Research On Key Technologies Of LED Intelligent Glass Display System

LED smart glass is widely used in indoor and outdoor activities because of its strong light permeability and good integration with buildings.The key technology research of LED smart glass can be roughly divided into front-end production process and back-end playback system.For the front-end production process,as the area of LED smart glass is getting larger and larger,the integration density of LED chips is getting higher and higher,and its production process and processing environment have higher requirements.Due to the limited accuracy of the equipment itself,the larger the machining size is,the larger the positioning error is,and the environmental temperature has a great influence on the positioning accuracy,The existing dispensing system based on MARK point positioning cannot guarantee the accuracy of the middle part of the glass.At present,the dispensing equipment used to improve the accuracy of LED smart glass dispensing often needs to be equipped with constant temperature and ultra clean processing workshop and marble clamping rail,which is extremely expensive in production cost.Based on this situation,this paper proposes an automatic identification and positioning compensation method based on pad image identification.For the back-end playback system,in order to better match various styles of buildings and attractions,there is a demand for shaped LED smart glass displays on the market.At this stage,the playback system cannot meet the needs of shaped LED smart glass displays.Based on this situation,this paper presents a playback control system for a special-shaped LED smart glass display.The error compensation system adopts the dual-core control mode of FPGA+ARM.ARM mainly completes the calculation of motion distance.It converts the calculation result into the pulse number and motion direction required by the motion control system and then sends the information to the servo motor motion control module.The motion control module will send a feedback signal to ARM after completing the motion control of the mechanical arm.ARM receives the feedback signal and then sends a start signal to the FPGA.The FPGA mainly completes the video image acquisition process and uses the method of location recognition and error calculation of pad as pixel matching method to complete the pad recognition and error calculation.By taking the pixel in the center of the image(FPGA uses dual port RAM to store video information,and stores pixels in the form of address self addition according to row and column order.Each pixel corresponds to an address,and the pixel in the image center can be taken out by calculating the middle address.)as the origin,the number of pixels from the four sides of the pad mark is counted to determine whether it deviates from the pad center and the direction and distance from the center,and then sends the eccentric distance calculation data to ARM.ARM converts this data into pulse number and direction information,and sends it to the motion control system again for position compensation.ARM receives feedback information from the motion control module,when the positioning error is less than the set value,the equipment starts to apply glue or patchaccordingly.The Special-shaped LED smart glass display playback system adopts the design method of master controller and slave controller,and the input coordinate mapping data is used to realize the display of LED smart glass screens with different specifications and shapes.For the special-shaped screen,firstly,the display area should be divided,and then the video image should be segmented to form a video stream.Because the number of control points of the special-shaped screen driver does not match the actual number of points.When mapping coordinates are generated,the virtual points are pre-buried by the host computer software to compensate Data that doesn't need to be displayed.So as to achieve the purpose of not affecting the part of the video data that needs to be displayed,thereby completing theplayback control of the special-shaped screen.The master controller adopts the dual-core structure of FPGA+ARM to complete the pixel address coordinate input,image access and optical fiber communication,and the slave controller uses FPGA as the main chip to complete optical fiber communication and data distribution.This paper presents and designs a positioning error compensation system based on image feature recognition of solder pad,which can solve the problem of low positioning accuracy in high-speed production of large-size LED intelligent glass through preliminary test verification.This paper proposes and designs a special-shaped screen playing system,which can meet the real-time display requirements of large-scale special-shaped LED intelligent glass through the laboratory,factory and field use verification.