A TFT-LCD dynamic partition backlight energy saving method and system

Abstract

The application discloses a TFT-LCD dynamic partition backlight energy-saving method and system, relates to the technical field of liquid crystal display, extracts brightness characteristics through pre-processing of an input image signal, realizes adaptive dynamic partition of a display panel based on a brightness gradient clustering algorithm, calculates optimal backlight threshold values of the partitions in combination with backlight module defect compensation rules, independently regulates and controls backlight driving currents of the partitions, synchronously cooperates with liquid crystal transmittance compensation, and realizes whole-process steady-state regulation and control through closed-loop feedback optimization. The system comprises a main control module, an image processing module, an adaptive partition module, a brightness threshold value calculation module, a backlight driving module, a TFT driving module, a feedback detection module and a matching backlight module. The application greatly reduces invalid backlight power consumption, improves display contrast, adapts to various large and small size TFT-LCD display devices, has strong structure adaptability and stable control, and has excellent energy-saving effect and display quality.

Description

Technical Field

[0001] This invention relates to the field of liquid crystal display technology, and in particular to a method and system for energy saving of dynamic partitioned backlight in TFT-LCD. Background Technology

[0002] Thin Film Transistor Liquid Crystal Display (TFT-LCD) is an active matrix liquid crystal display technology that uses liquid crystal as the display medium and thin film transistors as the pixel driving units. With its small size, low power consumption, and no radiation, TFT-LCD dominates the flat panel display market and is widely used in televisions, monitors, mobile terminals and other devices.

[0003] In existing TFT-LCD backlight control technologies, global dimming achieves energy saving by adjusting the overall backlight brightness, but it cannot precisely control the brightness according to the local differences in the displayed image, resulting in wasted backlight in bright areas and insufficient contrast in dark areas. Traditional local dimming technology uses a fixed local dimming mode with fixed local dimming granularity, which cannot adapt to dynamic changes in the image. This results in uneven brightness at local dimming boundaries and limited energy-saving effects. At the same time, it does not consider the impact of the inherent physical defects of the backlight module on display consistency and energy-saving effects. Summary of the Invention

[0004] This application provides a TFT-LCD dynamic partitioned backlight energy-saving method and system. Addressing the problems of poor energy-saving effect, insufficient display contrast, poor partition adaptability, and lack of hardware defect compensation in existing TFT-LCD backlight energy-saving technologies, this invention provides a TFT-LCD dynamic partitioned backlight energy-saving method and system. Through adaptive dynamic partitioning, precise backlight brightness control, and coordinated compensation of liquid crystal transmittance, combined with backlight module hardware structure optimization, it maximizes the reduction of backlight power consumption while ensuring display quality.

[0005] This application provides a method for energy-saving dynamic partitioning backlight of a TFT-LCD. Includes the following steps: S1 Image Acquisition and Preprocessing: The input image signal is acquired through the image receiving module of the TFT-LCD, and the image signal is subjected to noise reduction and grayscale processing. The pixel brightness features of the image are extracted. At the same time, the inherent physical property features and defect features of the TFT-LCD backlight module are acquired, and a defect compensation mapping rule library is established. S2 Adaptive Dynamic Partitioning: Based on the preprocessed image pixel brightness characteristics, a brightness gradient clustering algorithm is used to divide the TFT-LCD display panel into several dynamic backlight partitions. The number, size and shape of the dynamic backlight partitions are adaptively adjusted in real time according to the brightness distribution of the input image. Each dynamic backlight partition corresponds to an independent backlight driving unit, and the partition boundary is adapted to the light-emitting area of ​​the TFT-LCD light guide plate. S3 partition brightness threshold calculation: For each dynamic backlight partition, the average brightness, peak brightness and variance of all pixels in the partition are statistically analyzed. Combined with the defect compensation mapping rule library, the optimal backlight brightness threshold of the partition is calculated. The optimal backlight brightness threshold meets the minimum power consumption requirement under the premise that the display effect of the partition meets the standard. S4 Backlight Driver Adjustment: Based on the optimal backlight brightness threshold of each dynamic backlight zone, the operating current of the corresponding backlight driver unit is independently adjusted through the backlight driver module to achieve differentiated brightness output for different dynamic backlight zones. For zones with an average brightness value lower than the preset dark state threshold, the corresponding backlight driver unit is controlled to reduce the current until it is turned off. S5 LCD Transmittance Collaborative Compensation: Synchronously acquire the transmittance parameters of the LCD panel pixels corresponding to each dynamic backlight zone, and finely adjust the transmittance of the corresponding area LCD pixels through the TFT driving module according to the backlight brightness threshold of the zone to compensate for the uneven brightness at the zone boundary. S6 Dynamic Feedback Optimization: Real-time acquisition of actual backlight brightness, liquid crystal transmittance and power consumption data of each dynamic backlight zone, comparison with preset standard parameters, and dynamic correction of brightness threshold and drive current of each zone through feedback adjustment algorithm to form closed-loop control.

