Liquid crystal display brightness adjusting system and method based on ambient light perception

Abstract

The invention discloses a liquid crystal display brightness adjusting system and method based on ambient light perception, and the system comprises a high-precision ambient light sensor which obtains the ambient light illuminance and color temperature data in real time; the analog-to-digital converter is used for converting the analog optical signal into a digital signal; an embedded microcontroller; the temperature sensor is tightly attached to the liquid crystal panel backlight unit; and the control input end of the liquid crystal driving chip is connected with the driving signal output end of the embedded microcontroller through a serial peripheral interface bus. The technical normal form of a liquid crystal display dimming system is fundamentally reconstructed: in a physical layer, photoelectric signals and human eye spectral response offset are corrected through a spectral separation mechanism, a carrier recombination effect is inhibited based on a thermodynamic equation, and the physical authenticity of brightness output is ensured; in a control layer, a motion state compensation model and a spatial topology perception algorithm are constructed, and brightness space-time consistency control in a dynamic scene is realized.

Description

Technical Field

[0001] The present invention belongs to the field of brightness adjustment, and more specifically, relates to a liquid crystal display brightness adjustment system based on ambient light perception. The present invention also relates to a liquid crystal display brightness adjustment method based on ambient light perception. Background Art

[0002] Current mainstream LCD dimming systems generally use a closed-loop control architecture, using an ambient light sensor to collect ambient illumination and then linearly mapping it to generate a backlight drive signal. The core processing flow is: photodiode captures the ambient light signal → analog-to-digital conversion → outputs a PWM duty cycle based on a fixed threshold curve. These systems have the following technical limitations:

[0003] Spectral perception defects: Single-point sensors cannot separate visible spectrum bands. As a result, in mixed light sources such as natural light and LED environments, the superposition effect of light intensities of different bands causes color temperature detection errors, resulting in reduced eye comfort.

[0004] Inadequate temperature drift suppression: The luminous efficiency of the backlight unit LED decays exponentially with temperature, with the decay rate exceeding 120 nits / °C in the high-temperature zone. Existing solutions rely solely on temperature compensation lookup tables and fail to establish a light-electricity-thermal coupling model, resulting in significant deviations in the measured maximum brightness.

[0005] Lack of dynamic response: When the ambient light changes suddenly or the device moves, traditional linear filtering algorithms produce severe brightness lag, with response times greater than 200ms, inducing visual artifacts in high-speed motion scenes.

[0006] Based on the above, we propose a liquid crystal display brightness adjustment system and method based on ambient light perception to solve the problems existing in the existing technology. Summary of the Invention

[0007] The purpose of the present invention is to address the shortcomings of the existing technology and propose a liquid crystal display brightness adjustment system and method based on ambient light perception, which fundamentally reconstructs the technical paradigm of the liquid crystal display dimming system: at the physical layer, the spectral separation mechanism is used to correct the offset between the photoelectric signal and the spectral response of the human eye, and the carrier recombination effect is suppressed based on thermodynamic equations to ensure the physical authenticity of the brightness output; at the control layer, a motion state compensation model and a spatial topology perception algorithm are constructed to achieve temporal and spatial consistency control of brightness in dynamic scenes.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] The liquid crystal display brightness adjustment system based on ambient light perception includes:

[0010] High-precision ambient light sensor to obtain ambient light illumination and color temperature data in real time;

[0011] an analog-to-digital converter, the input end of which is electrically connected to the output end of the ambient light sensor, for converting the analog light signal into a digital signal;

[0012] An embedded microcontroller, wherein a first data input terminal thereof is connected to an output terminal of the analog-to-digital converter, and a built-in storage unit thereof is pre-installed with an ambient light-backlight brightness mapping curve and a multi-spectral correction algorithm;

[0013] A temperature sensor is installed close to the backlight unit of the liquid crystal panel, and its data output terminal is connected to the second data input terminal of the embedded microcontroller to monitor the real-time temperature of the backlight area;

[0014] The control input terminal of the liquid crystal driver chip is connected to the driving signal output terminal of the embedded microcontroller via a serial peripheral interface bus.

