Display device and vehicle

Abstract

The invention relates to the technical field of projection display, in particular to display equipment and a vehicle. According to the invention, by utilizing the characteristic that light rays from backward flowing of sunlight are partially reflected to the image source display surface and partially transmitted to one side of the back surface of the first reflector according to a transmission path determined by the first reflector, the transmitted light rays are received by the light receiving part arranged on one side of the back surface of the first reflector; and the equivalent temperature of the corresponding position of the image source display surface is detected through a temperature sensor on the incident surface of the light receiving part, so that the influence of sunlight of the same source on the surface of the image source is judged. According to the invention, the fineness of temperature monitoring on the surface of the image source can be improved, the temperature of any position on the surface of the image source can be accurately detected, and the capability of positioning extreme temperature generated by backward sunlight is enhanced.

Description

Technical Field

[0001] This application relates to the field of projection display technology, and more particularly to a display device and a vehicle. Background Technology

[0002] HUD (Head-Up Display) is a novel in-vehicle display technology that utilizes reflection from the windshield. Specifically, the HUD display device's optical engine emits display light, which is projected onto the windshield through corresponding optical lenses to create a virtual image, enhancing the display effect against the real world outside. However, in vehicles, HUD displays are mounted on the center console, with the projection window facing the windshield. Sunlight can easily enter the HUD display, causing overheating and potentially damaging components such as the image source, rendering the projection display ineffective. Therefore, HUD displays require internal temperature sensors to monitor temperature rise and implement protective measures when temperatures are high. However, sunlight backflow has a converging characteristic, resulting in uneven temperature distribution on the image source surface. A single temperature sensor near the image source is insufficient to accurately reflect its temperature, while multiple temperature sensors would block the emitted display light, preventing normal projection. Summary of the Invention

[0003] The purpose of this application is to provide a display device and a vehicle that solves the technical problem in the prior art that it is impossible to accurately monitor the internal temperature of the HUD display device and it is difficult to detect the extreme temperature generated on the image source surface by the converging effect of sunlight backflow.

[0004] To solve the above-mentioned technical problems, this application adopts the following technical solution.

[0005] In a first aspect, this application provides a display device, comprising: An optical engine and a first reflecting mirror, the optical engine including an image source that emits display light, the display light being emitted from the display surface of the image source and being reflected at least by the front of the first reflecting mirror before reaching the transparent surface of the projection. A light-receiving part that cooperates with the image source is provided on one side of the back of the first reflector. The incident surface of the light-receiving part is arranged opposite to the back of the first reflector to receive light transmitted from the front of the first reflector. At least one temperature sensor is provided on the incident surface of the light-receiving part. The position of the temperature sensor on the incident surface of the light-receiving part corresponds to the position of the detection point on the display surface of the image source.

[0006] In one alternative embodiment of the first aspect, the transparent surface is the windshield of a vehicle.

[0007] As described above, in the optional embodiment, since the temperature sensor is set on the incident surface of the light-receiving part on one side of the back of the first reflector, it will not block the display light emitted from the image source display surface. At the same time, the sunlight that flows back into the display device has uniformity of light after being reflected and transmitted by the first reflector. Therefore, the temperature detected by the temperature sensor will have a stable mapping relationship with the temperature on the image source display surface, which improves the convenience and accuracy of temperature detection.

[0008] In one optional embodiment of the first aspect, at least one temperature sensor is disposed on the incident surface of the light-receiving portion, and the position of the temperature sensor on the incident surface of the light-receiving portion corresponds to the position of a detection point on the image source display surface, including: The temperature sensor is located at the center of the incident surface of the light-receiving part, corresponding to the detection point located at the center of the image source display surface.

[0009] Based on the above description, an optional implementation can determine the temperature at the center of the image source display surface by using the temperature value detected by the temperature sensor based on the correspondence between the two, thereby indirectly obtaining the most representative temperature in the image source display surface.

[0010] In one optional embodiment of the first aspect, at least one temperature sensor is disposed on the incident surface of the light-receiving portion, and the position of the temperature sensor on the incident surface of the light-receiving portion corresponds to the position of a detection point on the image source display surface, including: A first temperature sensor is provided at a first position on the incident surface of the light-receiving part, and a second temperature sensor is provided at a second position. The first position corresponds to the position of the first detection point on the image source display surface, and the second position corresponds to the position of the second detection point on the image source display surface.

[0011] In one optional embodiment of the first aspect, the first position corresponds to the position of the first detection point on the image source display surface, and the second position corresponds to the position of the second detection point on the image source display surface, including: The temperature of the first detection point is determined based on the first temperature value detected by the first temperature sensor. The temperature of the second detection point is determined based on the second temperature value detected by the second temperature sensor.

[0012] Based on the above description, an optional embodiment utilizes multiple temperature sensors disposed on the incident surface of the light-receiving part to indirectly monitor the temperature at multiple different locations on the image source display surface, thereby improving the precision of temperature monitoring and capturing locations with abnormally high temperatures under uncertain conditions.

[0013] In one alternative embodiment of the first aspect, the optical engine further includes a backlight source that provides brightness to the image source; The step of determining the temperature of the first detection point based on the first temperature value detected by the first temperature sensor includes: The temperature at the first detection point is the sum of an adjustment value determined based on the first temperature value and a backlight temperature rise value determined based on the backlight brightness. Determining the temperature of the second detection point based on the second temperature value detected by the second temperature sensor includes: The temperature at the second detection point is the sum of an adjustment value determined based on the second temperature value and a backlight temperature rise value determined based on the backlight brightness.

[0014] In one alternative embodiment of the first aspect, the brightness of the backlight is determined based on the current driving the backlight.

[0015] In one alternative embodiment of the first aspect, the backlight temperature rise value is determined based on a temperature sensor disposed on the backlight.

[0016] Based on the above description, the optional implementation combines the influence of backlight brightness on the image source display surface temperature to comprehensively predict the actual temperature on the image source display surface, thereby improving the accuracy of temperature detection.

[0017] In an alternative embodiment of the first aspect, the display device further includes a light sensor for directly detecting backsunlight, the light sensor having a sampling frequency greater than that of the temperature sensor.

[0018] In one alternative embodiment of the first aspect, the light sensor is disposed near the transparent surface on which the display light is projected.

[0019] In an alternative embodiment of the first aspect, the light sensor is disposed near the transparent surface where the display light is projected, comprising: The light sensor is located next to the projection window of the display device.

[0020] In one alternative embodiment of the first aspect, the light sensor is disposed between the first reflector and the light-receiving part.

[0021] In an alternative embodiment of the first aspect, the light sensor is disposed between the first reflector and the light-receiving part, comprising: The light sensor is offset from the direction directly opposite the incident surface of the light-receiving part.

