Device and method for solving burn-in problem by adjusting focus position of HUD curved mirror

Abstract

The invention belongs to the field of head-up display, and relates to a device for solving burn-in by adjusting the focus position of an HUD curved mirror, the curved mirror is provided with a front surface for display and a back surface opposite to the front surface, and a sensing area is arranged at the position, corresponding to the focus, of the back surface of the curved mirror; the solving device comprises a sensing module, a control system and a deflection mechanism arranged in the vehicle, the deflection mechanism is configured to be a positioning curved mirror, and the sensing module is connected to the deflection mechanism in a positioning mode; the invention further relates to a solving method. The solving method is achieved by adjusting the focus position of the HUD curved mirror to solve the burn-in problem. The solution method comprises the following steps of: 1, setting a temperature safety threshold value in a microprocessor; different from the prior art, through the design of the sensing area corresponding to the focus position on the back surface of the curved mirror, the limitation that a traditional NTC is limited by the layout of a display area is avoided, and the flexibility of sensor arrangement and the directness of temperature measurement are remarkably improved.

Description

Technical Field

[0001] This application relates to the field of head-up display technology, and more specifically, to a device and method for solving screen burn-in by adjusting the focal position of the HUD curved mirror. Background Technology

[0002] HUD (Head-Up Display) technology originated in military aircraft, designed to allow pilots to access critical information without looking down at instruments, thus improving safety. Since General Motors first introduced it to the automotive industry in 1988, the technology has gradually spread from luxury models to mid-range vehicles. Key factors driving this adoption include cost reductions (e.g., the evolution of automotive electronic architectures such as CAN bus simplifies information access) and advancements in display technology (such as TFT-LCD). However, while TFT-based image generation units (PGUs) reduce costs, they also introduce a significant risk of "sunlight backflow." Strong sunlight entering the HUD through the windshield and being focused by freeform concave mirrors can create a high-energy light spot on the TFT screen, similar to a solar cooker. This localized high temperature can easily cause permanent damage to the screen pixels, a phenomenon known as "burn-in." This not only damages the equipment and affects image quality, but in extreme cases, the accumulated heat can also pose a safety hazard.

[0003] To address this issue, traditional protection methods primarily rely on thermistor units (NTCs) for temperature monitoring. The common practice is to attach the NTC to a non-display area on the back of the TFT screen. When the system detects an abnormal temperature rise, it takes control measures, such as adjusting the position of optical components to change the light path, or shutting down the TFT screen to prevent continued overheating. For example, patent application CN200710162892.5, entitled "Temperature Control Device and Temperature Control Method," discloses a largely similar technical solution: a temperature sensor detects the temperature, and then a controller controls the temperature regulator.

[0004] However, this traditional NTC placement method has significant shortcomings. The core problem lies in the discrepancy between the monitoring point location and the actual high-temperature risk point. The focal point formed by the freeform mirror converging sunlight usually falls on the central display area of ​​the TFT screen, while the NTC, in order to avoid image display, is often placed at the edge of the screen or in the non-polarized area. Heat must pass through multiple materials such as polarizer, glass, and liquid crystal layer from the focal point to the NTC sensor. These materials generally have poor thermal conductivity, resulting in low heat transfer efficiency and delayed response. Therefore, the temperature detected by the NTC cannot accurately and quickly reflect the true high temperature of the focal area. There is no linear relationship between the monitoring point and the focal temperature, causing untimely or inaccurate protective actions and failing to effectively prevent screen burn-in.

[0005] Therefore, how to overcome the shortcomings of the existing technology is the subject of this invention. Summary of the Invention

[0006] The technical problem to be solved by the embodiments of this application is that, in order to avoid image display, NTC sensors are often placed at the edge of the screen or in non-polarized areas. Heat needs to pass through multiple materials such as polarizers, glass, and liquid crystal layers to travel from the focal point to the NTC sensor. These materials generally have poor thermal conductivity, resulting in low heat transfer efficiency and delayed response. This leads to a lack of linear relationship between the monitoring point and the focal point temperature, causing untimely protection actions or inaccurate judgments.

[0007] To address the aforementioned technical problems, this application provides a device and method for resolving screen burn-in by adjusting the focal position of the HUD curved mirror, employing the following technical solution: A device for resolving screen burn-in by adjusting the focal position of a HUD curved mirror, wherein the curved mirror has a front surface for display and a back surface opposite to the front surface, and a sensing area is provided on the back surface of the curved mirror at the location of the focal point; the device includes a sensing module, a control system, and a deflection mechanism disposed inside the vehicle, the deflection mechanism being configured to position the curved mirror, and the sensing module being positioned and connected to the deflection mechanism; the sensing module includes multiple thermistor units for sensing temperature, all of which are disposed within the sensing area to divide the sensing area into multiple signal sensing sections; the control system is configured to control the deflection mechanism to deflect the curved mirror by a set angle when one or more thermistor units sense that the temperature of the corresponding signal sensing section exceeds a set temperature threshold.

[0008] In the above solution, the dynamic adjustment of the focal point of the curved mirror can be quickly achieved through the cooperation of the sensing module, control system, and deflection mechanism. This deflects the sunlight focus point away from the high-risk area of ​​the TFT screen, effectively preventing screen burn-in caused by localized high temperatures. Since the thermistor units are directly arranged in the back sensing area corresponding to the focal point, they do not need to penetrate multiple layers of low thermal conductivity materials, significantly improving the real-time performance and accuracy of temperature sensing and ensuring the reliability of protective actions. Simultaneously, the array distribution of multiple thermistor units achieves precise mapping of the temperature field in the focal area, providing accurate thermal distribution data for the control system and further optimizing the deflection angle and response timing. Through the synergistic effect of real-time monitoring and dynamic adjustment, the device can continuously maintain display safety in strong light environments, effectively extending the lifespan of the HUD screen and improving driving safety.