[0006] Furthermore, the system includes: The image processing module is connected to the image receiver of the TFT-LCD. It is used to receive input image signals and perform preprocessing, extract pixel brightness features, collect physical properties and defect features of the backlight module, and establish and maintain a defect compensation mapping rule base. The adaptive partitioning module is connected to the image processing module and has a built-in brightness gradient clustering algorithm. It is used to divide the dynamic backlight partitions in real time according to the brightness characteristics of image pixels, and determine the number, size, shape and corresponding backlight driving unit of each partition. The brightness threshold calculation module, connected to the adaptive partitioning module, is used to statistically analyze the pixel brightness parameters of each dynamic backlight partition and, in conjunction with the defect compensation mapping rule base, calculate the optimal backlight brightness threshold for each partition. The backlight module includes a light guide plate, a light strip, and several independent backlight driving units. The light-emitting surface of the light guide plate is divided into light-emitting areas adapted to the dynamic backlight partitions. The light-emitting direction of the light strip is towards the light-incident surface of the light guide plate. The backlight driving units correspond one-to-one with the dynamic backlight partitions. The backlight driving module is connected to the brightness threshold calculation module and the backlight module respectively, and is used to independently control the operating current of each backlight driving unit according to the optimal backlight brightness threshold. The TFT driving module, connected to the backlight driving module and the TFT-LCD liquid crystal panel, is used to fine-tune the transmittance of the liquid crystal pixels in the corresponding area according to the backlight brightness threshold of each dynamic backlight zone. The feedback detection module is connected to the backlight module and the TFT driving module respectively, and is used to collect and feed back the actual backlight brightness, liquid crystal transmittance and power consumption data of each dynamic backlight zone in real time. The main control module is connected to all the above modules and is used to coordinate the working sequence of each module, execute closed-loop feedback optimization logic, and control the operation of the entire system.

[0007] Furthermore, the light guide plate of the backlight module is made of PMMA material, with a reflective layer on the bottom surface. The light strip is a side-lit LED light strip, and each backlight driving unit corresponds to a set of LED beads. It adopts PWM dimming mode with a PWM dimming frequency of 100Hz-200Hz.

[0008] Furthermore, the image processing module uses an FPGA chip, which has a built-in Gaussian filtering module and a grayscale processing module. The adaptive partitioning module and the brightness threshold calculation module are integrated into the ARM processor. The FPGA chip communicates with the ARM processor through an SPI interface, and the communication rate is no less than 1Mbps.

[0009] Furthermore, the brightness gradient clustering algorithm in S2 is the K-means algorithm, with a cluster size range of 16-256. The number of dynamic backlight partitions is automatically determined based on the changes in image brightness gradient, and the number of clustering iterations does not exceed 50.

[0010] Furthermore, the defect compensation mapping rule library in S1 includes three defect types: LED chip attenuation, light guide plate scratches, and non-uniform refractive index of the backlight module. Each defect type corresponds to a different brightness compensation parameter, with the compensation parameter range being 0-10, which is dynamically adjusted according to the severity of the defect.

[0011] Furthermore, the feedback adjustment algorithm in S6 adopts a PID adjustment algorithm with a proportional coefficient of 0.5-1.5, an integral coefficient of 0.1-0.3, and a derivative coefficient of 0.05-0.15, to ensure the stability and fast response of the brightness threshold and drive current correction.

[0012] Furthermore, the brightness sensor in the feedback detection module is a digital brightness sensor with a detection accuracy of 0.1 lux and a sampling frequency of 10Hz-20Hz. The power consumption detection chip has a detection accuracy of no less than 1%, ensuring the accuracy of the collected data. The main control module also includes a storage unit for storing preset standard parameters, defect compensation mapping rule base and historical operation data. The storage capacity is not less than 16GB and supports data retention after power failure.

[0013] One or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages: Adaptive dynamic zoning is adopted, and the number and size of zoning are adjusted in real time according to the image brightness distribution. Combined with differentiated backlight driving for zoning, the backlight can be turned off in dark areas, which greatly reduces the ineffective power consumption of the backlight module. By coordinating the transmittance of the liquid crystal, the problem of uneven brightness at the boundary of dynamic partitions is solved. At the same time, combined with the backlight module defect compensation mechanism, the consistency and contrast of the display are improved, the details in the dark area are clearer, the colors in the bright area are more vivid, and the energy saving and display effect are balanced. Breaking through the limitations of traditional fixed partitioning, it achieves adaptive partitioning adjustment, while integrating backlight defect compensation and liquid crystal transmittance coordinated control. Detailed Implementation

[0014] This invention can be implemented in many different forms and is not limited to the embodiments described herein; rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this invention.

[0015] It should be noted that the terms "vertical," "horizontal," "up," "down," "left," "right," and similar expressions used in this article are for illustrative purposes only and do not represent the only possible implementation.

[0016] 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 invention pertains; the terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to limit the invention; the term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0017] Example 1: A method for energy saving in dynamic local dimming backlighting of TFT-LCD is provided in this embodiment. This method is applied to a 55-inch 4K ultra-high-definition TFT-LCD television with a resolution of 3840×2160 and a refresh rate of 60Hz. The television uses an edge-lit LED backlight module and an ADS Pro hard screen LCD panel. The specific steps are as follows: 1. Image Acquisition and Preprocessing: The input image signal is received via the HDMI 2.1 interface of the TV. The input signal format is 4K@60Hz with a color depth of 10bit. A Gaussian filtering algorithm is used to reduce noise in the image signal. The sigma value of the Gaussian filter is set to 1.2, and the convolution kernel size is 3×3, which can effectively remove high-frequency noise in the image and avoid noise interference with brightness feature extraction. Then, a weighted average grayscale algorithm is used to convert the color image into a grayscale image. The grayscale weights are set to R:0.299, G:0.587, and B:0.114, and the grayscale value of each pixel is extracted.