[0022] Based on the above description, the optional implementation combines the data collected by the temperature sensor with the data collected by the light sensor to achieve comprehensive analysis, thereby compensating for the detection lag of the temperature sensor and improving the limitations of the light sensor's own detection.

[0023] In one alternative embodiment of the first aspect, the sampling frequency of the light sensor being greater than the sampling frequency of the temperature sensor includes: In response to the light sensor detecting a light value, the temperature of the detection point on the image source display surface is predicted. The temperature of the detection point is also determined by combining the temperature value of the temperature sensor most recently detected by the light sensor.

[0024] Based on the above description, the optional implementation method mainly uses a light sensor. The light sensor adopts a higher frequency sampling period to achieve high-frequency updates of temperature prediction, and uses the collected value of the temperature sensor as a correction parameter for the accuracy of temperature detection.

[0025] In one alternative embodiment of the first aspect, the display device further includes a second reflector, wherein the first reflector is a reflector located near the optical engine, and the second reflector is a reflector located near the transparent surface.

[0026] According to the above description, in an optional embodiment, a light-receiving part is provided on the back of the reflector near the optical engine side to ensure the consistency of the backflow of sunlight received between the incident surface of the light-receiving part and the image source display surface, and to avoid the influence of noise present in the light-receiving part.

[0027] In one alternative embodiment of the first aspect, the front side of the first reflector has a first curved surface shape that meets the requirements of optical path projection, and the back side of the first reflector is provided with a second curved surface shape that is complementary to the first curved surface shape.

[0028] Based on the above description, the optional implementation method ensures the consistency of the corresponding light before and after projection on the first reflector by matching the surface shapes of the front and back sides of the first reflector, and restores the light received by the incident surface of the light-receiving part to be as close as possible to the light received on the image source display surface.

[0029] In an optional embodiment of the first aspect, the provision of a light-receiving portion cooperating with the image source on one side of the back surface of the first reflector includes: The material of the incident surface of the light-receiving part is the same as the material of the image source display surface.

[0030] Based on the above description, the optional embodiment uses the same material as the image source display surface, so that the temperature rise performance of the incident surface of the light receiving part receiving light is similar to that on the image source display surface, thereby improving the accuracy of indirectly determining the temperature on the image source display surface.

[0031] In an optional embodiment of the first aspect, the provision of a light-receiving portion cooperating with the image source on one side of the back surface of the first reflector includes: The size range of the incident surface of the light-receiving part is consistent with the size range of the image source display surface.

[0032] Based on the above description, the optional implementation can adopt a unified coordinate system, and according to the detection point position on the image source display surface, temperature sensors are set on the incident surface of the light-receiving part on an equal basis, thereby enhancing the manageability of temperature detection.

[0033] In an optional embodiment of the first aspect, the provision of a light-receiving portion cooperating with the image source on one side of the back surface of the first reflector includes: The incident surface of the light-receiving part is symmetrically arranged with respect to the first reflector and the image source display surface.

[0034] Based on the above description, the optional implementation can make the distance and angle at which the backflowing sunlight reaches the image source display surface and the incident surface of the light-receiving part consistent by symmetrical arrangement, thereby further improving the consistency of temperature performance between the image source display surface and the incident surface of the light-receiving part.

[0035] Secondly, this application provides a means of transportation that includes the display device described in the first aspect.

[0036] Compared to existing technologies, this application utilizes the characteristic that sunlight entering from behind follows a transmission path determined by a first reflecting mirror, with some light being reflected to the image source display surface and some being transmitted to the back side of the first reflecting mirror. A light-receiving part located on the back side of the first reflecting mirror receives the transmitted light, and a temperature sensor on the incident surface of the light-receiving part detects the equivalent temperature at the corresponding location on the image source display surface, thereby determining the impact of sunlight from the same source on the image source surface. This application can improve the precision of temperature monitoring on the image source surface, accurately detect the temperature at any location on the image source surface, and enhance the ability to locate extreme temperatures caused by sunlight backflow. Attached Figure Description

[0037] To more clearly illustrate the technical solution of this application, the accompanying drawings used in the description of the technical solution will be briefly introduced below. Obviously, the drawings described below are merely some examples recorded in this application, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0038] Figure 1 The following are schematic diagrams of HUD projection displays in some examples of this application.

[0039] Figure 2 This is a schematic diagram showing the light-receiving part of a HUD display device in some examples of this application.

[0040] Figure 3 The following are schematic diagrams of optomechanical structures in some examples of this application.

[0041] Figure 4 This is a schematic diagram showing the light-receiving part of a HUD display device in some examples of this application.

[0042] Figure 5 This is a schematic diagram of the first reflector setting of a HUD display device in some examples of this application.

[0043] Figure 6 This is a schematic diagram showing the temperature relationship between the image source display surface and the incident surface of the light-receiving part in some examples of this application.

[0044] Figure 7 This is a schematic diagram showing the temperature relationship between the image source display surface and the incident surface of the light-receiving part in some examples of this application.

[0045] Figure 8 This is a schematic diagram illustrating the backflow of sunlight onto a HUD display device in some examples of this application.

[0046] Figure 9 This is a schematic diagram of sunlight focusing detection on the image source display surface in some examples of this application.

[0047] Figure 10 This is a schematic diagram of a light sensor and a temperature sensor working together to sample data in some examples of this application.

[0048] Figure 11 The following are schematic diagrams of HUD display device modules in some examples of this application.

[0049] Figure 12 These are schematic diagrams of projection displays in vehicles, as shown in some examples of this application. Detailed Implementation

[0050] The present application will be described in detail below with reference to the accompanying drawings. However, the description is only a few examples recorded in the present application and does not limit the present application. Any changes in structure, method or function made by those skilled in the art based on these examples are included within the protection scope of the present application.

[0051] It should be noted that while the same labels or markers may be used in different examples, these do not represent an absolute structural or functional relationship. Furthermore, the use of terms such as "first," "second," etc., in the examples is merely for descriptive convenience and does not represent an absolute structural or functional distinction, nor should it be interpreted as indicating or implying relative importance or the number of corresponding objects. Unless otherwise specified, "at least one" in the description refers to one or more, and "more than one" refers to two or more.

[0052] Furthermore, when representing features, the character " / " can indicate an OR relationship between related objects. For example, "head-up display" or "head-up display" can be represented as "head-up display" or "head-up display". When representing operations, the character " / " can indicate a division relationship between related objects. For example, magnification M = L / P can be represented as L (virtual image size) divided by P (image source size). Moreover, the "AND / OR" in different examples is merely to describe the relationship between related objects. This relationship can include three cases. For example, a concave mirror and / or a convex mirror can be represented as a concave mirror alone, a convex mirror alone, or both concave and convex mirrors.