[0009] Specifically, multiple thermistor units located in the sensing area on the back of the curved mirror directly collect the temperature signal of the focal area in real time and feed the data back to the control system. The control system analyzes the temperature distribution of each signal sensing unit according to a preset algorithm to determine whether there is a risk of local overheating. Once the temperature of a certain signal sensing unit exceeds the safety threshold, the deflection mechanism is immediately triggered to drive the curved mirror to rotate slightly, so that the sunlight focal point is quickly moved out of the screen display area.

[0010] Unlike existing technologies, this device uses a sensing area design on the back of a curved mirror corresponding to the focal position, which avoids the limitations of traditional NTCs due to the layout of the display area, and significantly improves the flexibility of sensor placement and the directness of temperature measurement.

[0011] Furthermore, the sensing area is arranged in a straight line; a dividing piece is provided between adjacent signal sensing units to separate each signal sensing unit; Alternatively, the back surface may have recesses forming grooves at the corresponding positions of each signal sensing unit to separate each signal sensing unit.

[0012] In the above scheme, the uniformity of the thermistor unit coverage on the focal path is optimized by the linear arrangement of the sensing area. In order to ensure the continuity of temperature monitoring and the accuracy of response, the physical isolation of the groove or the segment effectively suppresses thermal conduction interference and improves the independence and detection sensitivity of each signal sensing unit.

[0013] It is important to note that the thermistor unit can be an array composed of multiple small thermistors connected in series or parallel. This ensures that even if a single thermistor fails due to partial obstruction or damage, the remaining units can still function normally, guaranteeing system reliability. Furthermore, when the curved mirror deflects, causing the focal point to shift, the thermistors at different positions in the array respond sequentially. This allows the control system to accurately capture the focal point's movement trajectory, enabling continuous dynamic monitoring and preventing the inability to detect temperature information at the changed focal point position after the curved mirror deflects by a certain angle.

[0014] Furthermore, the plurality of thermistor units are arranged in a linear array within the sensing area; Alternatively, the sensing area can be divided into two equal parts along its length, with one part defined as the left side and the other as the right side, and all the thermistor units can be arranged sequentially in the sensing area in a left-right order.

[0015] Two implementation methods are provided for the thermistor unit. The first method uses a linear array arrangement to ensure continuous and uniform temperature sampling along the focal point movement path. The second method arranges the thermistor unit in left and right partitions and establishes orientation recognition logic in the control system. When the thermistor unit on the left or right side detects a temperature rise first, it can determine the deviation of the sunlight incident direction and drive the deflection mechanism to adjust in the corresponding direction, thereby improving the pertinence of the response and the adjustment efficiency.

[0016] The design of Scheme 2 not only allows for the determination of the direction of focus movement but also enables the prediction of changes in the angle of sunlight incidence by comparing the temperatures of the left and right areas, thus allowing for advance adjustments to the curved mirror deflection strategy. This layout improves the system's response speed and control accuracy without increasing the number of sensors, and demonstrates stronger adaptability, especially when dealing with complex lighting environments during vehicle movement.

[0017] Furthermore, the control system includes a multiplexer, a microprocessor, and multiple reference resistors; The multiplexer is electrically connected to the microprocessor; Each of the reference resistors is connected in series with each thermistor unit to form multiple voltage divider circuits, which are connected in parallel between the external power supply and the multiplexer. Each of the reference resistors is further provided with a grounding point and a voltage divider point, which are located at the circuit nodes of the corresponding reference resistor and thermistor unit. Each voltage divider point on the reference resistor is electrically connected to a multiplexer; the microprocessor is configured to sequentially turn on multiple thermistor units via the multiplexer, and to turn on only one voltage divider circuit at any given time to read data from the thermistor unit in that voltage divider circuit.

[0018] With the above design, the microprocessor can sequentially collect the voltage signals of each voltage divider circuit, deduce the actual resistance value of the corresponding thermistor unit by combining the known reference resistor value, and convert it into real-time temperature data based on the resistance-temperature characteristic curve (which can be obtained through multiple experiments, i.e., by conducting experiments in advance to obtain the actual resistance value of the thermistor unit at different temperatures).

[0019] This application also provides a method for solving screen burn-in by adjusting the focal position of the HUD curved mirror, wherein the solution is implemented by a device for solving screen burn-in by adjusting the focal position of the HUD curved mirror; The solutions include: Step 1: Set the temperature safety threshold in the microprocessor; Step 2: The temperature of the corresponding signal sensing unit is sensed in real time by multiple thermistor units and transmitted to the microcontroller; Step 3: The microcontroller compares the actual temperature value fed back by the thermistor unit with the preset temperature safety threshold and calculates the deviation value. Step 4: The microcontroller calculates and generates a control signal based on the deviation value using the PID algorithm, and then converts it into a control command to be output to the deflection mechanism. Step 5: The deflection mechanism guides the curved mirror to reciprocate within a set angle; Step 6: Repeat steps 2 through 5.

[0020] With the above design, a detection-judgment-deflection-re-detection system is formed. This system can dynamically adjust the focal position of the curved mirror, effectively avoiding local high temperature caused by long-term static imaging, thereby suppressing the occurrence of screen burn-in.