[0018] Simultaneously, the physical properties and defect characteristics of the backlight module are collected through temperature sensors and brightness sensors. The physical properties include the refractive index of the light guide plate, the luminous efficiency of the LED strip, and the rated current of the LED beads. The defect characteristics include the brightness decay of the LED beads, scratches on the light guide plate, and uneven refractive index of the light guide plate. A defect compensation mapping rule library is established to store the brightness compensation parameters corresponding to different defects.

[0019] For example: the compensation parameter for LED attenuation rate below 10% is 3, the compensation parameter for 10%-20% is 5, and the compensation parameter for 20%-30% is 8; the compensation parameter for scratch length of light guide plate below 3mm is 2, and the compensation parameter for 3mm to 5mm is 4; the compensation parameter for refractive index deviation below ±0.01 is 1, and the compensation parameter for ±0.01-±0.02 is 2. The rule base supports real-time updates through the main control module.

[0020] Preferably, the grayscale range of each pixel is 0-255, corresponding to a brightness of 0 lux-1000 lux. The collected grayscale values, physical attributes and defect features collected by the sensor are input into the main control module. Combined with the defect compensation mapping rule library, the corresponding compensation parameters are called to correct the target brightness of each partition. Finally, the dynamic brightness output value of the partition is obtained to adapt to the current screen display content and backlight hardware status. The main control module then sends a brightness adjustment command to the backlight driver board to control the LED beads of the corresponding partition to adjust the output power. Under the premise of ensuring that the contrast of the display screen meets the requirements, the output power of the backlight in non-high brightness areas is reduced to achieve energy saving effect.

[0021] Preferably, the temperature sensor is a DS18B20, installed on the edge of the backlight panel, used to collect the operating temperature of the backlight module in real time and transmit it to the main control module to correct the compensation parameters: when the operating temperature is higher than the preset threshold, the light decay rate of the LEDs will accelerate, and the main control module will automatically increase the brightness compensation parameters of the corresponding zone to avoid premature brightness decay due to temperature rise and ensure that the output brightness of the zone meets the preset requirements; when the operating temperature is lower than the preset threshold, the compensation parameters will be appropriately reduced to avoid excessive LED output power and further optimize the energy saving effect.

[0022] Preferably, the brightness sensor model TSL2561 is installed at the top center of the monitor's outer frame to collect ambient light brightness in real time and transmit it to the main control module to adjust the overall backlight output benchmark: when the ambient light brightness is low, the main control module will lower the benchmark brightness of all zones to further reduce backlight power consumption while ensuring the comfort of human eyes; when the ambient light brightness is high, it will automatically raise the overall benchmark brightness to ensure that the screen display content is clearly visible and avoid the screen becoming washed out and unclear due to excessive ambient light.

[0023] 2. Adaptive Dynamic Partitioning: Based on the pixel brightness features of grayscale images, the K-means brightness gradient clustering algorithm is adopted, with the number of clusters set to a range of 16-256 and the maximum number of clustering iterations set to 50. The algorithm automatically determines the number of clusters, i.e. the number of dynamic backlight partitions, according to the changes in image brightness gradient. The clustering termination condition is that the deviation of the cluster centers between two adjacent iterations is less than 0.5.

[0024] The TV display panel is divided into several dynamic backlight zones, and the zone boundaries are precisely matched with the light-emitting area of ​​the light guide plate, with an matching error of no more than 0.1mm.

[0025] The specific adaptation scenarios are as follows: When displaying a completely black screen, the number of partitions is automatically adjusted to 16, and all partitions are in a dark state to reduce the power consumption of the drive unit; when displaying a screen with strong contrast between light and dark, such as stars in the night sky, the number of partitions is automatically adjusted to 128, with the bright areas corresponding to the stars divided into independent small partitions of 16×16 pixels, and the dark areas of the night sky divided into large partitions of 64×64 pixels. Each partition corresponds to an independent LED backlight drive unit to ensure clear details in the bright areas and no waste of backlight in the dark areas; when displaying regular video screens, the number of partitions is automatically adjusted to 64, balancing energy saving and display smoothness.

[0026] 3. Calculation of brightness threshold for each zone: For each dynamic backlight zone, the image processing module calculates the mean brightness, peak brightness, and variance of all pixels in the zone with a precision of 1 gray level. Combined with the defect compensation mapping rule library, the compensation parameters for the corresponding defects in the zone are queried.

[0027] The formula used is: X = (Y × 0.7 + Z × 0.3) + T; Where X is the optimal backlight brightness threshold, Y is the average brightness, Z is the peak brightness, and T is the compensation parameter.