[0053] HUD projection displays primarily utilize the principle of optical reflection, reflecting the image light to be displayed through a transparent surface into the viewer's eyes. The human eye can then see the virtual image information by following the reverse direction of the light. Correspondingly, the transparent surface can be a vehicle's windshield, which acts as a display screen to show navigation instructions, vehicle speed, etc. Figure 1As shown, a HUD display device may include at least an optical engine 1, a first reflector 2, and a second reflector 3. The optical engine 1 includes a backlight and an image source (not shown). The backlight is used to provide illumination light and adjust the brightness of the illumination light according to control. For example, the backlight can be an LED (Light Emitting Diode), a laser, etc. Under the illumination light provided by the backlight, the image source adjusts the corresponding display content according to control and projects display light from the surface of the image source. For example, the image source can be an LCD (Liquid Crystal Display), a DMD (Digital Micromirror Devices), a MEMS (Micro-Electro-Mechanical System) micromirror, an LCOS (Liquid Crystal on Silicon), etc. The first reflecting mirror 2 and the second reflecting mirror 3 can project the display light emitted by the optical engine 1 onto the windshield 4, enabling customized optical paths within a small space while meeting different projection display requirements. The first reflecting mirror 2 and the second reflecting mirror 3 can be configured as concave mirrors, convex mirrors, concave lenses, convex lenses, etc., according to optical planning needs, and the surface shape of the lenses can be freeform. Optionally, at least one of the first reflecting mirror 2 and the second reflecting mirror 3 can also be angled to a certain extent, thereby changing the projection position of the display light on the windshield 4 to accommodate viewers of different heights. The display light from the optical engine 1 is ultimately reflected on the windshield 4 of the vehicle to form a virtual image 5. When the human eye 6 observes the virtual image 5 through the windshield 4, it can perceive a certain sense of depth, just like viewing a real object at a specific distance outside the windshield. The virtual image 5 can be navigation instructions, vehicle speed, etc., as described above. It should be added that, depending on the characteristics of different optical engines, HUD display devices can also be equipped with astigmatism filters. In some examples, HUD display devices can also include Fresnel lenses, waveguide optics, diffractive optics, holographic optics, tapered optical fibers, etc.

[0054] Based on the aforementioned optical system, HUD display devices can not only project the display light emitted from the image source onto the vehicle's windshield, but also, due to the reversibility of light, transmit external light to the display device's interior. The magnification of the optical system causes sunlight entering the external environment to be focused, increasing the energy density reaching the image source display surface, ultimately resulting in a significant temperature rise on the display surface. Furthermore, as information presentation demands become increasingly sophisticated, the field of view and imaging distance of HUD display devices are being designed to be larger. This necessitates a larger virtual image display area coupled with a higher magnification optical system, further increasing the pressure on temperature control within the display device and resulting in even greater focusing energy density on the image source display surface. For example, when the sun is strong, external sunlight can easily pass through the optical system of a HUD display device and focus on the image source's display surface. This focusing often leads to uneven temperature rise, causing the focused area of ​​the image source display surface to have a much higher temperature than other areas. Such abnormally extreme temperatures are difficult to locate using conventional temperature detection methods because the image source display surface needs to emit the display light required for projection, and a temperature sensor cannot be directly placed on the image source display surface, as it would obstruct the image. Taking LCD image sources as an example, the highest operating temperature of the best TFT-LCD polarizers is currently 105 degrees Celsius. In the optical system of a display device with high magnification, the returned sunlight will focus on the polarizer and could potentially cause temperatures exceeding 105 degrees Celsius. If this maximum temperature is maintained for a period of time, it will cause irreversible damage to the optical engine, especially the image source. Therefore, in order to achieve projection display using image sources such as TFT-LCDs in high magnification optical systems, it is necessary to focus the sunlight onto a more heat-resistant material (such as a metal base or a light shield) rather than the image source's display surface. This can be achieved by adjusting the optical lenses to change the light transmission path in the optical system. However, the prerequisite for taking the above-mentioned protective measures is to achieve precise monitoring of the temperature of the image source display surface. That is, not only should the detected temperature on the image source display surface be as accurate as possible to match the actual situation, but the temperature of more detection points on the image source display surface should also be detected to accurately locate abnormal temperature distribution. Temperature sensors placed near the image source cannot meet such requirements due to the irregular heat diffusion.In some examples, light sensors are used to indirectly detect the temperature of the image source display surface. However, light sensors measure solar energy density in W / m^2, which is determined by the angle and wavelength of the incident light. During normal projection, due to the difference in the angle of the incident light, the measurement value given by the light sensor fluctuates greatly and has little regularity. It cannot be directly used for monitoring the risk of solar backflow. For example, although the light measurement result is at a low value, the backflow caused by the incident light entering the display device due to the specific angle of the incident light is relatively large, and the image source display surface will also generate abnormally high temperature accordingly.

[0055] In some examples, such as Figure 2 , Figure 3 As shown, in the optical system of the HUD display device, the optical engine 1 includes a backlight 11 and an image source 12, as referenced. Figure 3 The backlight 11 and image source 12 are respectively disposed on the two end faces of the optical engine housing 100. The illumination light emitted from the backlight 11 is transmitted from the internal space formed by the optical engine housing 100 to the incident surface of the image source 12, providing display brightness for the image source 12. For the image source of the LCD, under the illumination light, the image source 12 can emit display light containing a specified image on its display surface. Specifically, this can be achieved by a processor connected to the image source 12 (see details). Figure 11 The backlight 11 emits a display signal corresponding to a specified image, and the image source 12 converts the display signal into a change in the electric field that controls the display. Specifically, the image source 12 includes liquid crystals corresponding to several pixels. The liquid crystals can rotate under the control of the electric field, thereby changing the direction of light travel and the color displayed. When the illumination light emitted by the backlight 11 reaches the image source 12, the rotation direction of the liquid crystals determines the transmission mode of the illumination light, thus producing different images, i.e., emitting display light containing different display information. In some examples, the backlight 11 and the image source 12 can support zone control, that is, the processor can control different areas of the backlight 11 to emit illumination light of different brightness. Correspondingly, the image source 12 can also display the content of different areas according to the zone control of the backlight 11. This can be achieved by the processor controlling the specific electric field change of the liquid crystals in a specific area, presenting different light travel directions and colors in different areas, and the projected content can also achieve more precise brightness control. In some examples, a lens combination can be set between the backlight 11 and the image source 12 to converge and homogenize the illumination light emitted by the backlight 11.