[0021] Furthermore, the temperature safety threshold in step 1 includes a first-level warning threshold, a second-level action threshold, and a third-level limit threshold; The first-level warning threshold is configured as the temperature range during the operation of the curved mirror; The secondary action threshold is configured as the temperature at which the deflection mechanism guides the curved mirror to reciprocate within a set angle; The Level 3 limit threshold is configured as the automatic standby temperature for curved mirrors.

[0022] With the above design, the microprocessor has a judgment standard that enables it to make differentiated response decisions based on the real-time temperature range. It can alert potential risks in the initial warning stage, actively drive the deflection mechanism to adjust the focus position when the action threshold is reached to prevent the temperature from rising continuously, and force it to enter standby mode when it approaches the limit threshold to ensure the safety of the device, thereby achieving multi-level gradient protection.

[0023] Furthermore, step 2 specifically includes: Step 201: The microprocessor controls the multiplexer through digital signals according to the preset order of the thermistor units in the sensing area, so that only one voltage divider circuit is turned on at a certain time. Step 202: After the thermistor unit senses the temperature change of the corresponding signal sensing unit, the resistance of the thermistor unit changes in real time, which in turn causes the voltage at the voltage divider point in the connected voltage divider circuit to change, and transmits the voltage signal of the voltage divider circuit to the microprocessor. Step 203: The microprocessor cyclically scans all voltage divider circuits to achieve "real-time" sensing.

[0024] Furthermore, step 3 specifically includes: Step 301: The microprocessor converts the received voltage signal into a digital value through its internal analog-to-digital converter; Step 302: Calculate the current resistance value of the thermistor unit according to the formula R1=R2×(V1 / V2-1), and then convert the current resistance value of the thermistor unit into the current temperature value of the thermistor unit by using the pre-stored thermistor unit resistance value parameter table. Where R1 is the current resistance value of the thermistor unit, R2 is the reference resistance value, V1 is the working power supply voltage value, and V2 is the digital value of the voltage signal of the voltage divider circuit. Step 303: Obtain the deviation value. Deviation value = current temperature value of the thermistor unit - secondary action threshold.

[0025] Furthermore, step 4 specifically includes: Step 401: The microprocessor reads the deviation value calculated in step 3 and runs the PID algorithm to calculate the required angle for rotating the curved mirror. Step 402: The microprocessor converts the calculated angle into a pulse signal and sends it to the deflection mechanism; Step 403: The deflection mechanism executes the deflection command.

[0026] Furthermore, in step 5, the deflection mechanism includes a deflector that executes the deflection command, wherein the deflector is a stepper motor or a voice coil motor. Step 5 involves the following steps: The deflector drives the curved mirror to deflect at a set angle according to the received pulse signal, so that the light focus moves away from the sensitive area of ​​the TFT.

[0027] Furthermore, in step 401, the PID algorithm calculates the set angle based on the deviation value and the required deflection angle formula. The formula for the deviation value and the required deflection angle is: α = 0.15 × Q, Q = (T - T1); Where α is the required deflection angle, Q is the deviation value, T is the current temperature value of the thermistor unit, and T1 is the secondary action threshold.

[0028] Compared with the prior art, the embodiments of this application have the following main advantages: In the above solution, the dynamic adjustment of the focal point of the curved mirror can be quickly achieved through the cooperation of the sensing module, control system, and deflection mechanism. This deflects the sunlight focus point away from the high-risk area of ​​the TFT screen, effectively preventing screen burn-in caused by localized high temperatures. Since the thermistor units are directly arranged in the back sensing area corresponding to the focal point, they do not need to penetrate multiple layers of low thermal conductivity materials, significantly improving the real-time performance and accuracy of temperature sensing and ensuring the reliability of protective actions. Simultaneously, the array distribution of multiple thermistor units achieves precise mapping of the temperature field in the focal area, providing accurate thermal distribution data for the control system and further optimizing the deflection angle and response timing. Through the synergistic effect of real-time monitoring and dynamic adjustment, the device can continuously maintain display safety in strong light environments, effectively extending the lifespan of the HUD screen and improving driving safety.

[0029] Specifically, multiple thermistor units located in the sensing area on the back of the curved mirror directly collect the temperature signal of the focal area in real time and feed the data back to the control system. The control system analyzes the temperature distribution of each signal sensing unit according to a preset algorithm to determine whether there is a risk of local overheating. Once the temperature of a certain signal sensing unit exceeds the safety threshold, the deflection mechanism is immediately triggered to drive the curved mirror to rotate slightly, so that the sunlight focal point is quickly moved out of the screen display area.

[0030] Unlike existing technologies, this device uses a sensing area design on the back of a curved mirror corresponding to the focal position, which avoids the limitations of traditional NTCs due to the layout of the display area, and significantly improves the flexibility of sensor placement and the directness of temperature measurement. Attached Figure Description

[0031] To more clearly illustrate the solution of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 A schematic diagram of the structure of multiple thermistor units arranged in a linear array within the sensing area in an embodiment of the present invention; Figure 2 A schematic diagram of the structure when all the thermistor units in the embodiments provided by the present invention are arranged in the sensing area in a left-right order; Figure 3 A schematic diagram of the curved mirror in operation according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of the thermistor unit connected to the reference resistor in an embodiment of the present invention.

[0033] Reference numerals: 1. Curved mirror; 2. Back side; 3. Sensing area; 4. Sensing module; 5. Thermistor unit; 6. Signal sensing unit; 7. Segmentation piece; 8. Groove; 9. Multiplexer; 10. Microprocessor; 11. Reference resistor. Detailed Implementation

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein in the specification of the application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "comprising" and "having," and any variations thereof, in the specification, claims, and foregoing drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the specification, claims, or foregoing drawings of this application are used to distinguish different objects, not to describe a particular order.

