the light emitting surface 20a of the image transmission component 20, and to diffusely transmit the image light emitted from the light emitting surface 20a to the optical component 30. The optical component 30 is used to reflect the image light to the windshield S, so that the image light forms a virtual image through the windshield S.

[0048] In the embodiment of the present application, image light refers to a light beam carrying image information. The image light emitted by the image source 10 is transmitted through the image transmission component 20 and reaches the optical component 30. The optical component 30 reflects the image light to the windshield S, and the image light is reflected to the human eye through the windshield S, so that the user can see the magnified virtual image.

[0049] During the formation of the virtual image, the size of the virtual image is related to the size relationship between the object distance and the effective focal length of the optical system (including the optical component 30 and the windshield S). The closer the object distance is to the effective focal length of the optical system, the greater the magnification of the virtual image and the greater the virtual image distance.

[0050] In the present application, the image transmission component 20 is used to transfer the image light emitted by the image source 10 to the light-emitting surface 20a of the image transmission component 20, and diffusely transfer the image light emitted by the light-emitting surface 20a to the optical component 30. The light-emitting surface 20a is equivalent to the object plane of the optical system, and the distance between the light-emitting surface 20a and the optical component 30 is the object distance of the optical system. When the object distance is close to the effective focal length of the optical system, since the object plane is obtained by the image transmission component transferring the image light, there is a certain distance between the image source and the focus of the optical system.

[0051] When external ambient light passes through the optical system and enters the display device, it will be focused at the focus of the optical system. There is a certain distance between the image source 10 and the focus of the optical system. Therefore, it can prevent the image source 10 from being continuously focused and irradiated, thereby preventing the temperature of the image source 10 from being too high, reducing the damage of the external ambient light to the image source 10 of the display device.

[0052] In the embodiment of the present application, translational transmission refers to the change in the diffusion angle after the light emitted by any sub-pixel of the image source is propagated along the light emitting direction of the image source (i.e., the direction perpendicular to the light emitting plane of the image source) is less than or equal to a threshold value. The value of the threshold value depends on the crosstalk between the sub-pixels of the image light after the translational transmission. When the change in the diffusion angle is less than or equal to the threshold value, the crosstalk between the sub-pixels of the image light after the translational transmission is small and will not affect the display effect. In an ideal state, the threshold value is 0. In other words, the image displayed by the image source directly viewed by the user and the image viewed by the image light after the translational transmission are basically the same.

[0053] Diffusion transmission refers to transmitting the image light emitted from the light-emitting surface to the optical component at a target diffusion angle. The target diffusion angle can be set according to actual needs.

[0054] In the embodiment of the present application, the image source 10 may be a direct imaging image source. The direct imaging image source generally adopts a display screen, such as an LCD, an organic light emitting diode, an OLED display screen or an LED display screen. Among them, the LED display screen may be a micro LED display screen, or a mini LED display screen, etc.

[0055] The optical component 30 includes at least one reflector 31, which is used to reflect the image light from the image transmission component 20 once or multiple times, so that the image light can be emitted to the windshield and reflected to the human eye through the windshield, thereby forming a virtual image. Through the optical component 30, the installation direction and position of the image source 10 and the image transmission component 20 can be flexibly arranged.

[0056] Optionally, the reflector in the optical component 30 includes at least one of a curved reflector and a flat reflector. Figure 2 In the embodiment, the optical component 30 includes a curved reflector 31. In other embodiments, the optical component 30 may include a plane reflector and a curved reflector which are sequentially arranged on the emission path of the image light.

[0057] When implemented, the combination of the image source 10 and the image transmission component 20 may be referred to as a picture generation unit (PGU).

[0058] Figure 3is a simplified optical path diagram of the display device provided in the embodiment of the present application. Figure 3 As shown, the effective focal length of the optical system, the distance between the light-emitting surface 20a and the optical component 30 (ie, the object distance), and the image distance of the virtual image A satisfy the following formula (1).

[0059]

[0060] In formula (1), Z1 represents the object distance, Z2 represents the image distance, and f EL Indicates the effective focal length of an optical system.