[0056] As described above, besides converting a portion of the illumination light received by the backlight 11 into the display light required for projection, the image source 12 also converts a portion into heat, causing a temperature rise on the display surface of the image source 12. Simultaneously, the temperature rise on the image source display surface may also be caused by external light entering from the backlight, and this external light, unlike the illumination light, is not controllable and is often a major source of damage to the image source. For example... Figure 2As shown, in order to monitor the temperature on the display surface of the image source 12, especially the temperature rise caused by external light, a light-receiving part 13 is provided on the back of the first reflector 2. Its function is to receive a portion of the light transmitted from the first reflector 2, and to estimate the temperature rise of the display surface of the image source 12 by utilizing the effect of the transmitted light on the temperature rise of the incident surface of the light-receiving part 13. Specifically, the first reflector 2 in the optical system mainly reflects the display light emitted from the image source 12 onto the second reflector 3. The display light is further reflected by the second reflector 3, allowing it to reach the windshield 4 and form a virtual image 5 that can be seen by the human eye 6. Thus, the first reflector 2 and the second reflector 3 determine the transmission path within the optical system. Simultaneously, light from outside the windshield 4 can also enter the interior along the projection transmission path; for example, some external light can reach the display surface of the image source 12 through reflection by the first reflector 2. Based on the light transmission mechanism, the first reflector 2 cannot completely reflect all incident external light onto the display surface of the image source 12. Some external light will be transmitted from the front to the back of the first reflector 2. In this example, the incident surface of the light-receiving part 13 is positioned opposite the back of the first reflector 2. This transmitted light will reach the incident surface of the light-receiving part 13. The mechanism by which the light on the incident surface of the light-receiving part 13 generates a temperature rise is the same as the mechanism by which the light reflected onto the display surface of the image source 12 generates a temperature rise. Therefore, a temperature sensor can be placed on the incident surface of the light-receiving part 13 instead of on the display surface of the image source 12. It should be noted that although the external light reaching the display surface of the image source 12 and the external light reaching the incident surface of the light-receiving part 13 originate from the same source, the temperature rise is different because the reflective and transmissive capabilities of the first reflector 2 are different. Furthermore, since the temperature rise is directly proportional to the reflectivity and transmittance—that is, the more light reflected or transmitted, the higher the temperature rise—the first reflector 2 can be considered an attenuator. The input external light will be output to the display surface of the image source 12 and the incident surface of the light-receiving part 13 with different attenuation coefficients. Correspondingly, there will be a stable mapping relationship between the temperature rise on the display surface of the image source 12 and the temperature rise on the incident surface of the light-receiving part 13, such as a fixed ratio. This mapping relationship can be fixed after the materials of the first reflector 2, the display surface of the image source 12, and the incident surface of the light-receiving part 13 are determined. Therefore, knowing this mapping relationship, the temperature on the display surface of the image source 12 can be estimated from the temperature on the incident surface of the light-receiving part 13. Optionally, the materials of the display surface of the image source 12 and the incident surface of the light-receiving part 13 are the same, such as glass. In this case, the change in the mapping relationship mainly depends on the change in the material of the first reflector 2, and the specific mapping relationship can be determined based on the material of the first reflector 2.Specifically, after the first reflector 2 is determined, it can be calibrated in advance. By simulating the transmission of light through the first reflector 2, the temperature is obtained by temperature sensors on the display surface of the image source 12 and the incident surface of the light receiving part 13, and the mapping relationship between them is determined. This is used to estimate the temperature when there is no temperature sensor on the display surface of the image source 12 (i.e. during normal projection display).

[0057] In some examples, such as Figure 4 As shown, the light-receiving part 13 is not only disposed on one side of the back of the first reflector 2, but the incident surface of the light-receiving part 13 is also symmetrically disposed with respect to the first reflector 2 and the display surface of the image source 12. That is, the vertical distance from the light-receiving part 13 to the first reflector 2 is the same as the vertical distance from the image source 12 to the first reflector 2. The surface where the first reflector 2 is located serves as the axis of symmetry, so that the image source 12 and the light-receiving part 13 are respectively located on both sides of the axis of symmetry. The angle of the display surface of the image source 12 is also symmetrical with the angle of the incident surface of the light-receiving part 13. That is, it can be understood that the incident surface of the light-receiving part 13 and the display surface of the image source 12 have the same pose relative to the first reflector 2. This ensures that the angles at which different light rays are incident on the display surface of the image source 12 or the incident surface of the light-receiving part 13 are consistent, resulting in a consistent temperature rise. The difference in temperature rise mainly lies in the incident energy. This allows for pre-calibration of the ratio of reflection to transmission capability of the first reflecting mirror 2. This calibrated parameter can remain within a stable range over a long period, provided the first reflecting mirror remains unchanged, and therefore can be stored in advance and continuously retrieved. Figure 5As shown, in an optional example, the first reflector uses a freeform surface, meaning the front surface 21 of the first reflector adopts a first curved surface shape. This surface shape serves the needs of projection and is designed according to actual projection magnification and optical correction requirements. This design allows the display light reaching the windshield 4 to have a good imaging effect, but it may also affect the light transmitted to the back of the first reflector, causing it to present a different state from the external light directly reflected to the display surface of the image source 12. This difference may lead to different trends in temperature rise. In this example, a second curved surface shape can be used on the back surface 22 of the first reflector. The second curved surface shape is complementary to the first curved surface shape; that is, the front surface 21 and the back surface 22 of the first reflector can be linearly symmetrical. For example, if the front of the first reflector is a concave mirror, then the back of the first reflector is also provided with back-to-back concave mirrors. Optionally, the front surface 21 and the back surface 22 of the first reflector can also be composed of two separate lenses of the same or similar materials. Correspondingly, due to the complementary surface design, the first reflector can be equivalent to a plane lens with a certain attenuation capability in terms of transmission. There will be no distortion in the transmission of light between the incident and outgoing light. For example, parallel incident light will be parallel outgoing light. This can keep the transmitted light and reflected light in the same state. In this way, the light reaching the display surface of the image source 12 and the light reaching the incident surface of the light receiving part 13 will have the same temperature rise effect. This will eliminate the noise factors in the mapping relationship between the two as much as possible, making it as linear as possible and simplifying the calibration difficulty.