[0035] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0036] like Figures 1-4 As shown, this application embodiment provides a device for solving screen burn-in by adjusting the focal position of a HUD curved mirror 1. The curved mirror 1 has a front surface for display and a back surface 2 opposite to the front surface. A sensing area 3 is provided on the back surface 2 corresponding to the focal position. The device includes a sensing module 4, a control system, and a deflection mechanism installed inside the vehicle. The deflection mechanism is configured to position the curved mirror 1, and the sensing module 4 is positioned and connected to the deflection mechanism. The sensing module 4 includes multiple thermistor units 5 for sensing temperature. All the thermistor units 5 are arranged within the sensing area 3 to divide the sensing area 3 into multiple signal sensing parts 6. The control system is configured to control the deflection mechanism to deflect the curved mirror 1 by a set angle when one or more thermistor units 5 sense that the temperature of the corresponding signal sensing part 6 exceeds a set temperature threshold.

[0037] In the above solution, the dynamic adjustment of the focal position of the curved mirror 1 can be quickly achieved through the cooperation of the sensing module 4, the control system, and the deflection mechanism, so that the sunlight focal point is deviated from the high-risk area of ​​the TFT screen, thereby effectively avoiding screen burn-in caused by local high temperature. Since the thermistor unit 5 is directly arranged on the back side 2 sensing area 3 corresponding to the focal point, it does not need to penetrate multiple layers of low thermal conductivity materials, which significantly improves the real-time performance and accuracy of temperature sensing and ensures the reliability of the protection action. At the same time, the array distribution of multiple thermistor units 5 realizes the accurate mapping of the temperature field in the focal area, providing the control system with accurate heat distribution data, and further optimizing the deflection angle and response timing. Through the synergistic effect of real-time monitoring and dynamic adjustment, the device can continuously maintain display safety in strong light environments, effectively extend the lifespan of the HUD screen, and improve driving safety.

[0038] Specifically, multiple thermistor units 5 located in the sensing area 3 on the back 2 of the curved mirror 1 directly collect the temperature signal of the focal area in real time and feed the data back to the control system. The control system analyzes the temperature distribution of each signal sensing unit 6 according to a preset algorithm to determine whether there is a risk of local overheating. Once the temperature of a certain signal sensing unit 6 exceeds the safety threshold, the deflection mechanism is immediately triggered to drive the curved mirror 1 to rotate slightly, so that the sunlight focal point is quickly moved out of the screen display area.

[0039] Unlike existing technologies, this device uses a sensing area 3 on the back 2 of the curved mirror 1 corresponding to the focal position, which avoids the limitations of traditional NTCs due to the layout of the display area and significantly improves the flexibility of sensor placement and the directness of temperature measurement.

[0040] This application also provides a method for solving screen burn-in by adjusting the focal position of the HUD curved mirror 1, wherein the solution is implemented by a device for solving screen burn-in by adjusting the focal position of the HUD curved mirror 1; The solutions include: Step 1: Set the temperature safety threshold in the microprocessor 10; Step 2: The temperature of the corresponding signal sensing unit 6 is sensed in real time by multiple thermistor units 5 and transmitted to the microcontroller. Step 3: The microcontroller compares the actual temperature value fed back by the thermistor unit 5 with the preset temperature safety threshold and calculates the deviation value. Step 4: The microcontroller calculates and generates a control signal based on the deviation value using the PID algorithm, and then converts it into a control command to be output to the deflection mechanism. Step 5: The deflection mechanism guides the curved mirror 1 to reciprocate within a set angle; Step 6: Repeat steps 2 through 5.

[0041] With the above design, a detection-judgment-deflection-re-detection system is formed. This system can dynamically adjust the focal position of the curved mirror 1, effectively avoid local high temperature caused by long-term static imaging, and thus suppress the occurrence of screen burn-in.

[0042] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.

[0043] Example 1 A device for solving screen burn-in by adjusting the focal position of a HUD curved mirror 1, wherein the curved mirror 1 has a front for display and a back 2 opposite to the front, and a sensing area 3 is provided on the back 2 of the curved mirror 1 at the position corresponding to the focal point; the device includes a sensing module 4, a control system, and a deflection mechanism installed inside the vehicle, the deflection mechanism being configured to position the curved mirror 1, and the sensing module 4 being positioned and connected to the deflection mechanism; the sensing module 4 includes multiple thermistor units 5 for sensing temperature, all of which are arranged within the sensing area 3 to divide the sensing area 3 into multiple signal sensing parts 6; the control system is configured to control the deflection mechanism to deflect the curved mirror 1 by a set angle when one or more thermistor units 5 sense that the temperature of the corresponding signal sensing part 6 exceeds a set temperature threshold.

[0044] In the above solution, the dynamic adjustment of the focal position of the curved mirror 1 can be quickly achieved through the cooperation of the sensing module 4, the control system, and the deflection mechanism, so that the sunlight focal point is deviated from the high-risk area of ​​the TFT screen, thereby effectively avoiding screen burn-in caused by local high temperature. Since the thermistor unit 5 is directly arranged on the back side 2 sensing area 3 corresponding to the focal point, it does not need to penetrate multiple layers of low thermal conductivity materials, which significantly improves the real-time performance and accuracy of temperature sensing and ensures the reliability of the protection action. At the same time, the array distribution of multiple thermistor units 5 realizes the accurate mapping of the temperature field in the focal area, providing the control system with accurate heat distribution data, and further optimizing the deflection angle and response timing. Through the synergistic effect of real-time monitoring and dynamic adjustment, the device can continuously maintain display safety in strong light environments, effectively extend the lifespan of the HUD screen, and improve driving safety.