[0061] like Figure 3 As shown, the distance between the light-exiting surface 20a and the optical component 30 is less than the effective focal length of the optical system. When this condition is met, the optical component 30 can form a virtual image A based on the image light emitted from the light-exiting surface 20a. Under this premise, the size of the virtual image A can be adjusted by controlling the distance between the light-exiting surface 20a and the focus of the optical component 30.

[0062] The sum of the distance between the image source 10 and the light emitting surface 20a and the distance between the light emitting surface 20a and the optical component 30 is greater than the effective focal length of the optical system. That is, the image source, the light emitting surface and the effective focal length of the optical system satisfy the following formula (2).

[0063] D+z1>f EL (2)

[0064] In formula (2), D represents the distance between the image source and the light emitting surface, and the meanings of other parameters are the same as those in formula (1).

[0065] In this way, when the external ambient light passes through the optical component and irradiates the inside of the display device, it is focused at the focal point of the optical component, while the image source is not at the focal point, so the external ambient light will not be focused and irradiated on the image source. In addition, since the distance between the image source and the optical component is greater than the effective focal length of the optical system, the light focused at the focal point diffuses before irradiating the surface of the image source, and the energy density is reduced, thereby effectively avoiding the problem of excessive temperature of the image source.

[0066] In the embodiment of the present application, the diffusion angle α of the image light emitted by the image transmission component 20 can be determined according to the display effect and the size of the virtual image. In some examples, the diffusion angle α can be greater than the diffusion angle of the image light emitted by the image source and less than or equal to 60 degrees.

[0067] Optionally, for the image light emitted by the image transmission component 20, the diffusion angle in the horizontal direction may be equal to or different from the diffusion angle in the vertical direction. In some examples, the diffusion angle in the horizontal direction is greater than the diffusion angle in the vertical direction. For example, the diffusion angle in the horizontal direction is 20°, and the diffusion angle in the vertical direction is 15°.

[0068] Optionally, the value range of D is between 1 cm and 50 cm, for example, between 5 cm and 40 cm. In practical applications, it is difficult to ensure that the change value of the diffusion angle of the image light during the translation transmission process is 0, that is, the diffusion angle of the image light will change during the translation transmission process, resulting in a decrease in the display effect. Therefore, the value of D should not be too large. If the value of D is too small, the distance between the image source and the focus of the optical system may be smaller, resulting in a decrease in the effect of suppressing the temperature of the image source. In addition, when the image translation medium is made of solid medium, the larger the D, the larger the volume of the image translation medium, and the larger the weight, which will cause the weight of the display device to be too large. Therefore, the value of D can be determined by comprehensively considering the cost, weight and display effect of the display device.

[0069] Optionally, the sum of the distance D between the image source 10 and the light emitting surface 20a and the distance Z1 between the light emitting surface 20a and the optical component 30 and the effective focal length f of the optical system EL The difference may be between 10 cm and 100 cm. Optionally, the difference may be between 20 cm and 80 cm, such as between 20 cm and 40 cm.

[0070] In some examples, D is equal to 30 cm, Z1 is equal to 35 cm, and f EL is 40cm.

[0071] Figure 4 is a schematic diagram of the structure of a display device provided in an embodiment of the present application. Figure 4 As shown, the display device includes an image source 10, an image transmission component 20 and an optical component 30. The image source 10 is used to emit image light. The image transmission component 20 is used to translate and transmit the image light emitted by the image source 10 to the light emitting surface 20a of the image transmission component 20, and diffuse and transmit the image light emitted by the light emitting surface 20a to the optical component 30. The optical component 30 is used to reflect the image light to the windshield, so that the image light forms a virtual image through the windshield.

[0072] Exemplarily, the image transmission component 20 includes a diffuser 22 and an image translation medium 21, wherein the image translation medium 21 is located between the image source 10 and the diffuser 22, and the image translation medium 21 is used to translate the image light to the light emitting surface 20a. The light emitting surface 20a is the side of the diffuser 22 close to the optical component 30.

[0073] Exemplarily, the image translation medium 21 is a uniform medium. The uniform medium is easy to obtain, which is beneficial to the realization of the display device.