[0028] Calculate the optimal backlight brightness threshold for the partition. The optimal backlight brightness threshold satisfies the minimum power consumption requirement under the premise that the display effect of the partition meets the standard, and the threshold range is limited to 0-255, corresponding to a backlight brightness of 0 lux-1000 lux.

[0029] For example, if a certain zone has an average brightness of 20, a peak brightness of 30, a variance of 5, and slight LED attenuation of 8%, with a compensation parameter of 3, then the optimal backlight brightness threshold for this zone is (20×0.7+30×0.3)+3=14+9+3=26, ensuring that the zone displays details in dark states while avoiding backlight waste. If a certain zone has an average brightness of 200, a peak brightness of 255, a variance of 10, no obvious defects, and a compensation parameter of 0, then the optimal backlight brightness threshold is (200×0.7+255×0.3)+0=140+76.5=216.5, which is rounded to 217, matching the requirements for bright state display.

[0030] 4. Backlight driver adjustment: The backlight module adopts side-lit LED light strips, with a total of 8 light strips. Each light strip contains 16 groups of LED beads, and each group of LED beads corresponds to a backlight driver unit, for a total of 128 independent backlight driver units. The backlight driver unit uses an LED driver chip and supports PWM dimming. The PWM dimming frequency is set to 150Hz to avoid flickering and affecting the visual experience.

[0031] 5. The backlight driver module uses a dedicated backlight driver chip. Based on the optimal backlight brightness threshold of each zone, it adjusts the PWM duty cycle of the corresponding backlight driver unit to control the operating current. The PWM duty cycle adjustment accuracy is 1%.

[0032] The preset dark threshold is set to 30, and the preset bright threshold is set to 100: For zones with an average brightness below 30, the PWM duty cycle of the corresponding backlight driver unit is controlled to 0, turning off the backlight. At this time, the power consumption of the driver unit drops to below 0.01W; for zones with an average brightness between 30 and 100, the PWM duty cycle is adjusted to 10% to 30%, corresponding to a working current of 5mA to 15mA; for zones with an average brightness above 100, the PWM duty cycle is adjusted to 30% to 100%, corresponding to a working current of 15mA to 20mA, to achieve differentiated brightness output and minimize ineffective power consumption.

[0033] Preferably, the LED driver chip is the PT4115. This chip supports wide voltage input, and the output current can be continuously adjusted via PWM signal, exhibiting high constant current accuracy. It also features built-in over-temperature protection, automatically reducing output power under high load conditions to ensure the long-term stability of the backlight driver unit. The driver chips are positioned on the extended side of the light strip, with each chip driving four groups of LEDs, matching the LED arrangement of the light strip and reducing signal loss during transmission.

[0034] Preferably, the backlight driver chip is the MAX16835. This chip supports up to 32 independent dimming channels and can simultaneously output independent PWM control signals to LEDs in different zones. It has higher integration and eliminates the need for additional multi-channel selection chips, reducing the overall number of components in the backlight driver unit and compressing the manufacturing cost and space occupied by the backlight module. Each driver chip drives all LEDs in a brightness zone, and the control signals do not need to be transmitted across zones, further reducing the possibility of signal interference and improving the accuracy of zone brightness control. At the same time, the chip also has built-in overheat and overcurrent protection mechanisms. When the chip's operating temperature exceeds the threshold or the output current is abnormal, it will automatically trigger protection to cut off the output of the corresponding channel to prevent the fault from spreading and damaging the backlight module.

[0035] 6. Liquid crystal transmittance collaborative compensation: The initial transmittance of the liquid crystal panel pixels corresponding to each dynamic backlight zone is obtained through the TFT driving module. The initial transmittance ranges from 5% to 90%. Based on the backlight brightness threshold of the zone, the transmittance of the corresponding liquid crystal pixels is finely adjusted in a linear adjustment manner, with a fine adjustment range of ±5% to ±15%.

[0036] The specific adjustment rules are as follows: when the backlight brightness threshold is ≤50, it is a dark zone, and the transmittance is increased by 5%-15%. The lower the threshold, the greater the increase. When the backlight brightness threshold is ≥150, it is a bright zone, and the transmittance is decreased by 5%-15%. The higher the threshold, the greater the decrease. When the backlight brightness threshold is between 50 and 150, it is a normal zone, and the transmittance is finely adjusted by ±5%.

[0037] For example, in the dark zone with a backlight brightness threshold of 26, the initial transmittance is 10%, which is increased by 12% to achieve a transmittance of 22%, ensuring clear details in the dark areas; in the bright zone with a backlight brightness threshold of 217, the initial transmittance is 85%, which is decreased by 10% to achieve a transmittance of 75%, preventing the image from being too bright and dazzling; at the same time, the difference in brightness transition between adjacent zones is compensated to ensure that the brightness transition difference between adjacent zones is ≤5 lux, ensuring a continuous and consistent image without obvious zone artifacts.

[0038] Preferably, the TFT driving module is model ILI9806. This driving module can support the maximum resolution output and can match the current 55-inch display's zonal driving requirements. It can simultaneously complete the output of backlight zonal brightness signals and liquid crystal pixel transmittance signals without the need for an additional independent backlight driving chip, thereby reducing the overall hardware cost of the system and realizing an integrated design where a single module completes dual driving tasks.