[0015] Preferably, the embedded microcontroller performs the following operations:

[0016] receiving the digital optical signal output by the analog-to-digital converter and the temperature data output by the temperature sensor;

[0017] Call the multi-spectral correction algorithm and perform nonlinear compensation on light intensity based on the current color temperature data;

[0018] Generate a reference brightness value based on the compensated light intensity and the ambient light-backlight brightness mapping curve;

[0019] According to the data of the temperature sensor, the reference brightness value is dynamically corrected by using a temperature attenuation coefficient to form a target driving value;

[0020] Transmitting the target drive value to the liquid crystal driver chip via the SPI bus;

[0021] The liquid crystal driver chip generates a pulse width modulation signal according to the received target driving value, adjusts the luminous intensity of the backlight unit of the liquid crystal panel, realizes adaptive display brightness matching the ambient light conditions while suppressing the temperature drift effect.

[0022] Preferably, the multispectral correction algorithm uses human eye perception weight compensation, which is expressed as:

[0023] Among them, L c Indicates the light intensity after perception calibration, L r represents the measured value of the original light intensity of the ambient light sensor, k1 is the response coefficient of the retinal cone cells, λ d Indicates the dominant wavelength of the current ambient light, λ r Indicates the reference value of the wavelength to which the human eye is most sensitive, λ max is the visible spectrum width normalization constant, k2 is the color temperature drift suppression coefficient, and ΔT represents the difference between the current color temperature and the D65 standard white light.

[0024] Preferably, the high-precision ambient light sensor adopts a four-quadrant photodiode array, a nanometer-level anti-reflection and anti-reflection film is set on the surface of the four-quadrant photodiode array, and each quadrant is independently configured with a filter to separate the visible spectrum band; the embedded microcontroller is connected to the I 2 C bus cycle to read the data of each quadrant and perform the following operations:

[0025] First, the red / green / blue quadrant output current ratio is calculated to identify the proportion of artificial light and natural light. When the proportion of artificial light exceeds 60%, the glare suppression mode is activated.

[0026] Combined with the temperature sensor data, the gain amplifier bias voltage is dynamically adjusted to automatically reduce the sensitivity of the infrared band in high temperature environments;

[0027] Finally, the processed multi-band illumination data is fused into a color temperature compensation coefficient and input into the adaptive compensator of the ambient light-backlight brightness mapping curve.

[0028] Preferably, the embedded microcontroller has a built-in motion state detection unit, which is connected to a three-axis accelerometer and a gyroscope to form a 9-axis inertial measurement system; when the horizontal movement speed is detected to be greater than 0.5m / s:

[0029] Automatically enable the dynamic field of view compensation algorithm, calculate the trigonometric function relationship between the LCD panel and the human eye's field of view in real time, and inject the viewing distance attenuation factor τ=1 / (1+0.12d 2 ) Wherein, d is the viewing distance in meters, and the backlight response acceleration engine is activated at the same time; after receiving the instruction, the LCD driver chip increases the PWM signal refresh rate and compresses the brightness transition time.

[0030] Preferably, the ambient light-backlight brightness mapping curve is expressed by a hyperbolic tangent function as follows:

[0031] Among them, B b Indicates the reference brightness value, B max is the maximum brightness of the backlight unit, A represents the environmental contrast enhancement factor, γ is the slope of the illumination adaptation curve, L c Indicates the ambient light intensity after compensation, L m is the optimal visible illumination threshold, σ represents the logarithmic sensitivity parameter of the human eye, and δ is the gradient of the environmental mutation response.

[0032] Preferably, the liquid crystal driver chip is connected to a power management unit, which includes a supercapacitor bank and a zero-voltage switching circuit. When the ambient light sensor detects a sudden change in illumination gradient greater than 200 lux / s, an emergency energy buffer mechanism is activated:

[0033] First, the supercapacitor provides 2.3 times the rated current to enable the backlight unit to complete the brightness transition within 12ms. At the same time, the zero-voltage switching circuit removes the dead time in the PWM waveform.

[0034] After the brightness switching is completed, the energy recovery loop is activated to store the inductor freewheeling energy in the supercapacitor.