[0045] Specifically, multiple thermistor units 5 located in the sensing area 3 on the back 2 of the curved mirror 1 directly collect the temperature signal of the focal area in real time and feed the data back to the control system. The control system analyzes the temperature distribution of each signal sensing unit 6 according to a preset algorithm to determine whether there is a risk of local overheating. Once the temperature of a certain signal sensing unit 6 exceeds the safety threshold, the deflection mechanism is immediately triggered to drive the curved mirror 1 to rotate slightly, so that the sunlight focal point is quickly moved out of the screen display area.

[0046] Unlike existing technologies, this device uses a sensing area 3 on the back 2 of the curved mirror 1 corresponding to the focal position, which avoids the limitations of traditional NTCs due to the layout of the display area and significantly improves the flexibility of sensor placement and the directness of temperature measurement.

[0047] Example 2 Furthermore, the sensing area 3 is arranged in a straight line; a dividing piece 7 is provided between adjacent signal sensing units 6 to separate each signal sensing unit 6; Alternatively, the back surface 2 may have recesses 8 at the corresponding positions of each signal sensing part 6 to separate each signal sensing part 6.

[0048] In the above scheme, the uniformity of the coverage of the thermistor unit 5 on the focal path can be optimized by the design of the sensing area 3 arranged in a straight line. In order to ensure the continuity of temperature monitoring and the accuracy of response, the physical isolation of the groove 8 or the dividing plate 7 effectively suppresses heat conduction interference and improves the independence and detection sensitivity of each signal sensing unit 6.

[0049] It is important to note that the thermistor unit 5 can be an array composed of multiple small thermistors connected in series or parallel. This ensures that even if a single thermistor fails due to partial obstruction or damage, the remaining units can still function normally, guaranteeing system reliability. Furthermore, when the curved mirror 1 deflects, causing the focal point to move, the thermistors at different positions in the array respond sequentially. This allows the control system to accurately capture the focal point's movement trajectory, enabling continuous dynamic monitoring and preventing the inability to detect the temperature information at the focal point after the curved mirror 1 has deflected by a certain angle.

[0050] Furthermore, the plurality of thermistor units 5 are arranged in a linear array within the sensing area 3; Alternatively, the sensing area 3 can be divided into two equal parts along its length, with one part defined as the left side and the other as the right side. All the thermistor units 5 are arranged sequentially in the sensing area 3 in a left-right order.

[0051] Two implementation methods are provided for the thermistor unit 5. The first method uses a linear array arrangement to ensure continuous and uniform temperature sampling along the focal point movement path. The second method arranges the thermistor unit in the left and right partitions and establishes orientation recognition logic in the control system. When the left or right thermistor unit 5 detects a temperature rise first, it can determine the deviation of the sunlight incident direction and drive the deflection mechanism to adjust in the corresponding direction, thereby improving the pertinence of the response and the adjustment efficiency.

[0052] By utilizing the design of Scheme 2, it is possible to not only determine the direction of focus movement but also predict the changing trend of the sunlight incident angle by comparing the temperatures of the left and right areas, thereby adjusting the deflection strategy of curved mirror 1 in advance. This layout improves the system's response speed and control accuracy without increasing the number of sensors, and demonstrates stronger adaptability, especially when dealing with complex lighting environments during vehicle movement.

[0053] Furthermore, the control system includes a multiplexer 9, a microprocessor 10, and multiple reference resistors 11; The multiplexer 9 is electrically connected to the microprocessor 10; Each of the reference resistors 11 is connected in series with each thermistor unit 5 to form multiple voltage divider circuits, which are connected in parallel between the external power supply and the multiplexer 9. Each of the reference resistors 11 is also provided with a grounding point and a voltage divider point, which are located at the circuit node of the corresponding reference resistor 11 and the thermistor unit 5. Each voltage divider point on the reference resistor 11 is electrically connected to the multiplexer 9; the microprocessor 10 is configured to sequentially turn on multiple thermistor units 5 through the multiplexer 9, and at any given time only one voltage divider circuit is turned on to read data from the thermistor unit 5 in the voltage divider circuit.

[0054] With the above design, the microprocessor 10 can sequentially collect the voltage signals of each voltage divider circuit, deduce the actual resistance value of the corresponding thermistor unit 5 by combining the known resistance value of the reference resistor 11, and convert it into real-time temperature data according to the resistance-temperature characteristic curve (which can be obtained through multiple experiments, i.e., by conducting experiments in advance to obtain the actual resistance value of the thermistor unit 5 at different temperatures).

[0055] Example 3 This application also provides a method for solving screen burn-in by adjusting the focal position of the HUD curved mirror 1, wherein the solution is implemented by a device for solving screen burn-in by adjusting the focal position of the HUD curved mirror 1; The solutions include: Step 1: Set the temperature safety threshold in the microprocessor 10; Step 2: The temperature of the corresponding signal sensing unit 6 is sensed in real time by multiple thermistor units 5 and transmitted to the microcontroller. Step 3: The microcontroller compares the actual temperature value fed back by the thermistor unit 5 with the preset temperature safety threshold and calculates the deviation value. Step 4: The microcontroller calculates and generates a control signal based on the deviation value using the PID algorithm, and then converts it into a control command to be output to the deflection mechanism. Step 5: The deflection mechanism guides the curved mirror 1 to reciprocate within a set angle; Step 6: Repeat steps 2 through 5.

[0056] With the above design, a detection-judgment-deflection-re-detection system is formed. This system can dynamically adjust the focal position of the curved mirror 1, effectively avoid local high temperature caused by long-term static imaging, and thus suppress the occurrence of screen burn-in.