[0039] 7. Dynamic Feedback Optimization: The actual backlight brightness of each dynamic backlight zone is collected in real time, with a sampling frequency of 15Hz and a detection accuracy of 0.1 lux. The power consumption data of each backlight driver unit is collected through a power consumption detection chip, with a sampling frequency of 10Hz and a detection accuracy of 1%. The collected data is fed back to the brightness threshold calculation module through the I2C interface and compared with the preset standard parameters.

[0040] A PID control algorithm is used for dynamic correction. The PID parameters are set as follows: proportional coefficient 1.0, integral coefficient 0.2, and derivative coefficient 0.1 to ensure the stability and fast response of the correction.

[0041] The specific correction logic is as follows: if the actual brightness of a certain zone is less than 5% of the optimal threshold, the PWM duty cycle of the corresponding backlight driver unit is appropriately increased; if the actual brightness is more than 5% of the optimal threshold, the PWM duty cycle is decreased; if the actual power consumption is higher than the preset power consumption threshold, which is set according to the size of the zone and ranges from 0.05W to 0.2W, the optimal brightness threshold of that zone is appropriately decreased by 5 to 10 gray levels, forming a closed-loop control to continuously optimize energy saving effect and display quality, with a closed-loop adjustment response time ≤100ms.

[0042] Preferably, the power consumption detection chip, model INA219, is a mainstream digital current / power monitoring chip that supports I2C interface communication and can directly output the voltage, current, and real-time power consumption data of the backlight driver unit. Its operating voltage range is 2.7V to 26V, which is fully compatible with the common backlight driver power supply specifications of 27-inch local dimming displays. In addition, the built-in calibration register simplifies the data processing flow and ensures that the detection accuracy meets the design requirement of 1% without the need for additional complex parameter calibration. It can stably match the acquisition requirements of this solution.

[0043] Example 2: This embodiment provides a TFT-LCD dynamic local dimming backlight energy-saving system to implement the method of Embodiment 1, applied to a 55-inch 4K ultra-high-definition TFT-LCD TV, with the following specific structure: 1. Image Processing Module: Employs an FPGA chip with an operating voltage of 3.3V and a frequency of 50MHz. It connects to the TV's HDMI 2.1 interface to receive input image signals. It includes a built-in Gaussian filter module and a grayscale processing module. The Gaussian filter module uses hardware-accelerated logic, and the grayscale processing module supports rapid conversion to 10-bit color depth. It also connects to temperature and brightness sensors. The temperature sensors have a sampling frequency of 1Hz and a detection range of -40℃ to 85℃, used to collect the operating temperature of the backlight module. Sixteen brightness sensors are evenly distributed on the back of the LCD panel to collect defect features of the backlight module. A storage unit is connected via an SPI interface to maintain a defect compensation mapping rule base, supporting rule updates and calls with an update rate ≤1s.

[0044] Preferably, the FPGA chip is model EP4CE6F17C8. The built-in hardware acceleration logic of this chip can improve the speed of Gaussian filtering by about 2 times, which can adapt to the real-time processing requirements of 4K@60Hz image signals, without the problem of screen delay and stuttering, and can meet the processing performance requirements of daily TV viewing.

[0045] Preferably, the temperature sensor used is the DS18B20. This sensor is small in size, has an accuracy of ±0.5℃, and can output stable temperature data without additional calibration. It can fit into the narrow installation space of the backlight module and meet the integrated installation requirements inside the TV.

[0046] Preferably, the storage unit is model W25Q64 with a storage capacity of 8GB. This storage unit supports SPI standard serial read and write, and the read and write is stable and reliable. The stored data will not be lost after power failure. It is sufficient to store the defect compensation mapping rules of the entire partition and the basic backlight adjustment parameters, which can meet the storage requirements of this system. Moreover, this model of chip is inexpensive, highly compatible, and adaptable to most commonly used master control chip interfaces.

[0047] 2. Adaptive Partitioning Module: Employs an ARM processor with a 3.3V operating voltage and a 168MHz operating frequency. It connects to the image processing module via an SPI interface with a communication rate of 1Mbps. It incorporates a K-means brightness gradient clustering algorithm, written in C language, with a running efficiency of ≤50ms / frame. It receives image pixel brightness feature data, calculates the number, size, and shape of dynamic backlight partitions in real time, and outputs the partitioning results to the brightness threshold calculation module and the backlight driver module. The output format is binary data, facilitating subsequent module parsing.

[0048] Preferably, the ARM processor is the STM32F407ZET6. This chip has a built-in 1MB Flash program memory, 192KB SRAM, and abundant peripheral interface resources, which can meet the algorithm operation and data interaction requirements of the adaptive partitioning module. In addition, the chip has a wide operating temperature range and strong anti-interference ability, making it suitable for various application scenarios such as industrial and consumer electronics.

[0049] 3. Brightness Threshold Calculation Module: Integrated into the ARM processor, requiring no additional hardware, and implemented through software algorithms. It receives the partitioning results output by the adaptive partitioning module, calculates the mean, peak, and variance of brightness for each partition with a statistical precision of one gray level, queries the defect compensation mapping rule library, and calculates the optimal backlight brightness threshold for each partition using a preset formula with a calculation delay of ≤20ms. The output is sent to the backlight driver module, and the output signal is a 10-bit digital signal with a corresponding brightness threshold of 0-255.