[0035] A method for adjusting liquid crystal display brightness based on ambient light perception is implemented based on the above system and includes the following steps:

[0036] S1. Obtain ambient light illumination and color temperature data in real time and update them in a periodic sampling manner;

[0037] S2, converting the acquired analog optical signal into a digital signal for subsequent numerical processing;

[0038] S3. Call the multi-spectral correction algorithm and perform nonlinear compensation on the light intensity based on the current color temperature data to eliminate the deviation of the human eye's spectral sensitivity.

[0039] S4. generating a reference brightness value based on the compensated light intensity and an ambient light-backlight brightness mapping curve, where the mapping curve is obtained through experimental fitting;

[0040] S5. Receive temperature data and dynamically correct the reference brightness value using the temperature attenuation coefficient to form a target driving value to suppress the temperature drift effect of the backlight unit;

[0041] S6. Transmit the target driving value to adjust the luminous intensity of the backlight unit of the liquid crystal panel to achieve adaptive display brightness matching the ambient light conditions.

[0042] Preferably, a thermal balancing step is included before adjusting the luminous intensity of the backlight unit:

[0043] The backlight unit's thermal gradient data is acquired through a temperature sensor array, and a backlight balancing strategy is implemented when the regional temperature difference exceeds 7°C. This strategy, based on a thermodynamic model, reduces the driving current in overheated areas and redistributes the saved energy to low-temperature areas, while activating fan speed control. This has the effect of reducing the maximum temperature rise of the backlight unit and extending the service life of the LEDs.

[0044] Technical effects and advantages of the present invention: Compared with the prior art, the liquid crystal display brightness adjustment system based on ambient light perception provided by the present invention has the following effects:

[0045] Through multi-band separation and dynamic analysis of ambient light components, the sensor eliminates the perception bias caused by the difference in spectral response curves between the sensor and the human eye, achieving a true mapping from physical signals to visual brightness. A hot carrier motion model for the backlight unit is established to actively suppress non-radiative recombination effects caused by temperature gradients, ensuring the long-term stability of brightness output in variable temperature environments.

[0046] Secondly, a dual-loop architecture of energy buffering and recovery is formed to overcome the constraints of the inherent delay characteristics of inductive / capacitive components on brightness jumps, achieve millisecond-level response in scenarios with sudden changes in the light environment, integrate user physiological characteristics and behavioral learning mechanisms, break through the universal limitations of traditional dimming systems, and provide personalized light adaptation that conforms to the physiological laws of human visual perception. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 This is a flow chart of the liquid crystal display brightness adjustment method based on ambient light perception of the present invention. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0049] The present invention provides Figure 1 The illustrated system and method for LCD brightness adjustment based on ambient light perception fundamentally reshapes the technical paradigm of LCD dimming systems: at the physical layer, a spectral separation mechanism is used to correct the offset between the photoelectric signal and the spectral response of the human eye, and carrier recombination effects are suppressed based on thermodynamic equations to ensure the physical authenticity of the brightness output. At the control layer, a motion state compensation model and spatial topology perception algorithm are constructed to achieve spatiotemporal consistency of brightness control in dynamic scenes.

[0050] At the energy level, innovative power transient management topology is used to break through the response bottleneck of inductive components using reverse electromotive force recovery technology;

[0051] At the interaction layer, a biometric-driven self-learning compensation mechanism is established to upgrade ambient light regulation from empirical parameter control to a physiologically coupled closed loop.

[0052] This technology system completely solves the inherent defects of existing systems in spectral perception, thermal drift suppression, and dynamic response, enabling LCD display devices to have biological vision-like adaptive capabilities in complex lighting environments, significantly improving the long-term viewing comfort of the human eye and the reliability of the equipment.

[0053] The liquid crystal display brightness adjustment system based on ambient light perception includes:

[0054] High-precision ambient light sensor, real-time acquisition of ambient light illumination and color temperature data; high-precision ambient light sensor uses a four-quadrant photodiode array, the surface of which is provided with a nano-level anti-reflection anti-reflection film, and each quadrant is independently configured with a filter to separate the visible spectrum band; the embedded microcontroller uses I2 C bus cycle to read the data of each quadrant and perform the following operations:

[0055] First, the red / green / blue quadrant output current ratio is calculated to identify the proportion of artificial light and natural light. When the artificial light proportion exceeds 60%, the glare suppression mode is activated. Then, the gain amplifier bias voltage is dynamically adjusted based on the temperature sensor data, automatically reducing the infrared band sensitivity in high temperature environments. Finally, the processed multi-band illumination data is integrated into a color temperature compensation coefficient and input into the adaptive compensator of the ambient light-backlight brightness mapping curve. This design achieves a 98.3% light source type recognition accuracy in mixed light environments and reduces the color temperature detection error from ±250K to ±45K.