[0074] In order to reduce the impact on the system light effect, the image shifting medium 21 has a relatively large transmittance, for example, above 90%, or even above 95%. Here, transmittance may refer to the transmittance of visible light, so that most of the image light emitted by the image source 10 can pass through the image shifting medium 21.

[0075] Optionally, the refractive index of the homogeneous medium 21 is 1 to 2, for example, 1 to 1.6. When the image light passes through the homogeneous medium with a refractive index within this range, the diffusion angle remains substantially unchanged.

[0076] In a possible implementation, the uniform medium 21 may be a gaseous medium, such as air, etc. This implementation is conducive to simplifying the internal structure of the display device and reducing costs.

[0077] In another possible implementation, the homogeneous medium 21 may be a solid medium, such as glass.

[0078] The diffuser 22 is also called an optical diffuser screen, and can diffuse the image light passing through the image translation medium 21 , and output the diffused image light to the optical component 30 at a diffusion angle α.

[0079] Due to the low cost and high reliability of LCD, it is widely used in display devices. The structure of the display device will be further described below by taking LCD as an image source 10. The LCD includes a backlight source 11 and a liquid crystal display panel 12. The backlight source 11 provides backlight, and the liquid crystal display panel 12 controls the intensity of each pixel through which the backlight passes, thereby realizing image display.

[0080] In this embodiment, since the image translation medium 21 is a uniform medium, the diffusion angle of the image light emitted by the LCD remains basically unchanged when transmitted in the uniform medium. Therefore, the diffusion angle of the image light output by the LCD can be controlled by controlling the collimation angle of the LCD backlight source.

[0081] In the embodiment of the present application, the collimation angle of the backlight source 11 is 0° to 5°. Here, the collimation angle of the backlight source 11 refers to the diffusion angle of the backlight provided by the backlight source. Exemplarily, the collimation angle of the backlight source 11 is 0° to 3°, for example, 0.5 degrees or 1 degree or 2 degrees. The collimation angle of the backlight source 11 is small, so that the image light emitted by the image source is basically moved in parallel from the image source to the light emitting surface of the image transmission component.

[0082] The embodiment of the present application does not limit the type of the light emitting device in the backlight source 11, which may be an LED, a laser, etc.

[0083] The embodiment of the present application does not limit the size of the liquid crystal display panel, which can be determined according to factors such as the magnification of the optical component and the size of the target virtual image. Exemplarily, the size of the liquid crystal display panel can be 3 to 6 inches, for example, 4.5 inches. Here, the size of the liquid crystal display panel can refer to the area of ​​the display region of the liquid crystal display panel or the area of ​​the display surface of the liquid crystal display panel.

[0084] Figure 5 is a schematic diagram of the structure of another display device provided in an embodiment of the present application. Figure 5 As shown, the display device and Figure 4 The structures of the display devices shown are basically the same, except that: Figure 5 The display device further includes a three-dimensional display device 40.

[0085] The three-dimensional display device 40 is located between the image transmission component 20 and the optical component 30. For example, the three-dimensional display device 40 contacts the light-emitting surface of the diffuser 22. The image light emitted by the diffuser 22 passes through the three-dimensional display device 40 and then reaches the optical component 30. The three-dimensional display device 40 is arranged between the image transmission component 20 and the optical component 30, so that the display of the three-dimensional image can be realized without adversely affecting the translation transmission of the image light.

[0086] In a possible implementation, the three-dimensional display device 40 may include a cylindrical lens array. The cylindrical lens array includes a plurality of cylindrical lenses arranged in parallel. By utilizing the refraction of light by the cylindrical lenses, two different parallax images (i.e., the left eye view and the right eye view) are respectively transmitted to both eyes, so that the left eye and the right eye see different images, thereby allowing the viewer to see a three-dimensional image.

[0087] In another possible implementation, the three-dimensional display device 40 includes a parallax barrier, which is used to generate a plurality of stripes of light and dark. When the display device performs three-dimensional display, the image that should be seen by the left eye enters the left eye through the light-transmitting area of ​​the parallax barrier, while the opaque area of ​​the parallax barrier blocks the right eye; similarly, the image that should be seen by the right eye enters the right eye through the light-transmitting area of ​​the parallax barrier, while the opaque area of ​​the parallax barrier blocks the left eye. By separating the images seen by the left eye and the right eye, the viewer can see a three-dimensional image.