[0050] 4. Backlight Module: Includes a light guide plate, side-lit LED strips, and 128 independent backlight driver units. The light guide plate is made of PMMA material and measures 1210mm × 680mm × 3mm. A reflective layer is placed on the bottom surface, and the light-emitting surface is divided into light-emitting areas adapted to the dynamic backlight zones, with an adaptation error not exceeding 0.1mm. The light-incident surface of the light guide plate has a frosted finish to improve light uniformity. The LED strips are side-lit LED strips, totaling 8 strips, each 1200mm long, using 2835 LEDs. The LED strip consists of 128 groups of 8 LEDs each. Each LED has a rated voltage of 3.3V, a rated current of 20mA, a luminous efficiency of 120lm / W, and a color temperature of 6500K. The light emitted from the LED strip faces the light-incident surface of the light guide plate, with a distance of 5mm between the LED strip and the light-incident surface to ensure uniform light incidence. The backlight driver unit uses a chip that drives one group of LEDs, supports PWM dimming, has a dimming frequency of 150Hz, a dimming range of 0%-100%, an operating voltage of 5V, and a power consumption of ≤0.2W / unit.

[0051] 5. Backlight Driver Module: Employs a dedicated backlight driver chip with a working voltage of 12V and a working current ≤4A. It connects to the brightness threshold calculation module via an I2C interface, receives the optimal brightness threshold signal (a 10-bit digital signal), and outputs the corresponding PWM dimming signal. Through 128 independent output channels, it independently controls the working current of each backlight driver unit, achieving differentiated backlight adjustment. The driver module's response time is ≤50ms, ensuring the real-time performance of zoned brightness adjustment.

[0052] 6. TFT Driving Module: Employs a dedicated TFT-LCD driving chip, supporting 4K resolution and a 60Hz refresh rate, operating at 3.3V. It connects to the backlight driving module via a GPIO interface, receiving the backlight brightness threshold for each zone. Through the gate and source driving circuits of the LCD panel, it fine-tunes the transmittance of the corresponding LCD pixels, with a fine-tuning range of ±5% to ±15% and an adjustment accuracy of 0.1%. This compensates for uneven brightness and ensures display consistency. The driving module connects to the LCD panel via an LVDS interface with a transmission rate ≥2.5Gbps.

[0053] 7. Feedback Detection Module: This module includes brightness sensors and power consumption detection chips. There are 16 brightness sensors evenly distributed on the back of the LCD panel, connected to the image processing module via an I2C interface. They have a sampling frequency of 15Hz, a detection accuracy of 0.1 lux, and a detection range of 0 lux-4000 lux, collecting real-time data on the actual backlight brightness of each zone. There are 128 power consumption detection chips, each connected in series in the power supply circuit of a backlight driver unit, connected to the ARM processor via an I2C interface. They have a sampling frequency of 10Hz, a detection accuracy of 1%, and a detection range of 0-1W, collecting real-time power consumption data from each backlight driver unit. The collected data is processed by the ARM processor and fed back to the brightness threshold calculation module for closed-loop optimization.

[0054] 8. Main control module: It adopts an ARM processor with a chip operating voltage of 3.3V and an operating frequency of 180MHz. It is connected to the image processing module, adaptive partitioning module, backlight driving module, TFT driving module, and feedback detection module. It is connected to the image processing module and adaptive partitioning module through the SPI interface, to the backlight driving module and feedback detection module through the I2C interface, and to the TFT driving module through the GPIO interface.

[0055] The main control module coordinates the working sequence of each module, executes closed-loop feedback optimization logic, and controls the stable operation of the entire system. It is also connected to a storage unit to store preset standard parameters, defect compensation mapping rule base, and historical operating data, and supports data retention even when power is off. It is also connected to a remote control receiver module, allowing users to adjust the energy-saving level via remote control. There are three energy-saving levels: high, medium, and low. Different energy-saving levels correspond to different preset dark / bright thresholds to adapt to different usage scenarios: the high energy-saving level corresponds to a dark threshold of 20 and a bright threshold of 120, with the highest energy saving rate; the low energy-saving level corresponds to a dark threshold of 40 and a bright threshold of 80.

[0056] Preferably, the storage unit model is W25Q128, with a storage capacity of 16GB, a 3.3V power supply, a working frequency supporting up to 168MHz, 192KB SRAM and 1024KB Flash, and rich peripheral interface resources. It can meet the design requirements of multiple interfaces for simultaneous connection and communication in this system, and can stably carry out the work tasks of module coordination, data storage and closed-loop logic operation.

[0057] Example 3: This embodiment provides a dynamic local dimming backlight energy-saving method and system adapted to a 27-inch full HD TFT-LCD monitor. The monitor has a resolution of 1920×1080, a refresh rate of 144Hz, and a color depth of 8bit. The monitor is mainly used for computer office and gaming scenarios, and has high requirements for response speed and display smoothness. The method and system are adapted and optimized based on Embodiments 1 and 2, as follows: Energy saving methods 1. Image Acquisition and Preprocessing: Input image signals are received through the DP 1.4 interface of the display, Gaussian filtering algorithm is used for noise reduction, weighted average grayscale conversion is performed, and pixel grayscale values ​​are extracted; physical properties and defect characteristics of the backlight module are acquired, including LED attenuation and light guide plate scratches, and a defect compensation mapping rule library is established with compensation parameters ranging from 0 to 8 to adapt to the backlight characteristics of small-sized displays.

