Research And Implementation Of Gray Algorithm In High Definition LED Control System

With the development of electronic technology,LED display has been used more and more widely because of its high brightness,large angle of view,flexible and variable area,but the demand for its performance is also higher and higher.The gray levels,visual refresh frequency,brightness efficiency and gray display uniformity have become a inter restricting relationship,because the shift clock frequency can't be improved indefinitely and the minimum pulse width can't be reduced without limit,when LED display control system uses the PWM algorithm to control gray.At present,the gray control algorithm,such as the weight of the light off and the mixed method,the global synthesis of the brightness of the PWM control method can't meet the requirements of high gray,high refresh rate,high brightness.Therefore,we need a new algorithm of gray level modulation,which can meet the requirements of high brightness,high refresh and high gray level of LED display.Therefore,we need a new algorithm of gray level modulation,which can meet the requirements of high brightness,high refresh and high gray level of LED display.In order to improve the refresh rate and the gray levels of LED display,this paper improves and optimizes the gating pulse width modulation(GPWM)algorithm,and proposes a method to combine the line break with the high and low gray level through the study of LED gray scale modulation algorithm.A row of gray level implementation process is divided into K sub modulation process.After the sub field is divided,each sub modulation process is evenly distributed.In each sub modulation process,the sub field of high and low gray level sort.Then,this paper introduces the architecture of the high definition LED control system based on FPGA as the main control chip,the realization of communication and storage module,and the realization of the algorithm in the system.Finally,the model and algorithm are verified by the concrete engineering practice and simulation.The experimental results show that compared the improved gray scale control algorithm and the traditional pulse width modulation algorithm,using a combination of methods with scattered line scattering and gray level,so that the LED display has a gray distribution more uniform,and the gray level under the same visual refresh rate increasedmore than 4 times,or the same refresh frequency the gray level in the visual improvement of at least 2bit.The practice proved that in the 1/8 scan on the screen,adding after gray algorithm LED display visual refresh rate increased from 420 Hz to 1680 Hz,or gray series is increased from 14 bit to 16 bit,and the gray display uniform,greatly improving the display effect of LED display.