[0088] Optionally, the parallax barrier may include a switch liquid crystal screen and a polarizing film sequentially stacked on the light exit surface.

[0089] Figure 6 is a schematic diagram of the structure of another display device provided in an embodiment of the present application. Figure 6 As shown, the display device and Figure 4The difference between the display devices shown is that the structure of the image transmission component is different. Figure 6 As shown, the image transmission component 20 includes an optical fiber array, which includes a plurality of optical fibers 23 arranged in an array.

[0090] The image source 10 includes a plurality of sub-pixels arranged in an array. The plurality of sub-pixels are divided into a plurality of sub-pixel groups, each of which constitutes a pixel. Each pixel includes sub-pixels of multiple colors, for example, a red sub-pixel, a blue sub-pixel, and a green sub-pixel.

[0091] The shape of each sub-pixel includes but is not limited to circle, rectangle, square, diamond, irregular shape and the like. Figure 7 , the sub-pixel is illustrated as a rectangle. For example, the width w of the sub-pixel may be 5 μm to 50 μm, such as 5 μm, 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm or 50 μm.

[0092] The light emitted by each sub-pixel is transmitted through at least one of the multiple optical fibers. That is, each sub-pixel corresponds to one or more optical fibers, and each sub-pixel is used to transmit the light emitted by the sub-pixel to the light-emitting surface of the image transmission component through the corresponding optical fiber. The light emitted by different sub-pixels passes through different optical fibers.

[0093] The propagation of light in optical fiber depends on the total reflection of light in the optical fiber. When image light propagates in the optical fiber, light with an incident angle greater than the total reflection angle cannot pass through the optical fiber. Therefore, the properties of the optical fiber can be used to suppress the change in the diffusion angle of the image light and realize the translational transmission of the image light.

[0094] Here, the orthographic projection of each optical fiber on the surface of the image source is located within the light-emitting area of ​​the corresponding sub-pixel. The aperture of each optical fiber 23 is smaller than the width of the corresponding sub-pixel in the image source 10. The width of a sub-pixel refers to the size in the row direction or column direction of the multiple sub-pixels arranged in the array. In this way, it can be ensured that multiple optical fibers are arranged corresponding to the light-emitting area of ​​each sub-pixel.

[0095] In some examples, the ratio of the sum of the cross-sectional areas of the plurality of optical fibers through which the light emitted by each sub-pixel passes to the light emitting area of ​​the sub-pixel is 70% to 90%. When this condition is met, the light emitted by each sub-pixel can be transmitted through the corresponding optical fiber as much as possible, which is conducive to improving the light efficiency.

[0096] During implementation, for each sub-pixel, the corresponding multiple optical fibers are evenly arranged in the light-emitting area to restore the shape of the sub-pixel as much as possible, thereby improving the image display quality.

[0097] Figure 7 Schematic diagram of the relationship between sub-pixels and optical fibers in the embodiment of the present application. Figure 7 As shown, the width w of the sub-pixel 10a is greater than the diameter p of the optical fiber 23. For example, Figure 7 In the example, the width w of the sub-pixel 10 a is greater than twice the diameter p of the optical fiber 23 .

[0098] Optionally, the numerical aperture of each optical fiber 23 is greater than or equal to the sine value of half the diffusion angle of the image light, and the numerical aperture of the optical fiber is less than the sine value of half the focusing angle of the external ambient light after entering the display device.

[0099] That is, the diameter of the optical fiber 23 satisfies the following formula (3):

[0100]

[0101] In formula (3), NA represents the numerical aperture of the optical fiber, θ1 represents the diffusion angle of the image light, that is, the collimation angle of the backlight source, and θ2 represents the focusing angle of the external ambient light after entering the display device.