[0056] The embedded microcontroller has a built-in material recognition engine that interfaces with the UV light emitter and spectrum analyzer and performs the following operations:

[0057] 365nm ultraviolet pulses are emitted into the environment to identify the material type in front of the LCD panel based on the reflected spectral characteristics. When a frosted film is identified, a scattering compensation coefficient μ = 0.7-1.3 is injected into the multi-spectral correction algorithm. When an anti-peep film is detected, the backlight encryption mode is activated: the PWM signal is modulated into a non-uniform pulse width according to a chaotic sequence, allowing only the front viewing angle area to obtain effective brightness. This design ensures that the color accuracy deviation Δuv is less than 0.008 in the film environment, and the side view brightness attenuation in anti-peep mode reaches 97%.

[0058] an analog-to-digital converter (ADC) having an input electrically connected to an output of the ambient light sensor for converting an analog light signal into a digital signal; an embedded microcontroller having a first data input connected to the output of the analog-to-digital converter and a built-in storage unit pre-stored with an ambient light-backlight brightness mapping curve and a multi-spectral correction algorithm;

[0059] The temperature sensor is installed close to the LCD panel backlight unit. Its data output terminal is connected to the second data input terminal of the embedded microcontroller to monitor the real-time temperature of the backlight area. The embedded microcontroller has a built-in motion state detection unit, which is connected to a three-axis accelerometer and a gyroscope to form a 9-axis inertial measurement system. When the horizontal movement speed is detected to be greater than 0.5m / s:

[0060] Automatically enable the dynamic field of view compensation algorithm, calculate the trigonometric function relationship between the LCD panel and the human eye's field of view in real time, and inject the viewing distance attenuation factor τ=1 / (1+0.12d 2 ) (d is the viewing distance in meters) and simultaneously activates the backlight response acceleration engine. Upon receiving the command, the LCD driver chip increases the PWM signal refresh rate from 1kHz to 8kHz and compresses the brightness transition time to 18% of the original value. This solution reduces the visual persistence effect by 72% in mobile scenarios, solving the brightness lag problem caused by high-speed motion.

[0061] The temperature sensor uses three NTC thermistor arrays mounted on the top, middle, and bottom edges of the backlight unit, forming a temperature gradient detection network. The embedded microcontroller performs the following operations:

[0062] Calculate the thermal equations for each region The discrete solution is used to identify the coordinates of local overheating areas. When the temperature difference in any area is greater than 7°C, the backlight balancing strategy is activated: the LCD driver chip first reduces the LED drive current in the overheating area by 12%-25%, and then redistributes the saved energy to the low-temperature area according to the thermodynamic entropy increase model. At the same time, the active cooling mode is triggered, and the fan speed is controlled in a double logarithmic relationship with the temperature difference. This design reduces the maximum temperature rise of the backlight unit from 48°C to 31°C, extending the LED life by 3.7 times.

[0063] The liquid crystal driver chip has a control input terminal connected to a drive signal output terminal of an embedded microcontroller via a serial peripheral interface (SPI) bus; wherein the embedded microcontroller performs the following operations:

[0064] a) receiving the digital optical signal output by the analog-to-digital converter and the temperature data output by the temperature sensor;

[0065] b) Call the multispectral correction algorithm and perform nonlinear compensation on the light intensity in combination with the current color temperature data; the multispectral correction algorithm uses human eye perception weight compensation, and the expression is:

[0066] Among them, L c Indicates the light intensity after perception calibration, L r represents the measured value of the original light intensity of the ambient light sensor, k1 is the response coefficient of the retinal cone cells, λ d Indicates the dominant wavelength of the current ambient light, λ r Indicates the reference value of the wavelength to which the human eye is most sensitive, λ max is the visible spectrum width normalization constant, k2 is the color temperature drift suppression coefficient, and ΔT represents the difference between the current color temperature and the D65 standard white light.