[0058] 2. Adaptive Dynamic Zoning: Employs the K-means brightness gradient clustering algorithm, with a cluster size range of 8-128, an upper limit of 40 iterations, and a response time of ≤30ms. It can adapt to a 144Hz refresh rate and dynamically adjusts the number of zoning zones according to the screen type: 8-16 zones for office document screens and 64-128 zones for game screens. The zone boundaries are adapted to the light-emitting area of ​​the light guide plate to ensure that the screen is free of ghosting and zoning marks.

[0059] 3. The formula for calculating the brightness threshold of each zone is: X = (Y × 0.7 + Z × 0.3) + T; Among them, X is the optimal backlight brightness threshold, Y is the average brightness, Z is the peak brightness, and T is the compensation parameter. The threshold range is 0-255. In office scenarios, the focus is on energy saving, so the threshold is appropriately reduced by 10%-15%; in game scenarios, the focus is on display effect, so the threshold is appropriately increased by 5%-10% to ensure adaptability to different scenarios.

[0060] 4. Backlight Driver Adjustment: The backlight module adopts side-lit LED light strips, with 4 LED light strips, each composed of 64 groups of LEDs, for a total of 64 independent backlight driver units. The PWM dimming frequency is 200Hz, which can avoid flickering in game scenarios. The preset dark state threshold is 25, the bright state threshold is 110, the dark state zone PWM duty cycle is 0-5%, the normal state zone is 5%-35%, and the bright state zone is 35%-100%. The operating current is 3-15mA, balancing energy saving and response speed.

[0061] 5. LCD transmittance compensation: Fine-tuning range ±5%-±12%, in gaming scenarios, the difference between bright and dark areas is ≤3 lux to avoid screen ghosting; in office scenarios, uniformity is emphasized, with a transition difference of ≤6 lux to ensure clear text display.

[0062] 6. Dynamic feedback optimization: The sampling frequency is 20Hz, which can adapt to a 144Hz refresh rate. The PID parameters have a proportional coefficient of 1.2, an integral coefficient of 0.25, a derivative coefficient of 0.12, and a closed-loop adjustment response time of ≤50ms, ensuring real-time adaptation when the screen brightness changes and avoiding brightness lag.

[0063] Energy-saving system 1. Image processing module: It adopts an FPGA chip with a working frequency of 60MHz, connects to the DP 1.4 interface, has built-in noise reduction and grayscale modules, connects to 2 brightness sensors and 1 temperature sensor, collects defect and physical attribute features, and uses W25Q32 (4GB) storage unit to maintain the rule base.

[0064] 2. Adaptive partitioning module: Integrated into the ARM processor, operating frequency 168MHz, clustering algorithm running efficiency ≤30ms / frame, communicates with the image processing module via SPI, and outputs partitioning results to subsequent modules.

[0065] 3. Backlight Module: The light guide plate measures 610mm×340mm×2.5mm, made of PMMA material, with a reflective layer reflectivity of ≥94%. It has 4 side-lit LED strips, each 600mm long, with 2835 LED chips, arranged in groups of 8, for a total of 64 backlight driver units. The LED chips have a rated voltage of 3.3V and a current of 15mA.

[0066] 4. Other modules: The backlight driver module uses MAX16834, which can adapt to low-power scenarios, with an operating voltage of 12V and a current of 2A; the TFT driver module uses ILI9805; the feedback detection module uses 8 brightness sensors and 64 power consumption detection chips; the main control module uses STM32F429, which coordinates the timing of each module and supports users to adjust the mode through the OSD menu, including three modes: office, game and energy saving.