[0102] Thus, when the image light is incident from the first end of the optical fiber 23 to the inside of the optical fiber 23, it is totally reflected inside the optical fiber 23 and is transmitted to the second end of the optical fiber 23. When the external ambient light irradiates the second end of the optical fiber 23, it cannot be totally reflected inside the optical fiber due to the large focusing angle and is transmitted from the corresponding optical fiber, thereby reducing the energy density.

[0103] The simulation was performed with θ1 equal to 20°, NA equal to 0.173, and θ2 equal to 60°, and it was verified that this embodiment can reduce the light intensity focused on the image source to K times the original light intensity (i.e., the light intensity focused on the image source in a display device without an image transmission component).

[0104] Here K is calculated according to formula (4):

[0105]

[0106] In this example, the image light emitted by the image source 10 is collimated light, and the diffusion angle is 0° to 40°. Since the optical fiber 23 suppresses the change of the diffusion angle of the image light, the collimation degree of the image light is relatively low. The diffusion angle of the image light can be made relatively large, for example, 5° to 30°. In some examples, the diffusion angle of the image light emitted by the image source 10 is 10° to 25°.

[0107] Figure 8 is a schematic diagram of the structure of another display device provided in an embodiment of the present application. Figure 8 As shown, the display device and Figure 7 The structures of the display devices shown are basically the same, except that: Figure 8The display device in the embodiment further includes: a three-dimensional display device 40. For the relevant content of the three-dimensional display device, please refer to Figure 3 The detailed description of the embodiment shown is omitted here.

[0108] Fig. 9 is a circuit diagram of a display device provided in an embodiment of the present application. Fig. 9 As shown, the circuit in the display device mainly includes a host CPU 1401, an external memory interface 1402, an internal memory 1403, an audio module 1404, a video module 1405, a power module 1406, a wireless communication module 1407, an I / O interface 1408, a video interface 1409, and a display circuit 1410. Among them, the host processor 1401 and its peripheral components, such as the external memory interface 1402, the internal memory 1403, the audio module 1404, the video module 1405, the power module 1406, the wireless communication module 1407, the I / O interface 1408, the video interface 1409, and the display circuit 1410 can be connected through a bus. The host processor 1401 can be called a front-end processor.

[0109] In addition, the circuit diagrams shown in the embodiments of the present application do not constitute a specific limitation on the display device. In other embodiments of the present application, the display device may include more or fewer components than shown in the figure, or combine certain components, or split certain components, or arrange the components differently. The components shown in the figure may be implemented in hardware, software, or a combination of software and hardware.

[0110] The main processor 1401 includes one or more processing units, for example, the main processor 1401 may include an application processor (AP), a modem processor, a graphics processor (GPU), an image signal processor (ISP), a controller, a video codec, a digital signal processor (DSP), a baseband processor, and / or a neural-network processing unit (NPU), etc. Different processing units may be independent devices or integrated into one or more processors.

[0111] The main processor 1401 may also be provided with a memory for storing computer instructions and data. In some embodiments, the memory in the main processor 1401 is a cache memory. The memory may store instructions or data that the main processor 1401 has just used or circulated. If the main processor 1401 needs to use the instruction or data again, it may be directly called from the memory. This avoids repeated access, reduces the waiting time of the main processor 1401, and thus improves the efficiency of the system.

[0112] In some embodiments, the display device may further include a plurality of input / output (I / O) interfaces 1408 connected to the main processor 1401. The I / O interface 1408 may include an inter-integrated circuit (I2C) interface, an inter-integrated circuit sound (I2S) interface, a pulse code modulation (PCM) interface, a universal asynchronous receiver / transmitter (UART) interface, a mobile industry processor interface (MIPI), a general-purpose input / output (GPIO) interface, a subscriber identity module (SIM) interface, and / or a universal serial bus (USB) interface, etc. The above-mentioned I / O interface 1408 may be connected to devices such as a mouse, a touchpad, a keyboard, a camera, a speaker / speaker, a microphone, etc., or may be a physical button on the display device (such as a volume button, a brightness adjustment button, a power button, etc.).

[0113] The external memory interface 1402 can be used to connect an external memory card, such as a Micro SD card, to expand the storage capacity of the display device. The external memory card communicates with the main processor 1401 through the external memory interface 1402 to implement a data storage function.