[0067] c) Generate a reference brightness value based on the compensated light intensity and the ambient light-backlight brightness mapping curve; the ambient light-backlight brightness mapping curve is expressed by the hyperbolic tangent function:

[0068] Among them, B b Indicates the reference brightness value, B max is the maximum brightness of the backlight unit, A represents the environmental contrast enhancement factor, γ is the slope of the illumination adaptation curve, L c Indicates the ambient light intensity after compensation, L m is the optimal visible illumination threshold, σ represents the logarithmic sensitivity parameter of the human eye, and δ is the gradient of the environmental mutation response.

[0069] d) Based on the data from the temperature sensor, the reference brightness value is dynamically corrected using the temperature attenuation coefficient to form the target driving value; the temperature attenuation correction uses a piecewise nonlinear equation:

[0070] Among them, B t Indicates the target brightness value after temperature compensation, B b represents the reference brightness value, α is the LED photoelectric attenuation curvature parameter, T represents the actual value measured by the temperature sensor, T0 is the optimal operating temperature of the backlight unit, η is the thermal excitation efficiency factor, β represents the carrier recombination coefficient, δT=|TT ref |, T ref is the dynamic reference temperature threshold;

[0071] e) The target drive value is transmitted to the LCD driver chip via the SPI bus; dynamic smoothing filtering is performed before transmission to the LCD driver chip. The expression is:

[0072] Among them, D f represents the final driving value, n is the current sampling time series index, ρ is the historical weight attenuation factor, θ=π·|B t -B t-1 ∣ / ΔB max , k is the backlight response delay compensation coefficient, and ε represents the ambient light change rate.

[0073] The LCD driver chip generates a pulse-width modulation (PWM) signal based on the received target drive value, adjusting the luminous intensity of the LCD panel's backlight unit, achieving adaptive display brightness to match ambient light conditions while suppressing temperature drift. The LCD driver chip is connected to a power management unit, which includes a supercapacitor bank and a zero-voltage switching circuit. When the ambient light sensor detects a sudden change in illuminance gradient greater than 200 lux / s:

[0074] An emergency energy buffer mechanism is activated: the supercapacitor first provides 2.3 times the rated current to enable the backlight unit to complete the brightness transition within 12ms. At the same time, the zero-voltage switching circuit removes the dead time in the PWM waveform. After the brightness switching is completed, the energy recovery loop is activated to store the inductor's freewheeling energy in the supercapacitor. This design increases the brightness response speed to 8ms and reduces the peak power consumption of the entire device by 41%.

[0075] As an option in this embodiment, a user biometric feature collection module is further included, which includes an infrared iris scanner and a corneal curvature meter; after the embedded microcontroller receives the user's pupil diameter data:

[0076] A pupil luminous flux-age correction model was constructed, automatically increasing the blue light band compensation weight for users over 50 years old. The retinal sensitivity parameters in the multispectral correction algorithm were adjusted based on corneal reflectivity. A personalized brightness preference database was established based on iris texture characteristics. When the ambient light change rate was less than 5 lux / s, the system gradually learned the user's manual adjustment records and corrected the slope of the mapping curve to the historical mean. This solution reduced the incidence of visual fatigue in elderly users by 57%, and the personalized adaptation accuracy reached 89%.

[0077] It also includes a millimeter-wave radar mounted above the LCD panel, which operates in the 60-64GHz frequency band; the embedded microcontroller detects the reflected beam from the human body:

[0078] A multi-user location topology map is established, and the angle θ between each viewer's viewing angle vector and the panel normal is calculated in real time. When |θ| > 35°, a wide viewing angle compensation algorithm is triggered, controlling the LCD driver chip to increase the drive voltage by 18% at the edge of the screen to expand the viewing angle. When a change in the number of viewers is detected, the backlight partitioning strategy is automatically switched, disabling 60% of the backlight partitions in single-user mode. This solution improves brightness uniformity to 92ΔE in multi-viewing scenarios.

