Design Of Control System For Automatic White Balance And Color Temperature In Laser Display

With the development of the times and the progress of science and technology,laser display has developed rapidly with its advantages of high color saturation,large color gamut,high resolution,high brightness and adjustable color temperature.It has become a new generation of laser display technology.In the laser display technology,the light source of the laser display is composed of three primary color laser modules,and the optical power of the three primary color light sources is changed due to the factors of temperature and aging during its use,which leads to the change of the color temperature of the laser display.In order to achieve automatic white balance and color temperature adjustment of the laser display device,a high-stability automatic white balance and color temperature control system is developed to study the signal acquisition and filtering technology of optical feedback to ensure accurate signal acquisition and accurate current control.The optical power PID integrated regulation system to ensure the stability of light output.The system to 32-bit ARM core STM32 system for the hardware core,including:1.white balance laser power solution module.The calibrated colorimeter measures the color coordinate value of the white field of the laser display device projected on the screen as a reference,the input optical power solution module is used as the correction value of the light machine and the light source system and is stored in the module of each display device,The built-in algorithm is used to automatically calculate the power ratio of the three primary colors needed to achieve the preset white-field color temperature under the light source coupling system and the optical projector projection system.2.laser display light source module power feedback control system.The incident light intensity is measured in real time through a calibrated photodiode arranged inside the light machine and the output laser power(P)of the light source module and the forward voltage(V)and the forward current(I)of the light source module are recorded.,Form a PIV record for each module and monitor the working status of each module in real time and issue a failure warning to the failed module.3.laser display light source module high stability power control system.Combined with the power ratio of the three primary colors calculated by the power solution module and the PIV parameters measured by the power feedback system,the optimal control objectives are set,the operating current of each light source module is used as a control variable,and the laser power is controlled by self-tuning PID current control Fast convergence and reduce control errors,to ensure the stability of the dynamic adjustment process,to avoid the light source flicker caused by power jitter phenomenon.To ensure the life of the laser under the premise of improving the utilization of light source module.In the whole thesis,the major scientific problem to be solved or the key technology is the realization of high-precision laser power feedback.In order to ensure the high light energy utilization rate of the laser display light machine,the light required for the laser power feedback sampling needs to have as little impact on the light machine efficiency as possible while reducing the measurement error caused by the nonuniformity of the tristimulus laser light.In the high-precision laser power feedback,it is necessary to control the temperature very stable,while the laser module current and voltage monitoring to ensure the normal operation of the laser module to improve the stability of the laser display system.