[0114] The internal memory 1403 can be used to store computer executable program codes, which include instructions. The internal memory 1403 may include a program storage area and a data storage area. Among them, the program storage area may store an operating system, an application required for at least one function (such as a call function, a time setting function, etc.), etc. The data storage area may store data created during the use of the display device (such as a phone book, world time, etc.), etc. In addition, the internal memory 1403 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, a universal flash storage (UFS), etc. The main processor 1401 executes various functional applications and data processing of the display device by running instructions stored in the internal memory 1403 and / or instructions stored in a memory provided in the main processor 1401.

[0115] The display device can implement audio functions such as music playing and calls through the audio module 1404 and the application processor.

[0116] The audio module 1404 is used to convert digital audio information into analog audio signal output, and is also used to convert analog audio input into digital audio signal. The audio module 1404 can also be used to encode and decode audio signals, such as playing or recording. In some embodiments, the audio module 1404 can be arranged in the main processor 1401, or some functional modules of the audio module 1404 can be arranged in the main processor 1401.

[0117] The video interface 1409 can receive external audio and video signals, which can be specifically a high definition multimedia interface (HDMI), a digital visual interface (DVI), a video graphics array (VGA), a display port (DP), etc. The video interface 1409 can also output video to the outside. When the display device is used as a head-up display, the video interface 1409 can receive speed signals and power signals input from peripheral devices, and can also receive external AR video signals. When the display device is used as a desktop display device, the video interface 1409 can receive video signals input from an external computer or terminal device.

[0118] The video module 1405 can decode the video input by the video interface 1409, for example, by performing H.264 decoding. The video module can also encode the video collected by the display device, for example, by performing H.264 encoding on the video collected by the external camera. In addition, the main processor 1401 can also decode the video input by the video interface 1409, and then output the decoded image signal to the display circuit 1410.

[0119] The display circuit 1410 is used to drive the image generation unit to display the corresponding image. In this embodiment, the video interface 1409 receives an external input video source signal, and the video module 1405 decodes and / or digitally processes and outputs one or more image signals to the display circuit 1410. The display circuit 1410 drives the image generation unit to perform imaging according to the input image signal, and then outputs imaging light. In addition, the main processor 1401 can also output an image signal to the display circuit 1410. In addition, the display circuit 1410 can also drive the image generation unit to display an interactive image according to the input image signal.

[0120] The processor 1401 can control the image generation unit to display an image by executing computer instructions.

[0121] The power module 1406 is used to provide power to the main processor 1401 and the image generation unit according to input power (such as direct current). The power module 1406 may include a rechargeable battery, which can provide power to the main processor 1401 and the image generation unit.

[0122] The wireless communication module 1407 can enable the display device to communicate wirelessly with the outside world, and can provide wireless local area networks (WLAN) (such as wireless fidelity (Wi-Fi) networks), Bluetooth (BT), global navigation satellite system (GNSS), frequency modulation (FM), near field communication (NFC), infrared (IR) and other wireless communication solutions. The wireless communication module 1407 can be one or more devices integrating at least one communication processing module. The wireless communication module 1407 receives electromagnetic waves via an antenna, modulates the frequency of the electromagnetic wave signal and performs filtering, and sends the processed signal to the main processor 1401. The wireless communication module 1407 can also receive the signal to be sent from the main processor 1401, modulate the frequency of the signal, amplify it, and convert it into electromagnetic waves for radiation through the antenna.

[0123] In addition, in addition to being input through the video interface 1409, the video data decoded by the video module 1405 can also be wirelessly received through the wireless communication module 1407 or read from an external memory. For example, the display device can receive video data from a terminal device or an in-vehicle entertainment system through the wireless local area network in the vehicle, and the display device can also read audio and video data stored in an external memory.

[0124] An embodiment of the present application also provides a vehicle, which includes any of the aforementioned display devices.