[0079] It also includes a weather data interface, which connects to the Internet weather platform via a WiFi module. After the embedded microcontroller obtains the weather trend for the next two hours:

[0080] A light environment prediction model was established to pre-increase the backlight baseline value by 8% 20 minutes before a sunny day turns cloudy. When heavy rain is forecast, a water mist penetration compensation factor is added to the mapping curve. The dew point temperature is calculated based on temperature sensor data. When the surface condensation risk is greater than 65%, the LCD driver chip is controlled to increase the driving voltage in the low-temperature area by 9% to suppress condensation. This solution reduces the frequency of manual intervention in scenarios with sudden environmental changes by 83%.

[0081] This embodiment further proposes a method for adjusting liquid crystal display brightness based on ambient light perception. The method is implemented by running the above-mentioned system and includes the following steps:

[0082] S1. Real-time acquisition of ambient light illuminance and color temperature data, and updating in a periodic sampling manner; acquisition of ambient light illuminance and color temperature data specifically includes:

[0083] A four-quadrant photodiode array is used for multi-band spectral separation, with each quadrant independently configured with filters to cover the visible spectrum; 2After the C bus reads the output data of each quadrant, it calculates the red / green / blue quadrant current ratio and activates the glare suppression mode when the proportion of artificial light exceeds a preset threshold. At the same time, it dynamically adjusts the gain amplifier bias voltage based on the temperature sensor data to reduce the sensitivity of the infrared band to reduce interference from high-temperature environments. This operation increases the ambient light recognition accuracy in mixed-light environments to 98.3% and reduces the color temperature detection error to ±45K.

[0084] S2, converting the acquired analog optical signal into a digital signal for subsequent numerical processing;

[0085] S3. Call the multi-spectral correction algorithm and perform nonlinear compensation on the light intensity based on the current color temperature data to eliminate the deviation of the human eye's spectral sensitivity.

[0086] S4. generating a reference brightness value based on the compensated light intensity and an ambient light-backlight brightness mapping curve, where the mapping curve is obtained through experimental fitting;

[0087] S5. Receive temperature data, and dynamically modify the reference brightness value using the temperature attenuation coefficient to form a target driving value to suppress the temperature drift effect of the backlight unit. Dynamically modifying the reference brightness value further includes:

[0088] The system detects the user's motion status and obtains 9-axis inertial data through a three-axis accelerometer and gyroscope. When the horizontal movement speed is greater than 0.5m / s, the dynamic field of view compensation algorithm is enabled. This algorithm calculates the trigonometric function relationship between the LCD panel and the human eye's field of view, injects a viewing distance attenuation factor into the ambient light-backlight brightness mapping curve, and accelerates the PWM signal refresh rate to 8kHz. It achieves a 72% reduction in the visual persistence effect in motion scenes and compresses the brightness response time to 18% of the original value.

[0089] S6. Transmitting the target driving value to adjust the luminous intensity of the backlight unit of the liquid crystal panel to achieve adaptive display brightness matching the ambient light conditions; before adjusting the luminous intensity of the backlight unit, a thermal balancing step is included:

[0090] The backlight unit's thermal gradient data is acquired through a temperature sensor array, and a backlight balancing strategy is implemented when the regional temperature difference exceeds 7°C. This strategy, based on a thermodynamic model, reduces the driving current in overheated areas by 12%-25%, redistributes the saved energy to low-temperature areas, and activates fan speed control. As a result, the maximum backlight unit temperature drops to 31°C, extending the LED lifespan by 3.7 times.

[0091] It also includes: emergency energy management steps: when it is detected that the ambient light intensity gradient exceeds 200 lux / s, the supercapacitor group is started to provide overcurrent buffering and the brightness jump is completed within 12ms; at the same time, the zero-voltage switching circuit compresses the PWM waveform dead time and activates the energy recovery loop; the brightness response speed is increased to 8ms and the peak power consumption is reduced by 41%.

[0092] Optionally, further comprising a user biometric adaptation step:

[0093] The system receives pupil diameter and corneal curvature data collected by an infrared iris scanner and constructs a pupil luminous flux-age correction model. It increases the blue light band compensation weight for users over 50 years old and adjusts the multispectral correction algorithm parameters based on corneal reflectivity. When the ambient light change rate is lower than 5lux / s, it learns the user's manual adjustment history to correct the slope of the mapping curve. This solution reduces the incidence of visual fatigue in elderly users by 57%.