[0057] Furthermore, the temperature safety threshold in step 1 includes a first-level warning threshold, a second-level action threshold, and a third-level limit threshold; The first-level warning threshold is configured as the temperature range during the operation of the curved mirror 1; The secondary action threshold is configured as the temperature at which the deflection mechanism guides the curved mirror 1 to reciprocate within a set angle; The Level 3 limit threshold is configured as the automatic standby temperature of the curved mirror 1.

[0058] With the above design, the microprocessor 10 has a judgment criterion that enables it to make differentiated response decisions based on the real-time temperature range. It can alert potential risks in the initial warning stage, actively drive the deflection mechanism to adjust the focus position when the action threshold is reached to prevent the temperature from rising continuously, and force it to enter standby mode when it approaches the limit threshold to ensure equipment safety, thereby achieving multi-level gradient protection.

[0059] Specifically, the first-level warning threshold can be selected as less than or equal to 60 degrees Celsius, the second-level action threshold can be selected as 60 to 70 degrees Celsius, and 65 degrees Celsius is generally selected as the calculation benchmark. The third-level extreme threshold can be selected as greater than or equal to 80 degrees Celsius. At the first-level warning threshold, the microprocessor 10 only records the temperature of each thermistor unit 5 and does not take any action, that is, the curved mirror 1 is in working state.

[0060] At the secondary action threshold, the microprocessor 10 determines that the temperature of the focal area of ​​the curved mirror 1 has entered the risk range, and then starts the PID control algorithm to output adjustment commands to the deflection mechanism, driving the curved mirror 1 to swing back and forth at a small angle, so that the imaging spot moves periodically on the windshield, breaking the continuous focusing state of heat energy and effectively dispersing the heat accumulation.

[0061] At the third-level limit threshold, the microprocessor 10 immediately cuts off the main power supply to the HUD, and the curved mirror 1 enters an automatic standby state.

[0062] Furthermore, step 2 specifically includes: Step 201: The microprocessor 10 controls the multiplexer 9 through digital signals according to the preset order of the thermistor units 5 in the sensing area 3, so that only one voltage divider circuit is turned on at a certain time. Step 202: After the thermistor unit 5 senses the temperature change of the corresponding signal sensing unit 6, the resistance value of the thermistor unit 5 changes in real time, which in turn causes the voltage at the voltage divider point in the connected voltage divider circuit to change, and transmits the voltage signal of the voltage divider circuit to the microprocessor 10. Step 203: Microprocessor 10 cyclically scans all voltage divider circuits to achieve "real-time" sensing.

[0063] With the above design, the microprocessor 10 can cyclically scan all voltage divider circuits. In this process, the multiplexer 9 acts like a telephone operator. During operation, the microprocessor 10 commands this "operator": "Activate the first voltage divider circuit on the left." The multiplexer 9 then activates the first voltage divider circuit on the left, at which point only the voltage signal from the first voltage divider circuit on the left can reach the microprocessor 10. After recording this voltage value, the microprocessor 10 commands again: "Activate the first voltage divider circuit on the right," and so on, in a very fast loop (for example, recording all voltage divider circuits within one second). The advantage of this is that it avoids the chaos caused by all voltage divider circuits "speaking" simultaneously (all signals input at the same time), ensuring that each signal is clearly distinguishable.

[0064] Furthermore, step 3 specifically includes: Step 301: The microprocessor 10 converts the received voltage signal into a digital value through its internal analog-to-digital converter; Step 302: Calculate the current resistance value of thermistor unit 5 according to the formula R1=R2×(V1 / V2-1), and then convert the current resistance value of thermistor unit 5 into the current temperature value of thermistor unit 5 by using the pre-stored resistance value parameter table of thermistor unit 5. Where R1 is the current resistance value of thermistor unit 5, R2 is the resistance value of reference resistor 11, V1 is the resistance value of the working power supply voltage, and V2 is the digital value of the voltage signal of the voltage divider circuit. Step 303: Obtain the deviation value. Deviation value = current temperature value of thermistor unit 5 - secondary action threshold.

[0065] With the above design, when the microprocessor 10 detects an anomaly (for example, a thermistor unit 5 detects that the temperature of the corresponding signal sensing unit 6 exceeds 65 degrees Celsius), it first sends the digital value V2 of the measured voltage divider circuit signal to the microprocessor 10 through the multiplexer 9. Then, based on the relationship between the resistance value R2 of the reference resistor 11 and the operating power supply voltage V1, it calculates the actual resistance value R1 of the thermistor using a formula, and converts it to the corresponding temperature value by looking up a table. Finally, it calculates the deviation between the temperature and the secondary action threshold, ensuring that the system can accurately identify the abnormal trend in the early stage of temperature rise, providing a reliable basis for subsequent graded response.

[0066] The specific process for pre-storing the resistance parameter table of thermistor unit 5 is as follows: In a laboratory, a constant temperature bath (such as an ice-water mixture, boiling water, or professional constant temperature equipment) provides a series of known and stable standard temperature points. The thermistor to be calibrated and a higher-precision standard thermometer (such as a second-class standard platinum resistance thermometer) are simultaneously placed in the constant temperature bath. After the temperature stabilizes, the resistance value of the thermistor corresponding to each standard temperature point is accurately recorded, thus obtaining a set of one-to-one corresponding raw data pairs. To improve the accuracy and practicality of the table, mathematical interpolation methods (such as spline interpolation in MATLAB) are usually used to expand the discrete measurement data points into a denser, more continuous data sequence. Then, according to the actual application's temperature range and accuracy requirements, the data is optimized and segmented. For example, denser data points are set in the temperature range where the thermistor resistance changes drastically to balance storage space and measurement accuracy. Ultimately, this processed and verified data will be compiled into an array or table and directly burned into the memory of the microprocessor 10. During actual measurement, the microprocessor 10 can look up the table using the measured real-time resistance value and quickly and accurately calculate the corresponding temperature value using algorithms such as table lookup or binary search.