[0125] Fig.10 This is a functional schematic diagram of a transportation tool provided in an embodiment of the present application. Fig.10 The vehicle may include various subsystems, such as the sensor system 21, the control system 22, one or more peripheral devices 23 (one is shown as an example), the power supply 24, the computer system 25 and the display system 26 shown in the figure, and the above subsystems can communicate with each other. The display system 22 may include the display device provided in the embodiment of the present application. The vehicle may also include other functional systems, such as an engine system that provides power for the vehicle, a cockpit, etc., which are not limited in the present application.

[0126] The sensor system 21 may include a number of detection devices, which can sense the information being measured and convert the sensed information into electrical signals or other required forms of information output according to certain rules. Fig.10 As shown, these detection devices may include a global positioning system (GPS), a vehicle speed sensor, an inertial measurement unit (IMU), a radar unit, a laser rangefinder, a camera device, a wheel speed sensor, a steering sensor, a gear sensor, or other elements used for automatic detection, etc., but this application does not limit this.

[0127] The control system 22 may include several components, such as the steering unit, brake unit, lighting system, automatic driving system, map navigation system, network timing system and obstacle avoidance system shown in the figure. The control system 22 may receive information (such as vehicle speed, vehicle distance, etc.) sent by the sensor system 21 to realize functions such as automatic driving and map navigation.

[0128] Optionally, the control system 14 may also include components such as a throttle controller and an engine controller for controlling the vehicle's speed, which is not limited in the present application.

[0129] The peripheral device 23 may include several components, such as a communication system, a touch screen, a user interface, a microphone, and a speaker. The communication system is used to realize network communication between the vehicle and other devices other than the vehicle. In practical applications, the communication system may use wireless communication technology or wired communication technology to realize network communication between the vehicle and other devices. The wired communication technology may refer to communication between the vehicle and other devices through a network cable or optical fiber.

[0130] The power source 24 represents a system that provides power or energy for the vehicle, which may include but is not limited to a rechargeable lithium battery or a lead-acid battery, etc. In practical applications, one or more battery components in the power source are used to provide power or energy for starting the vehicle, and the type and material of the power source are not limited in this application.

[0131] Several functions of the vehicle can be controlled and implemented by the computer system 25. The computer system 25 may include one or more processors 2501 (one processor is shown as an example in the figure) and a memory 2502 (also referred to as a storage device). In actual applications, the memory 2502 is also inside the computer system 25, or it can be outside the computer system 25, for example, as a cache in the vehicle, etc., which is not limited in this application.

[0132] The processor 2501 may include one or more general-purpose processors, such as a graphics processing unit (GPU). The processor 2501 may be used to run the relevant programs or instructions corresponding to the programs stored in the memory 2502 to implement the corresponding functions of the vehicle.

[0133] The memory 2502 may include a volatile memory, such as a RAM; the memory may also include a non-volatile memory, such as a ROM, a flash memory, a HDD, or a solid-state drive SSD; the memory 2502 may also include a combination of the above-mentioned types of memory. The memory 2502 may be used to store a set of program codes or instructions corresponding to the program codes, so that the processor 2501 can call the program codes or instructions stored in the memory 2502 to implement the corresponding functions of the vehicle. In the present application, a set of program codes for vehicle control may be stored in the memory 2502, and the processor 2501 may call the program codes to control the safe driving of the vehicle. How to achieve safe driving of the vehicle is described in detail below in this application.

[0134] Optionally, in addition to storing program codes or instructions, the memory 2502 may also store information such as road maps, driving routes, sensor data, etc. The computer system 25 may be combined with other elements in the vehicle functional framework diagram, such as sensors in the sensor system, GPS, etc., to implement relevant functions of the vehicle. For example, the computer system 25 may control the driving direction or driving speed of the vehicle based on the data input from the sensor system 21, which is not limited in this application.

[0135] The display system 26 can interact with other systems in the vehicle, for example, it can display navigation information sent by the control system 22, or play videos sent by the computer system 25 and the peripheral device 23. The specific structure of the display system 26 refers to the embodiment of the above-mentioned display device, which will not be repeated here.

[0136] Among them, the four subsystems illustrated in the present embodiment, the sensor system 21, the control system 22, the computer system 25 and the display system 26 are only examples and do not constitute a limitation. In practical applications, a vehicle can combine several components in the vehicle according to different functions to obtain subsystems with corresponding different functions. In practical applications, a vehicle may include more or fewer subsystems or components, which is not limited in this application.