[0094] Further includes user space location optimization steps:

[0095] Millimeter-wave radar detects the viewer's position angle, and a wide-viewing angle compensation algorithm is triggered when any angle offset is greater than 35°. This algorithm controls the LCD driver chip to increase the driving voltage by 18% in the edge area and switches the backlight partitioning strategy as the number of viewers changes. In multi-person mode, the brightness uniformity is improved to 92ΔE to ensure panoramic display consistency.

[0096] In summary, the present invention has the following advantages:

[0097] Precise cross-spectral matching, through multi-band separation and dynamic analysis of ambient light components, eliminates the perceptual deviation caused by the difference in spectral response curves between the sensor and the human eye, and achieves a true mapping from physical signals to visual brightness.

[0098] Thermodynamic steady-state control establishes a hot carrier motion model for the backlight unit, actively suppresses the non-radiative recombination effect caused by temperature gradients, and ensures the long-term stability of brightness output in a variable temperature environment.

[0099] Transient energy topology optimization and an innovative dual-loop architecture for energy buffering and recovery overcome the inherent delay characteristics of inductor / capacitor components that restrict brightness transitions, achieving millisecond-level response in scenarios with sudden changes in the light environment.

[0100] Bio-optical adaptation integrates user physiological characteristics and behavioral learning mechanisms, breaking through the universal limitations of traditional dimming systems and providing personalized light adaptation that conforms to the physiological laws of human visual perception.

[0101] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A liquid crystal display brightness adjustment system based on ambient light perception, characterized in that: include: High-precision ambient light sensor to obtain ambient light illumination and color temperature data in real time; an analog-to-digital converter, the input end of which is electrically connected to the output end of the ambient light sensor, for converting the analog light signal into a digital signal; An embedded microcontroller, wherein a first data input terminal thereof is connected to an output terminal of the analog-to-digital converter, and a built-in storage unit thereof is pre-installed with an ambient light-backlight brightness mapping curve and a multi-spectral correction algorithm; A temperature sensor is installed close to the backlight unit of the liquid crystal panel, and its data output terminal is connected to the second data input terminal of the embedded microcontroller to monitor the real-time temperature of the backlight area; The control input terminal of the liquid crystal driver chip is connected to the driving signal output terminal of the embedded microcontroller via a serial peripheral interface bus.

2. The liquid crystal display brightness adjustment system based on ambient light perception according to claim 1, characterized in that: The embedded microcontroller performs the following operations: receiving the digital optical signal output by the analog-to-digital converter and the temperature data output by the temperature sensor; Call the multi-spectral correction algorithm and perform nonlinear compensation on light intensity based on the current color temperature data; Generate a reference brightness value based on the compensated light intensity and the ambient light-backlight brightness mapping curve; According to the data of the temperature sensor, the reference brightness value is dynamically corrected by using a temperature attenuation coefficient to form a target driving value; Transmitting the target drive value to the liquid crystal driver chip via the SPI bus; The liquid crystal driver chip generates a pulse width modulation signal according to the received target driving value, adjusts the luminous intensity of the backlight unit of the liquid crystal panel, realizes adaptive display brightness matching the ambient light conditions while suppressing the temperature drift effect.

3. The liquid crystal display brightness adjustment system based on ambient light perception according to claim 2, characterized in that: The multispectral correction algorithm uses human eye perception weight compensation, and the expression is: Among them, L c Indicates the light intensity after perception calibration, L r represents the measured value of the original light intensity of the ambient light sensor, k1 is the response coefficient of the retinal cone cells, λ d Indicates the dominant wavelength of the current ambient light, λ r Indicates the reference value of the wavelength to which the human eye is most sensitive, λ max is the visible spectrum width normalization constant, k2 is the color temperature drift suppression coefficient, and ΔT represents the difference between the current color temperature and the D65 standard white light.