[0067] Furthermore, step 4 specifically includes: Step 401: Microprocessor 10 reads the deviation value calculated in step 3 and runs the PID algorithm to calculate the required angle for rotating the curved mirror 1. Step 402: The microprocessor 10 converts the calculated angle into a pulse signal and sends it to the deflection mechanism; Step 403: The deflection mechanism executes the deflection command.

[0068] Furthermore, in step 5, the deflection mechanism includes a deflector that executes the deflection command, wherein the deflector is a stepper motor or a voice coil motor. Step 5 involves the following steps: The deflector drives the curved mirror 1 to deflect by a set angle according to the received pulse signal, so that the light focus moves away from the sensitive area of ​​the TFT.

[0069] Furthermore, in step 401, the PID algorithm calculates the set angle based on the deviation value and the required deflection angle formula. The formula for the deviation value and the required deflection angle is: α = 0.15 × Q, Q = (T - T1); Where α is the required deflection angle, Q is the deviation value, T is the current temperature value of the thermistor unit 5, and T1 is the secondary action threshold.

[0070] It is important to note that the 0.15 here refers to the coefficient k. Specifically, in the laboratory, when the curved mirror 1 is illuminated by strong light, a deflection of θ1 = 1.0° is sufficient to move the focus when the temperature T1 = 70°C. When the temperature T2 = 80°C, a deflection of θ2 = 2.5° is required. Based on the above data: k = (θ2 - θ1) / (T2 - T1) = (2.5 - 1.0) / (80 - 70) = 1.5 / 10 = 0.15 (°C / degree), the proportionality coefficient k is determined to be 0.15 to ensure that the deflection angle gains linearly with temperature deviation, avoiding overcorrection or under-response. In actual operation, the microprocessor 10 calculates the required deflection angle in real time according to this formula, driving the deflection mechanism to precisely control the attitude of the curved mirror 1.

[0071] Working principle: First, the microprocessor 10 sets multi-level temperature safety thresholds (e.g., Level 1 warning 60℃, Level 2 action 65℃, Level 3 limit 80℃). Then, multiple thermistor units 5, positioned at key locations in the HUD optical path, begin real-time temperature sensing. Each thermistor unit 5, together with a reference resistor 11, forms a voltage divider circuit. The resistance of this circuit changes with temperature, causing a change in the voltage at the divider point. The microprocessor 10 controls a multiplexer to sequentially connect each voltage divider circuit, acquiring voltage signals. The internal analog-to-digital converter then converts the analog voltage to a digital value and calculates the real-time resistance using the formula R1 = R2 × (V1 / V2 - 1). It then queries a pre-stored thermistor unit 5 resistance parameter table to calculate the accurate current temperature value. The microprocessor 10 then... The calculated temperature is then compared with the preset secondary action threshold. If the temperature exceeds the limit (e.g., reaching 70℃), the PID control algorithm is run based on the deviation value α=0.15×Q, Q=(T-T1) to calculate the required deflection angle of the curved mirror 1 (e.g., α=0.15×Q). This angle command is then converted into a pulse signal to drive the stepper motor, thereby causing the freeform mirror 1 to deflect at a small angle, causing the focused sunlight to move away from the sensitive area of ​​the TFT display screen. After that, the system immediately rescans the temperature sensor to verify the control effect and continuously cycles through the dynamic closed-loop process of "monitoring-judgment-execution-remonitoring" until the temperature of all areas returns to a safe level, thereby effectively dispersing heat accumulation and fundamentally suppressing the occurrence of screen burn-in.

[0072] Obviously, the embodiments described above are only some embodiments of this application, not all embodiments. The accompanying drawings show preferred embodiments of this application, but do not limit the patent scope of this application. This application can be implemented in many different forms; rather, the purpose of providing these embodiments is to provide a more thorough and comprehensive understanding of the disclosure of this application. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing specific embodiments, or make equivalent substitutions for some of the technical features. Any equivalent structures made using the content of this application's specification and drawings, directly or indirectly applied to other related technical fields, are similarly within the scope of patent protection of this application.

Claims

1. A device for solving screen burn-in by adjusting the focal position of a HUD curved mirror, characterized in that, The curved mirror (1) has a front side for display and a back side (2) set opposite to the front side. A sensing area (3) is provided on the back side (2) of the curved mirror (1) at the position corresponding to the focal point. The solution device includes a sensing module (4), a control system, and a deflection mechanism installed inside the vehicle. The deflection mechanism is configured to position a curved mirror (1), and the sensing module (4) is positioned and connected to the deflection mechanism. The sensing module (4) includes multiple thermistor units (5) for sensing temperature. All thermistor units (5) are arranged in the sensing area (3) to divide the sensing area (3) into multiple signal sensing parts (6). The control system is configured to control the deflection mechanism to deflect the curved mirror (1) by a set angle when one or more thermistor units (5) sense that the temperature of the corresponding signal sensing unit (6) exceeds a set temperature threshold.

2. The device for solving screen burn-in by adjusting the focal position of the HUD curved mirror according to claim 1, characterized in that, The sensing area (3) is arranged in a straight line; A dividing piece (7) is provided between adjacent signal sensing units (6) to separate each signal sensing unit (6). Alternatively, the back surface (2) may have recesses (8) at the corresponding positions of each signal sensing part (6) to separate each signal sensing part (6).