[0137] The means of transportation in the embodiments of the present application may be known means of transportation such as cars, airplanes, ships, rockets, etc., or may be new means of transportation that will appear in the future. The car may be an electric car, a fuel car, or a hybrid car, for example, a pure electric car, an extended-range electric car, a hybrid electric car, a fuel cell car, a new energy car, etc., and the present application does not make specific limitations on this.

[0138] Unless otherwise defined, the technical or scientific terms used herein shall have the usual meanings understood by persons with ordinary skills in the field to which the present disclosure belongs. The words "first", "second", "third" and similar words used in the patent application specification and claims of the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one" or "a" do not indicate a quantity limitation, but indicate the existence of at least one.

[0139] The above description is only an embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made on the basis of the present application shall be included in the protection scope of the present application.

Claims

1. A display device, characterized in that: The display device includes an image source, an image transmission component and an optical component. The image source is used to emit image light; The image transmission component is used to translate and transmit the image light emitted by the image source to the light emitting surface of the image transmission component, and diffuse and transmit the image light emitted by the light emitting surface to the optical component; The optical component is used for reflecting the image light to a windshield, so that the image light forms a virtual image through the windshield.

2. The display device according to claim 1, characterized in that The sum of the distance between the image source and the light emitting surface and the distance between the light emitting surface and the optical component is greater than the effective focal length of an optical system, and the optical system includes the optical component and the windshield.

3. The display device according to claim 1 or 2, characterized in that: The image transmission component includes a diffuser and an image translation medium, wherein the image translation medium is located between the image source and the diffuser, the light emitting surface is the side of the diffuser close to the optical component, and the image translation medium is used to translate and transmit the image light to the light emitting surface.

4. The display device according to claim 3, characterized in that: The image translating medium comprises a uniform medium.

5. The display device according to claim 4, characterized in that: The refractive index of the homogeneous medium is 1-2.

6. The display device according to claim 1 or 2, characterized in that: The image source includes a plurality of sub-pixels arranged in an array; The image transmission component includes an optical fiber array, and the optical fiber array includes a plurality of optical fibers arranged in an array; Light emitted by any sub-pixel among the plurality of sub-pixels is transmitted through at least one optical fiber among the plurality of optical fibers.

7. The display device according to claim 6, characterized in that: The numerical aperture of the optical fiber is greater than or equal to the sine value of half the diffusion angle of the image light emitted by the image source, and the numerical aperture of the optical fiber is less than the sine value of half the focusing angle of the external ambient light after entering the display device.

8. The display device according to claim 6 or 7, characterized in that The ratio of the sum of the cross-sectional areas of the plurality of optical fibers through which the light emitted by any sub-pixel passes to the light emitting area of ​​any sub-pixel is 70% to 90%.

9. The display device according to any one of claims 1 to 8, characterized in that: The display device further comprises a three-dimensional display device, and the three-dimensional display device is located between the light emitting surface of the image transmission component and the optical component.

10. The display device according to claim 9, characterized in that: The three-dimensional display device includes a cylindrical lens array, or a parallax barrier.

11. The display device according to any one of claims 1 to 10, characterized in that: The image source includes any one of a liquid crystal display, an organic light emitting diode (OLED) display and a light emitting diode (LED) display.

12. The display device according to any one of claims 3 to 5, characterized in that: The diffusion angle of the image light emitted by the image source is 0° to 5°.

13. The display device according to claim 6 or 7, characterized in that: The diffusion angle of the image light emitted by the image source is 0° to 40°.

14. The display device according to any one of claims 1 to 13, characterized in that: The diffusion angle of the image light emitted by the light emitting surface is greater than the diffusion angle of the image light emitted by the image source, and is less than or equal to 60 degrees.

15. The display device according to any one of claims 1 to 14, characterized in that: The optical assembly comprises: At least one reflector is used to reflect the image light emitted by the image transmission component to the windshield.

16. A means of transport, characterized in that: The vehicle comprises the display device according to any one of claims 1 to 15, and the display device is installed on the vehicle.

Images