[0058] As described above, since the temperature sensor is located on the light-receiving part 13 on the back side of the first reflector 2, it does not obstruct the projected display light on the transmission path. Therefore, multiple temperature sensors can be arbitrarily set on the incident surface of the light-receiving part 13. In some examples, in order to obtain the temperature at different detection point positions on the display surface of the image source 12, temperature sensors can be set at corresponding positions on the incident surface of the light-receiving part 13, as shown in the reference. Figure 4This can be a position symmetrical to the first reflecting mirror 2. The temperature sensor can be a thermistor, a type of metal oxide film resistor, such as PTC (Positive Temperature Coefficient) or NTC (Negative Temperature Coefficient) type. Thermistors are highly sensitive to temperature, and their resistance changes with temperature. They are typically made of metal oxides such as manganese, cobalt, nickel, and copper, using ceramic technology. Taking the NTC type as an example, these metal oxides are completely similar to semiconductor materials such as germanium and silicon in their conductivity. The carrier concentration in the resistive semiconductor material is directly proportional to temperature. That is, when the ambient temperature of the thermistor increases, the excitation of electrons and holes in the resistive semiconductor material increases, the carrier concentration also increases, and the resistance decreases. Conversely, when the ambient temperature of the thermistor decreases, the number of electrons and holes in the resistive semiconductor material decreases, the carrier concentration also decreases, and the resistance increases. The resistance value of the thermistor and the ambient temperature of the thermistor have a one-to-one correspondence. By attaching a thermistor to the incident surface of the light-receiving part 13, the corresponding resistance value can be obtained from the circuit connecting the thermistor. This allows for the calculation of the temperature at the thermistor's attachment point, i.e., the temperature at a specific location on the incident surface of the light-receiving part 13. Furthermore, since the incident surface of the light-receiving part 13 uses a material with a temperature rise similar to that of the display surface of the image source 12, it exhibits the same temperature rise characteristics. Therefore, the temperature change on the incident surface of the light-receiving part 13 will have a consistent temperature change trend with that on the display surface of the image source 12. This allows for the establishment of a correlation between the temperature detected on the incident surface of the light-receiving part 13 and the temperature at a corresponding detection point on the display surface of the image source 12. In this example, the ingenious use of the light-receiving part 13 for temperature detection lies in the fact that regardless of the direction of the sun's angle or the orientation of the vehicle on which the display device is located, the light flux transmitted to the back of the first reflector 2 and the light flux reflected to the display surface of the image source 12 can be directly given by a simple law of reflection and a film material coefficient. For the incident surface of the light-receiving part 13, the focusing energy between it and the focusing energy between the display surface of the image source 12 is only a simple mapping relationship, such as a specific coefficient. The temperature on the incident surface of the light-receiving part 13 can reflect the temperature on the display surface of the image source 12 under the current state, which can be specifically deduced based on a specific coefficient.

[0059] Correspondingly, when the size range of the incident surface of the light-receiving part 13 is consistent with the size range of the display surface of the image source 12, for example, when the incident surface of the light-receiving part 13 adopts the same rectangular shape as the display surface of the image source 12, it can be referred to [reference needed]. Figure 5 The optical path structure ensures that the coordinates of each position on the incident surface of the light-receiving part 13 correspond one-to-one with the coordinates of each position on the display surface of the image source 12. This correspondence can be referenced... Figure 5 The temperature is determined based on the symmetry of the first reflecting mirror. Furthermore, a unified coordinate system can be used on the incident surface of the light-receiving part 13 and the display surface of the image source 12. Positions with the same coordinate value correspond to positions with a specific temperature relationship between them. Thus, when the temperature at a corresponding coordinate on the display surface of the image source 13 needs to be known, the temperature sensor value at that coordinate on the incident surface of the light-receiving part 13 can be used for calculation. In some examples, if it is necessary to monitor the temperature at the center of the display surface of the image source 12, it is not necessary to place a temperature sensor at the center of the display surface of the image source 12 to block the light. Instead, a temperature sensor can be placed at the center of the incident surface of the light-receiving part 13. By adjusting the temperature detected by the temperature sensor on the light-receiving part 13 with a certain coefficient, a more representative temperature at the center of the display surface of the image source 12 can be obtained, resulting in a more accurate temperature estimate. Figure 6 As shown, more temperature sensors can be provided on the incident surface of the light-receiving part 13, thereby enabling the acquisition of temperatures at more detection points on the display surface of the image source 12. Specifically, temperature sensors 131, 132, and 133 are respectively positioned on the left, center, and right sides of the incident surface of the light-receiving part 13. As described above, based on the transmission and reflection characteristics of light on the first reflecting mirror, the position of temperature sensor 131 corresponds to detection point 121 on the display surface of the image source 12, and it can reflect the temperature of detection point 121. Similarly, temperature sensor 132 can reflect the temperature of detection point 122, and temperature sensor 133 can reflect the temperature of detection point 123. The temperatures at detection points 121, 122, and 123 can be determined by calculation based on the temperatures detected by temperature sensors 131, 132, and 133, according to adjustment coefficients. The adjustment coefficient can be a pre-calibrated uniform value, or during calibration, temperature sensors can be set at detection points 121, 122, and 123 respectively. The temperature relationship between the location of temperature sensor 131 and detection point 121, the location of temperature sensor 132 and detection point 122, and the location of temperature sensor 133 and detection point 123 can be compared to determine different adjustment coefficients. Thus, during normal monitoring, different adjustment coefficients can be used for calculations at different detection points.

[0060] In some examples, such as Figure 7 As shown, more temperature sensors can be arranged on the incident surface of the light-receiving part 13. This allows for temperature monitoring at more detection points on the display surface of the image source 12, increasing the density of temperature monitoring. This is because, in practical applications, the focusing position of external light entering the display device and appearing on the display surface of the image source 12 is random. (Refer to...) Figure 6If the focusing point is far from any of the detection points 121, 122, and 123, the estimated temperature will be inaccurate. Figure 7 On the display surface of the image source 12, the detection points are basically densely packed at any position, and the temperature at each position can be determined by using a specific temperature sensor on the incident surface of the light-receiving part 13 and combining it with a pre-calibrated adjustment coefficient. For example... Figure 8 As shown, when sunlight passes through the windshield 4 and reaches the second reflector 3, and is reflected by the second reflector 3 to reach the first reflector, the reflection by the first reflector amplifies the external light and projects most of the energy onto the display surface of the image source 12. The focusing position depends on the sun's altitude, the angle of incidence, and the internal optical system. The first reflector is an optical lens closer to the optical engine 1. In this example, the image source 12 and the light-receiving part 13 are located on opposite sides of the first reflector, possessing equal ability to receive the incoming sunlight. Figure 9 As shown, assuming the light focal point on the display surface of image source 12 is located at the upper left corner, the temperature rise at the upper left corner will be extremely high, far exceeding the temperature at other locations. This will be detected by the temperature sensor within the dashed box on the incident surface of the light receiving part 13. That is, the temperature sensor value within the dashed box will be much higher than the temperature sensor values ​​at other locations. Therefore, not only can the temperature at the focal point be estimated, but also... (See details...) Figure 6 , Figure 7 Furthermore, the position of the focal point on the display surface of the image source 12 can be deduced based on the location of the temperature sensor with the higher detection value. Optionally, in addition to calculating based on the abnormal point temperature sensor with the higher detection value, the detection values ​​of the temperature sensors around the abnormal point temperature sensor will also be combined for comprehensive analysis, and the precise position of the focal point on the display surface of the image source 12 will be adjusted according to the detection values ​​of the surrounding temperature sensors.