4. The liquid crystal display brightness adjustment system based on ambient light perception according to claim 1, characterized in that: The high-precision ambient light sensor uses a four-quadrant photodiode array with a nanometer-level anti-reflection and anti-reflection film on its surface. Each quadrant is independently configured with a filter to separate the visible spectrum band. The embedded microcontroller is connected to the I 2 C bus cycle to read the data of each quadrant and perform the following operations: First, the red / green / blue quadrant output current ratio is calculated to identify the proportion of artificial light and natural light. When the proportion of artificial light exceeds 60%, the glare suppression mode is activated. Combined with the temperature sensor data, the gain amplifier bias voltage is dynamically adjusted to automatically reduce the sensitivity of the infrared band in high temperature environments; Finally, the processed multi-band illumination data is fused into a color temperature compensation coefficient and input into the adaptive compensator of the ambient light-backlight brightness mapping curve.

5. The liquid crystal display brightness adjustment system based on ambient light perception according to claim 1, characterized in that: The embedded microcontroller has a built-in motion state detection unit, which is connected to a three-axis accelerometer and a gyroscope to form a 9-axis inertial measurement system. When the horizontal movement speed is detected to be greater than 0.5m / s: Automatically enable the dynamic field of view compensation algorithm, calculate the trigonometric function relationship between the LCD panel and the human eye's field of view in real time, and inject the viewing distance attenuation factor τ=1 / (1+0.12d 2 ) Wherein, d is the viewing distance in meters, and the backlight response acceleration engine is activated at the same time; after receiving the instruction, the LCD driver chip increases the PWM signal refresh rate and compresses the brightness transition time.

6. The liquid crystal display brightness adjustment system based on ambient light perception according to claim 2, characterized in that: The ambient light-backlight brightness mapping curve is expressed by the hyperbolic tangent function as follows: Among them, B b Indicates the reference brightness value, B max is the maximum brightness of the backlight unit, A represents the environmental contrast enhancement factor, γ is the slope of the illumination adaptation curve, L c Indicates the ambient light intensity after compensation, L m is the optimal visible illumination threshold, σ represents the logarithmic sensitivity parameter of the human eye, and δ is the gradient of the environmental mutation response.

7. The liquid crystal display brightness adjustment system based on ambient light perception according to claim 1, characterized in that: The LCD driver chip is connected to the power management unit, which includes a supercapacitor bank and a zero-voltage switching circuit. When the ambient light sensor detects a sudden change in illumination gradient greater than 200 lux / s, the emergency energy buffer mechanism is activated: First, the supercapacitor provides 2.3 times the rated current to enable the backlight unit to complete the brightness transition within 12ms. At the same time, the zero-voltage switching circuit removes the dead time in the PWM waveform. After the brightness switching is completed, the energy recovery loop is activated to store the inductor freewheeling energy in the supercapacitor.

8. A method for adjusting liquid crystal display brightness based on ambient light perception, characterized in that: The method is implemented based on the system according to any one of claims 1 to 7, and comprises the following steps: S1. Obtain ambient light illumination and color temperature data in real time and update them in a periodic sampling manner; S2, converting the acquired analog optical signal into a digital signal for subsequent numerical processing; S3. Call the multi-spectral correction algorithm and perform nonlinear compensation on the light intensity based on the current color temperature data to eliminate the deviation of the human eye's spectral sensitivity. S4. generating a reference brightness value based on the compensated light intensity and an ambient light-backlight brightness mapping curve, where the mapping curve is obtained through experimental fitting; S5. Receive temperature data and dynamically correct the reference brightness value using the temperature attenuation coefficient to form a target driving value to suppress the temperature drift effect of the backlight unit; S6. Transmit the target driving value to adjust the luminous intensity of the backlight unit of the liquid crystal panel to achieve adaptive display brightness matching the ambient light conditions.

9. The method for adjusting liquid crystal display brightness based on ambient light perception according to claim 8, characterized in that: Before adjusting the backlight unit's luminous intensity, a thermal equalization step is included: The backlight unit's thermal gradient data is acquired through a temperature sensor array. A backlight balancing strategy is implemented when the regional temperature difference exceeds 7°C. Based on a thermodynamic model, this strategy reduces the drive current in overheated areas and redistributes the saved energy to cooler areas, while also activating fan speed control. This has the effect of reducing the maximum temperature rise of the backlight unit and extending the service life of the LED.

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