[0067] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. For those skilled in the art, the present invention can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for energy saving in dynamic zone backlighting of TFT-LCD, Its features This includes the following steps: S1. Image acquisition and preprocessing: The input image signal is acquired through the image receiving module of the TFT-LCD, and the image signal is subjected to noise reduction and grayscale processing. The pixel brightness features of the image are extracted. At the same time, the inherent physical property features and defect features of the TFT-LCD backlight module are acquired, and a defect compensation mapping rule library is established. S2. Adaptive dynamic partitioning: Based on the preprocessed image pixel brightness characteristics, a brightness gradient clustering algorithm is used to divide the TFT-LCD display panel into several dynamic backlight partitions. The number, size and shape of the dynamic backlight partitions are adaptively adjusted in real time according to the brightness distribution of the input image. Each dynamic backlight partition corresponds to an independent backlight driving unit, and the partition boundary is adapted to the light-emitting area of ​​the TFT-LCD light guide plate. S3. Calculation of brightness threshold for each dynamic backlight zone: For each dynamic backlight zone, the average brightness, peak brightness and variance of all pixels in the zone are calculated. Combined with the defect compensation mapping rule library, the optimal backlight brightness threshold of the zone is calculated. The optimal backlight brightness threshold meets the minimum power consumption requirement under the premise that the display effect of the zone meets the standard. S4. Backlight drive adjustment: Based on the optimal backlight brightness threshold of each dynamic backlight zone, the working current of the corresponding backlight drive unit is independently adjusted through the backlight drive module to achieve differentiated brightness output of different dynamic backlight zones. For zones with an average brightness value lower than the preset dark state threshold, the corresponding backlight drive unit is controlled to reduce the current until it is turned off. S5, Liquid Crystal Transmittance Collaborative Compensation: Synchronously acquire the transmittance parameters of the liquid crystal panel pixels corresponding to each dynamic backlight zone, and finely adjust the transmittance of the corresponding area liquid crystal pixels through the TFT driving module according to the backlight brightness threshold of the zone to compensate for the uneven brightness of the zone boundary. S6. Dynamic Feedback Optimization: Real-time acquisition of actual backlight brightness, liquid crystal transmittance and power consumption data of each dynamic backlight zone, comparison with preset standard parameters, and dynamic correction of brightness threshold and drive current of each zone through feedback adjustment algorithm to form closed-loop control.

2. The TFT-LCD dynamic zone backlight energy-saving system as described in claim 1, characterized in that, The backlight module's light guide plate is made of PMMA material, with a reflective layer on the bottom surface. The light strip is a side-lit LED light strip, and each backlight driving unit corresponds to a set of LED beads. It adopts PWM dimming mode with a PWM dimming frequency of 100Hz-200Hz.

3. The TFT-LCD dynamic zone backlight energy-saving method as described in claim 1, characterized in that, The brightness gradient clustering algorithm in S2 is the K-means algorithm, with a cluster size range of 16-256. The number of dynamic backlight partitions is automatically determined based on the changes in image brightness gradient, and the number of clustering iterations does not exceed 50.

4. The TFT-LCD dynamic zone backlight energy-saving method as described in claim 1, characterized in that, The defect compensation mapping rule base in S1 includes three defect types: LED chip attenuation, light guide plate scratches, and non-uniform refractive index of the backlight module. Each defect type corresponds to a different brightness compensation parameter, and the compensation parameter range is 0-10.

5. The TFT-LCD dynamic zone backlight energy-saving method as described in claim 1, characterized in that, The feedback control algorithm in S6 adopts the PID control algorithm, with a proportional coefficient of 0.5-1.5, an integral coefficient of 0.1-0.3, and a derivative coefficient of 0.05-0.

15.

6. A TFT-LCD dynamic zone backlight energy-saving system, characterized in that, The system includes: The image processing module is connected to the image receiver of the TFT-LCD. It is used to receive input image signals and perform preprocessing, extract pixel brightness features, collect physical properties and defect features of the backlight module, and establish and maintain a defect compensation mapping rule base. The adaptive partitioning module is connected to the image processing module and has a built-in brightness gradient clustering algorithm. It is used to divide the dynamic backlight partitions in real time according to the brightness characteristics of image pixels, and determine the number, size, shape and corresponding backlight driving unit of each partition. The brightness threshold calculation module, connected to the adaptive partitioning module, is used to statistically analyze the pixel brightness parameters of each dynamic backlight partition and, in conjunction with the defect compensation mapping rule base, calculate the optimal backlight brightness threshold for each partition. The backlight module includes a light guide plate, a light strip, and several independent backlight driving units. The light-emitting surface of the light guide plate is divided into light-emitting areas adapted to the dynamic backlight partitions. The light-emitting direction of the light strip is towards the light-incident surface of the light guide plate. The backlight driving units correspond one-to-one with the dynamic backlight partitions. The backlight driving module is connected to the brightness threshold calculation module and the backlight module respectively, and is used to independently control the operating current of each backlight driving unit according to the optimal backlight brightness threshold. The TFT driving module, connected to the backlight driving module and the TFT-LCD liquid crystal panel, is used to fine-tune the transmittance of the liquid crystal pixels in the corresponding area according to the backlight brightness threshold of each dynamic backlight zone. The feedback detection module is connected to the backlight module and the TFT driving module respectively, and is used to collect and feed back the actual backlight brightness, liquid crystal transmittance and power consumption data of each dynamic backlight zone in real time. The main control module is connected to all the above modules and is used to coordinate the working sequence of each module, execute closed-loop feedback optimization logic, and control the operation of the entire system.

7. The TFT-LCD dynamic zone backlight energy-saving system as described in claim 6, characterized in that, The image processing module uses an FPGA chip and has a built-in Gaussian filtering module and grayscale processing module. The adaptive partitioning module and brightness threshold calculation module are integrated into the ARM processor. The FPGA chip communicates with the ARM processor through the SPI interface.

8. The TFT-LCD dynamic zone backlight energy-saving system as described in claim 6, characterized in that, The brightness sensor of the feedback detection module is a digital brightness sensor with a detection accuracy of 0.1 lux and a sampling frequency of 10 Hz-20 Hz. The main control module also includes a storage unit for storing preset standard parameters, defect compensation mapping rule base and historical operation data. The storage capacity is not less than 16GB and supports data retention after power failure.