[0061] Since the temperature sensor's placement on the incident surface of the light-receiving part 13 does not affect normal projection display, real-time temperature monitoring can be achieved. Furthermore, the temperature change at the corresponding location on the display surface of the image source 12 can be monitored by periodically sampling the temperature sensor's detection values. In more examples, besides determining the temperature on the display surface of the image source 12 using the temperature sensor on the incident surface of the light-receiving part 13, a combination of a temperature sensor on the backlight and / or a temperature sensor on the ribbon cable can be used for comprehensive analysis. The temperature sensor on the backlight can determine the impact of the illumination light emitted from the backlight on the temperature rise of the image source. Optionally, the backlight's temperature rise impact can also be directly determined by the brightness output of the backlight, for example, by the brightness parameters controlled by the processor, such as the current driving the backlight. Correspondingly, if it is necessary to determine the actual temperature of the first detection point on the display surface of the image source 12, the first temperature value detected by the first temperature sensor corresponding to the first detection point on the incident surface of the light-receiving part 13 can be obtained. The temperature of the first detection point can be an adjustment value determined based on the first temperature value (see details...). Figure 6 , Figure 7 The sum of the backlight temperature rise value determined based on the backlight brightness and the temperature of the backlight can be used to determine the temperature at other locations besides the first detection point, in conjunction with the temperature sensors on the incident surface of the light-receiving part 13 and the backlight. In some examples, the temperature sensors on the ribbon cable are generally close to the image source 12. On the one hand, they reflect the temperature diffusion on the display surface of the image source 12 to a certain extent, and the temperature detected by them can be used as the basis for error processing in the above calculation of the display surface temperature of the image source 12. On the other hand, the temperature sensors on the ribbon cable detect the ambient temperature inside the display device, which will also have a certain impact on the temperature rise on the display surface of the image source 12. The influence of the temperature rise can also be appropriately considered when calculating the temperature on the display surface of the image source 12. For example, the detected value can be multiplied by a certain conductivity coefficient and added to the final detection point temperature.

[0062] In some examples, in addition to using a temperature sensor for temperature monitoring, a light sensor can be combined to estimate the amount of sunlight entering the display device. The light sensor can be a photosensitive element, capable of sensitively sensing specific wavelengths of external light and converting light energy into an electrical signal. This means there can be a one-to-one correspondence between the light sensor's collected values ​​and the actual light intensity received. For example, the light sensor could be a specific type of solar sensor. In this example, the light sensor can be positioned along the path of external light entering the display device, such as near the windshield, specifically in the projection window of the display device facing the windshield (see [reference needed]). Figure 12The light sensor acquires different detection values ​​as the intensity of sunlight changes. Specifically, the circuit connected to the photosensitive element obtains the corresponding electrical signal value, thereby determining the corresponding light intensity. In some examples, this is also based on the light transmission characteristics of the first reflecting mirror, referring to... Figure 8 Alternatively, the light sensor 14 can be placed together with the light-receiving part 13 on one side of the back of the first reflector. Considering the attenuation capability of the first reflector, the light intensity detected by the light sensor 14 can also be used to deduce the light intensity before transmission based on a certain adjustment coefficient. This adjustment coefficient can also be obtained through prior calibration. In order to reduce the influence of the placement of the light sensor 14 on the light received by the light-receiving part 13, when the light sensor 13 is placed between the first reflector and the light-receiving part 13, it is offset from the direction opposite to the incident surface of the light-receiving part 13 and the first reflector. At this time, the light sensor will not affect the display light used for projection on the front side of the first reflector, nor will it affect the light transmission on the back side of the first reflector. It can assist in the detection when determining the temperature on the display surface of the image source 12 in real time.

[0063] Accordingly, having both a temperature sensor and a light sensor as detection sources, when estimating the temperature on the display surface of image source 12, the temperature sensor's detection value can be the primary source, with the light sensor's detection value used as an auxiliary source to process errors. Similarly, the light sensor's detection value can be the primary source, with the temperature sensor's detection value used as an auxiliary source to process errors. In some examples, when determining the temperature on the display surface of image source 12, different sampling frequencies can be used based on the different characteristics of the temperature sensor and the light sensor. Since changes in light intensity are more sensitive to changes in sunlight, and temperature sensors on the light-receiving part often have a certain delay in detecting temperature changes, the sampling frequency of the light sensor can be higher than that of the temperature sensor. For example... Figure 10As shown, the light sensor can collect data once every unit of time, while the temperature sensor can collect data once every four unit of time. In this example, the light sensor and temperature sensor can operate on a four-unit-time cycle, ensuring at least one simultaneous detection. During periods when the temperature sensor is not detecting, the light sensor can continuously detect changes in light intensity to estimate the temperature change on the display surface of image source 12. This can be achieved by adjusting the temperature estimate based on the light sensor's detection value from the previous unit of time, or by combining the current light sensor's detection value with the most recent temperature sensor reading. In some examples, the light sensor can also be used as a trigger. By collecting data at a high frequency, the light sensor can detect a sudden and significant change in light intensity, triggering the temperature sensor's detection. The temperature on the display surface of image source 12 can be estimated solely from the temperature sensor's detection value, or by combining the detection values ​​from both the temperature and light sensors, balancing flexibility and accuracy in temperature detection.

[0064] In some examples, after the temperature at a specific location on the image source display surface is indirectly determined by a temperature sensor on the incident surface of the light-receiving part, continuous monitoring of the image source display surface can be achieved. When the temperature at a certain location exceeds a control threshold, such as the maximum tolerable temperature of 105 degrees Celsius, a protection mechanism for the image source will be triggered to prevent permanent damage to the image source at high temperatures. In some examples, the brightness of the backlight can be reduced to decrease the overall temperature rise on the image source display surface. Optionally, the image source display surface can be divided into multiple areas based on the locations of multiple temperature sensors on the incident surface of the light-receiving part, and the brightness management of the backlight will be managed accordingly. When the temperature determined based on a specific temperature sensor exceeds the control threshold, only the backlight brightness of the area corresponding to that specific temperature sensor will be reduced, achieving precise control. In some examples, when the detected temperature exceeds the control threshold, optical lenses, such as a second reflector, can be automatically retracted, that is, the display device temporarily shuts down the projection display, preventing external light from entering the interior and focusing on the image source display surface, directly reducing the impact of sunlight backflow on the temperature rise of the image source display surface. In some examples, fans located inside the display device, such as those on the optical engine housing, can be activated to enhance heat dissipation when the detected temperature exceeds a control threshold.