3. The device for solving screen burn-in by adjusting the focal position of the HUD curved mirror according to claim 2, characterized in that, Multiple thermistor units (5) are arranged in a linear array within the sensing area (3); Alternatively, the sensing area (3) can be divided into two equal parts along its length, with one part defined as the left side and the other as the right side. All the thermistor units (5) are arranged sequentially in the sensing area (3) in a left-right order.

4. The device for solving screen burn-in by adjusting the focal position of the HUD curved mirror according to claim 1, characterized in that, The control system includes a multiplexer (9), a microprocessor (10), and multiple reference resistors (11). The multiplexer (9) is electrically connected to the microprocessor (10); Each of the reference resistors (11) is connected in series with each thermistor unit (5) to form multiple voltage divider circuits, which are connected in parallel between the external power supply and the multiplexer (9). Each of the reference resistors (11) is also provided with a grounding point and a voltage divider point, which are located at the circuit nodes of the corresponding reference resistor (11) and the thermistor unit (5); Each voltage divider point on the reference resistor (11) is electrically connected to the multiplexer (9); the microprocessor (10) is configured to sequentially turn on multiple thermistor units (5) through the multiplexer (9), and at any given time only one voltage divider circuit is turned on to read data from the thermistor unit (5) in the voltage divider circuit.

5. A method for resolving screen burn-in by adjusting the focal position of the HUD curved mirror, characterized in that, The solution is achieved by the device described in any one of claims 1-4 that solves screen burn-in by adjusting the focal position of the HUD curved mirror; The solutions include: Step 1: Set the temperature safety threshold in the microprocessor (10); Step 2: The temperature of the corresponding signal sensing unit (6) is sensed in real time by multiple thermistor units (5) and transmitted to the microcontroller; Step 3: The microcontroller compares the actual temperature value fed back by the thermistor unit (5) with the preset temperature safety threshold and calculates the deviation value; Step 4: The microcontroller calculates and generates a control signal based on the deviation value using the PID algorithm, and then converts it into a control command to be output to the deflection mechanism. Step 5: The deflection mechanism guides the curved mirror (1) to reciprocate within a set angle; Step 6: Repeat steps 2 through 5.

6. The method for solving screen burn-in by adjusting the focal position of the HUD curved mirror according to claim 5, characterized in that, The temperature safety thresholds in step 1 include a level 1 warning threshold, a level 2 action threshold, and a level 3 extreme threshold; The first-level warning threshold is configured as the temperature range during the operation of the curved mirror (1); The secondary action threshold is configured as the temperature at which the deflection mechanism guides the curved mirror (1) to reciprocate within a set angle; The three-level limit threshold is configured as the automatic standby temperature of the curved mirror (1).

7. The method for solving screen burn-in by adjusting the focal position of the HUD curved mirror according to claim 5, characterized in that, Step 2 specifically includes: Step 201: The microprocessor (10) controls the multiplexer (9) through digital signals according to the preset order of the thermistor units (5) in the sensing area (3), so that only one voltage divider circuit is connected at a certain moment. Step 202: After the thermistor unit (5) senses the temperature change of the corresponding signal sensing unit (6), the resistance of the thermistor unit (5) changes in real time, which in turn causes the voltage at the voltage divider point in the connected voltage divider circuit to change, and transmits the voltage signal of the voltage divider circuit to the microprocessor (10). Step 203: The microprocessor (10) cyclically scans all voltage divider circuits to achieve "real-time" sensing.

8. The method for solving screen burn-in by adjusting the focal position of the HUD curved mirror according to claim 5, characterized in that, Step 3 specifically includes: Step 301: The microprocessor (10) converts the received voltage signal into a digital value through its internal analog-to-digital converter; Step 302: Calculate the current resistance value of the thermistor unit (5) according to the formula R1=R2×(V1 / V2-1), and then convert the current resistance value of the thermistor unit (5) into the current temperature value of the thermistor unit (5) by using the pre-stored thermistor unit (5) resistance parameter table. Where R1 is the current resistance value of the thermistor unit (5), R2 is the resistance value of the reference resistor (11), V1 is the resistance value of the working power supply voltage, and V2 is the digital value of the voltage signal of the voltage divider circuit. Step 303: Obtain the deviation value. Deviation value = current temperature value of the thermistor unit (5) - secondary action threshold.

9. The method for solving screen burn-in by adjusting the focal position of the HUD curved mirror according to claim 5, characterized in that, Step 4 specifically includes: Step 401: The microprocessor (10) reads the deviation value calculated in step 3 and runs the PID algorithm to calculate the angle to be rotated of the curved mirror (1); Step 402: The microprocessor (10) converts the calculated angle into a pulse signal and sends it to the deflection mechanism; Step 403: The deflection mechanism executes the deflection command; In step 401, the PID algorithm calculates the set angle based on the deviation value and the formula for the required deflection angle. The formula for the deviation value and the required deflection angle is: α = 0.15 × Q, Q = (T - T1); Where α is the required deflection angle, Q is the deviation value, T is the current temperature value of the thermistor unit (5), and T1 is the secondary action threshold.

10. The method for solving screen burn-in by adjusting the focal position of the HUD curved mirror according to claim 5, characterized in that, The deflection mechanism in step 5 includes a deflector that executes the deflection command, wherein the deflector is a stepper motor or a voice coil motor; Step 5 involves the following steps: The deflector drives the curved mirror (1) to deflect by a set angle according to the received pulse signal, so that the light focus moves away from the sensitive area of ​​the TFT.

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