Small spacing LED screen production process requirements
With the economic market demand and micro-pitch LED display technology, rapid progress and maturity, micro-pitch LED display point spacing is getting smaller and smaller, and now the market has introduced P1.4, P1.2, P0.9 and other micro-pitch LED Display, and widely in video conferencing, command and control, monitoring center, radio and television media and other fields. In the past few years, micro-pitch LED display of high-definition display, high refresh frequency, seamless splicing, good cooling system, easy disassembly and flexible, energy saving and environmental protection features have been widely known by the industry users, but further To micro-spacing LED screen specific technology, the general public is rarely known, "only know that I do not know the second", the lack of professional knowledge, led directly to the emergence of the purchase of blind spots.
From the technical level, the smaller the distance between the micro-pitch display of the LED placement, assembly, splicing process and the higher the requirements of the structure. This article will be micro-pitch LED display technology to analyze the technology, allowing users to more thorough understanding of micro-pitch LED products.
1, packaging technology:
P2 above the density of the display screen generally use 1515,2020,3528 lights, LED pin shape using J or L package. Lateral welding pin, the welding area will be reflective, poor ink effect, it is necessary to increase the mask to improve the contrast. Density further improved, L or J package can not meet the application requirements, must be used QFN package. This process is characterized by no side of the welding pin, the welding area without reflection, so that the color effect is very good. In addition, the use of all-black integrated design molding, the screen contrast increased by 50%, showing the application of quality effects compared to the previous display even better.
2, welding process:
Reflow soldering temperature rise too fast will lead to uneven wetting, will inevitably cause the device in the process of wetting imbalance caused. Excessive wind circulation also causes displacement of the device. Try to choose more than 12 temperature reflow soldering machine, chain speed, temperature rise, the cycle of wind as a strict control project, that is, to meet the reliability requirements of welding, but also to reduce or avoid the device shift, try to control the scope of demand. Generally, the 2% range of pixel pitch is used as the control value.
3, box assembly:
The box is made of different modules made of stitching, the flatness of the box and the gap between the modules directly after the overall effect of the box assembly. Aluminum processing box, cast aluminum box is the current application of a wide range of box type, flatness can reach 10 mesh between the module between the gap between the two modules to assess the distance between the pixels, two pixels are too close after the light Line, two pixels too far will lead to dark lines. Assembly before the need to measure the calculation of the module patchwork, and then use the relative thickness of the metal as a rule with the pre-insert to assemble.
4, screen body assembly:
Assembly of the finished box needs to be assembled into a screen before you can display the fine picture, video. But the box itself size tolerance and assembly of the cumulative tolerance of micro-spacing display assembly effect can not be ignored. Between the box and the box of the recent device pixel spacing is too large, too small will lead to show dark lines, bright lines. Dark line, bright line problem is now micro-spacing display can not be ignored, need to be anxious to overcome the problem. Some companies through the paste 3m tape, the box fine adjustment nut to adjust to achieve the best results.
5, printed circuit board technology:
With the development trend of micro-interval display, 4-layer, 6-layer board is used, printed circuit board will use micro-hole and buried hole design, printed circuit graphics wire fine, narrow micro-pitch, processing used in Mechanical drilling technology can not meet the requirements of the rapid development of the laser drilling technology will meet the micro-hole processing.
6, printing technology:
Too much, too little amount of solder paste and printing offset directly affect the micro-distance display lamp welding quality. The correct PCB pad design needs to communicate with the manufacturer after the implementation of the design, the screen size and printing parameters of the correct or not directly related to the amount of printed solder paste. General 2020RGB device with 0.1-0.12mm thickness of the polished laser steel mesh, 1010RGB the following devices recommended 1.0-0.8 thickness of the steel mesh. Thickness, opening size and tin in proportion to increase. Micro-spacing LED welding quality and solder paste printing is closely related to the thickness of the detection, SPC analysis and other functions of the use of presses will play an important role in reliability.
7, placement technology:
Micro-pitch display of the RGB device position of the subtle offset will lead to screen display is not uniform, is bound to require a higher precision placement equipment.
8, the system card selection:
Micro-spacing display bright and dark lines and uniformity, color difference is the difference between LED devices, IC current differences, circuit layout differences, assembly differences, such as the accumulation of criticism, some system card companies through software correction can reduce the brightness and brightness, all. Choose high-performance system card, micro-pitch LED display for brightness, color correction, making the display to achieve better brightness and chroma uniformity, and achieved good display.
"Meet the good thousand, win-win horizon" to meet customers on the precision display, energy efficient, stable and reliable, the ultimate quality of micro-spacing LED display products are micro-spacing LED manufacturers production requirements, only to achieve the relevant raw materials and production technology control, Micro-spacing LED display in order to bring users more high-end display.