[0065] When the HUD display device in the above example is applied to an automotive system, it enables precise detection of the temperature of the image source display surface inside the device, allowing for timely location of abnormal temperatures on the image source display surface, while temperature detection does not affect normal projection display. For example, Figure 11As shown, the HUD display device integrated in the vehicle can be powered and fed by the vehicle's infotainment system 92, or it can be powered and generate data by the HUD display device itself. Specifically, the HUD display device may include a processor 91, an Ethernet interface 901, a CAN (Controller Area Network) interface 902, a power management module 903, running memory 904, storage memory 905, a temperature sensor 906, a motor 907, a backlight 908, an image source 909, a positioning module 910, radar 911, and a camera 912, etc. It should be noted that... Figure 11 The modules listed herein are merely illustrative and do not constitute any limitation. In some examples, the HUD display device may also include other modules. Furthermore, the modules described above may be implemented in one or more hardware components in different examples, or a single module may be implemented by a combination of multiple hardware components.

[0066] The processor 91, serving as the control center of the HUD display device, includes one or more processing units of any type, including but not limited to microcontrollers, microcontrollers, DSPs (Digital Signal Processors), or any combination thereof. The processor 91 generates operation control signals according to a computer program to control other modules and cooperate with corresponding modules to process acquired or inherent data and instructions.

[0067] Ethernet interface 901 is a network data connection port for local area network communication. It defines a series of software and hardware standards. Multiple electronic devices can be connected together through Ethernet interface 901. In this example, processor 91 can interact with vehicle infotainment system 92 through Ethernet interface 901, such as sending data to vehicle infotainment system 92 or receiving data sent by vehicle infotainment system 92.

[0068] The CAN interface 902 is a network data connection port for the Controller Area Network (CAN), providing a standard bus for automotive control systems and embedded industrial control systems, enabling communication and interaction between control nodes. In this example, the processor 91 can also interact with the vehicle's infotainment system 92 via the CAN interface 902. Optionally, the processor 91 can also connect to other external devices via the CAN interface 902. In some examples, the processor 91 may also be equipped with a GPIO (General-purpose input / output) interface to improve the compatibility of peripheral connections.

[0069] The power management module 903 is connected to the vehicle head unit 92 and can receive power from the vehicle head unit 92 to provide regulated power to the various modules of the HUD display device, ensuring that the processor 91 and various modules work under normal voltage supply and avoiding damage under overvoltage.

[0070] The running memory 904 is used to store the computer program executed by the processor 91, as well as temporarily stored calculation data and data exchanged with the storage memory. The running memory 904 can be a memory such as SDRAM (Synchronous Dynamic Random-access Memory).

[0071] Storage memory 905 is used to store resources such as display content of the HUD display device, as well as long-term stored running programs and data. Storage memory 905 can be a flash memory or other similar storage device. In some examples, processor 91 may also provide an interface to access external storage.

[0072] Temperature detection 906 is used to detect the internal temperature of the HUD display device. Specifically, it can include several temperature sensors. Since the resistance of the temperature sensors changes with temperature, the processor 91 can determine the resistance value of each temperature sensor at a corresponding temperature based on the voltage change between each temperature sensor and a voltage divider resistor under a fixed power supply voltage, thereby deducing the temperature at the location of the temperature sensor. As mentioned above, the temperature sensors can be located on the back side of the reflector without affecting the normal transmission of display light in the optical system. In some examples, the processor 91 can control several temperature sensors via a GPIO interface. These temperature sensors can be located at different positions inside the HUD display device, and the processor 91 can use time-division multiplexing to acquire the temperature values ​​fed back by each temperature sensor.

[0073] Motor 907, under the control of processor 91, drives the optical lenses in the HUD display device to rotate, thereby changing the corresponding optical path. For example, when sunlight backflow causes the image source surface to heat up, the motor can drive the optical lenses to prevent external sunlight from reaching the image source surface. In some examples, processor 91 can also drive a fan on the HUD display device via motor 907 to increase the speed of air exchange between the inside and outside of the HUD display device for heat dissipation. Specifically, motor 907 is connected to processor 91 through a motor driver chip, which provides high-performance power output to motor 907 and can also communicate and control processor 91 through interfaces such as SPI (Serial Peripheral Interface).

[0074] The backlight 908 provides illumination light and adjusts its brightness according to the control of the processor 91, thereby adjusting the overall projection brightness of the HUD display device. The backlight 908 works in conjunction with the image source 909 to achieve the main functions of optical-engine projection display. The backlight 908 can be an LED (Light Emitting Diode), laser, etc. Specifically, the backlight 908 is connected to the processor 91 through a backlight driver chip. The backlight driver chip provides driving voltage to the backlight 908 and controls its brightness under the pulse width signal output by the processor 91.

[0075] Image source 909 is used to display images of corresponding content and project the display light corresponding to the image according to the control of processor 91. Image source 909 can be LCD (Liquid Crystal Display), DMD (Digital Micromirror Devices), MEMS (Micro-Electro-Mechanical System) micromirrors, LCOS (Liquid Crystal on silicon), etc.

[0076] The positioning module 910 is used to monitor the position of the HUD display device and the corresponding vehicle. The positioning module 910 can be a global navigation satellite system such as GPS (Global Positioning System) or BeiDou Navigation Satellite System. By measuring the distance between the satellite and the receiver on the positioning module 910 at different locations, it determines the corresponding position and orientation data. In some examples, the positioning module 910 may also include an inertial navigation system. Based on Newton's laws of motion, it measures the acceleration of the positioning module 910 in the inertial reference frame, integrates it over time, and transforms it to the navigation coordinate system to obtain data such as velocity, yaw angle, and position in the navigation coordinate system. Optionally, the inertial navigation system can assist the global navigation satellite system in achieving more accurate positioning, providing the processor 91 with the corresponding position information.

[0077] Radar 911 is used to determine the position of a target object by using electromagnetic waves, and can usually determine the distance between the target object and the vehicle where the radar 911 is located.

[0078] Camera 912 includes a vehicle body camera and an in-vehicle camera. The vehicle body camera is used to determine the position of a target object through visual recognition. The vehicle body camera can be a monocular camera or a binocular camera. The biggest difference between a monocular camera and a binocular camera is that a binocular camera can capture images from two different perspectives, thereby obtaining distance information in three-dimensional space. The in-vehicle camera is used to identify the behavioral state of the driver and passengers inside the vehicle, including fatigue detection, distraction detection, facial expression recognition, gesture recognition, and eye tracking. In this example, the in-vehicle camera can also specifically implement eye tracking.

[0079] In some examples, the positioning module 910, radar 911, and camera 912 can be directly connected to the vehicle infotainment system 92, without being directly connected to the processor 91 of the HUD display device. For example, the vehicle infotainment system 92 itself integrates a positioning module for location tracking and radar and cameras for autonomous driving. The HUD display device can obtain the data collected by the positioning module, radar, and camera in real time through communication with the vehicle infotainment system 92.

[0080] like Figure 12 As shown, vehicles can be equipped with the aforementioned HUD display device. Specifically, the HUD display device is integrated inside the center console 10, for example, in front of the steering wheel. The HUD display device projects corresponding display light onto the windshield 4 directly opposite the vehicle through its projection window 102. Viewers inside the cockpit can directly see the corresponding virtual image on the windshield 4. Specifically, the corresponding display area 50 on the windshield 4 includes basic display information (vehicle speed, gear position, etc.) and extended display information (warning information, navigation information, etc.). Drivers can view the content without looking down, improving safety. More importantly, the temperature sensor can monitor internal changes in the display device while projecting, especially by indirectly estimating the actual temperature at a specific location on the image source display surface, promptly detecting potential damage from sunlight backflow. It should be noted that vehicles are not limited to cars as a means of transportation; they can also include buses, trucks, excavators, motorcycles, trains, high-speed trains, ships, yachts, airplanes, spacecraft, etc. The windshield for projection is not limited to the windshield of a car; it can also be a transparent surface in other locations.

[0081] Based on the above examples, the technical solutions involved in this application can be directly embodied in hardware, software modules executed by a control unit, or a combination of both, i.e., one or more steps and / or combinations of one or more steps. These can correspond to various software modules in a computer program flow, or to various hardware modules, such as ASICs (Application Specific Integrated Circuits), FPGAs (Field-Programmable Gate Arrays), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or any suitable combination thereof. For ease of description, the above description divides the functions into various modules and describes them separately. Of course, in implementing this application, the functions of each module can be implemented in one or more software and / or hardware components.

[0082] Through the above description of examples, those skilled in the art can clearly understand that this application can be implemented using software plus the necessary general-purpose hardware platform. Based on this understanding, the technical solution involved in this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This software is executed by a microcontroller unit and, depending on the required configuration, can include one or more microcontroller units of any type, including but not limited to microcontroller units, microcontrollers, DSPs (Digital Signal Processors), or any combination thereof. The software is stored in memory, such as volatile memory (e.g., random access memory), non-volatile memory (e.g., read-only memory, flash memory), or any combination thereof.

[0083] In summary, this application utilizes the characteristic that sunlight entering from behind follows a transmission path determined by the first reflecting mirror, with some light being reflected to the image source display surface and some being transmitted to the back side of the first reflecting mirror. A light-receiving unit located on the back side of the first reflecting mirror receives the transmitted light, and a temperature sensor on the incident surface of the light-receiving unit detects the equivalent temperature at the corresponding location on the image source display surface, thereby determining the impact of sunlight from the same source on the image source surface. This application can improve the precision of temperature monitoring on the image source surface, accurately detect the temperature at any location on the image source surface, and enhance the ability to locate extreme temperatures caused by sunlight backflow.

[0084] It should be understood that although this specification includes some examples, none of these examples constitutes a single, independent technical solution. This descriptive style is merely for clarity. Those skilled in the art should consider this specification as a whole, and the technical solutions in the examples can be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0085] The detailed descriptions listed above are merely specific descriptions of feasible implementation methods of this application and are not intended to limit the scope of protection of this application. All equivalent implementation methods or modifications that do not depart from the teachings of this application should be included within the scope of protection of this application.

Claims

1. A display device, characterized in that, include: An optical engine and a first reflecting mirror, the optical engine including an image source that emits display light, the display light being emitted from the display surface of the image source and being reflected at least by the front of the first reflecting mirror before reaching the transparent surface of the projection. A light-receiving part that cooperates with the image source is provided on one side of the back of the first reflector. The incident surface of the light-receiving part is arranged opposite to the back of the first reflector to receive light transmitted from the front of the first reflector. At least one temperature sensor is provided on the incident surface of the light-receiving part. The position of the temperature sensor on the incident surface of the light-receiving part corresponds to the position of the detection point on the display surface of the image source.

2. The display device according to claim 1, characterized in that, At least one temperature sensor is disposed on the incident surface of the light-receiving part, and the position of the temperature sensor on the incident surface of the light-receiving part corresponds to the position of the detection point on the image source display surface, including: A first temperature sensor is provided at a first position on the incident surface of the light-receiving part, and a second temperature sensor is provided at a second position. The first position corresponds to the position of the first detection point on the image source display surface, and the second position corresponds to the position of the second detection point on the image source display surface.

3. The display device according to claim 2, characterized in that, The first position corresponds to the position of the first detection point on the image source display surface, and the second position corresponds to the position of the second detection point on the image source display surface, including: The temperature of the first detection point is determined based on the first temperature value detected by the first temperature sensor. The temperature of the second detection point is determined based on the second temperature value detected by the second temperature sensor.

4. The display device according to claim 3, characterized in that, The optical engine also includes a backlight source that provides brightness to the image source; The step of determining the temperature of the first detection point based on the first temperature value detected by the first temperature sensor includes: The temperature at the first detection point is the sum of an adjustment value determined based on the first temperature value and a backlight temperature rise value determined based on the backlight brightness. Determining the temperature of the second detection point based on the second temperature value detected by the second temperature sensor includes: The temperature at the second detection point is the sum of an adjustment value determined based on the second temperature value and a backlight temperature rise value determined based on the backlight brightness.

5. The display device according to claim 1, characterized in that, The display device also includes a light sensor for directly detecting backsunlight, the light sensor having a higher sampling frequency than the temperature sensor.

6. The display device according to claim 1, characterized in that, The display device further includes a second reflector, wherein the first reflector is a reflector close to the optical engine, and the second reflector is a reflector close to the transparent surface.

7. The display device according to claim 1, characterized in that, The front of the first reflector has a first curved surface that meets the requirements of optical path projection, and the back of the first reflector is provided with a second curved surface that is complementary to the first curved surface.

8. The display device according to claim 1, characterized in that, The provision of a light-receiving portion on one side of the back of the first reflector to cooperate with the image source includes: The material of the incident surface of the light-receiving part is the same as the material of the image source display surface.

9. The display device according to claim 1, characterized in that, The provision of a light-receiving portion on one side of the back of the first reflector to cooperate with the image source includes: The incident surface of the light-receiving part is symmetrically arranged with respect to the first reflector and the image source display surface.

10. A means of transportation, characterized in that, Includes the display device according to any one of claims 1-9.

Images