Product
In the command and dispatch center, stability and reliability are crucial core requirements. Weichuang believes that it is this point that gives COB technology absolute voice in the high-end small-pitch LED application market. Secondly, for audio-visual engineering, visual experience is also a key consideration. COB small-pitch technology has significant differences in picture quality compared with traditional surface-mounted lamp beads due to its chip-level packaging and full coverage of optical resin.
Although the high brightness of LED screens is a major advantage, it may become a disadvantage in indoor environments. The dizziness caused by high-brightness glare, high-frequency refresh, and the granularity of the lamp bead surface make LED screens prone to visual fatigue when viewed at close range and for a long time, which is difficult for many customers to accept. COB small-pitch technology can effectively eliminate the visual experience disadvantages of these traditional LED screens.
COB packaging technology achieves more excellent video optical performance through chip-level packaging, provides more comfortable and soft picture quality, and has no obvious pixel granularity, which is very suitable for close distance, indoor ambient light and long-term viewing conditions. Weichuang used "you will fall in love with COB at a glance" to describe this advantage, fully demonstrating the market experience advantage of COB products.
"Higher stability and reliability" and "better look and feel and comfort" are the realistic support points for COB small-pitch technology to become the standard for next-generation products. However, the advantages of COB technology go far beyond this.
Looking to the future, COB technology is leading a new breakthrough in small-pitch LEDs. Since the advent of small-pitch LED screens, the dot pitch index has continued to shrink. At present, domestic manufacturers have launched products with 0.7 and 0.8 mm pitches. However, these products have not yet achieved large-scale mass production and wide application, and have encountered limits and ceilings on the road to marketization. The further development of small-pitch LED technology must rely on the progress and innovation of basic processes, and COB technology is such a new advanced process.
First, COB small-pitch LED technology is conducive to controlling the bad pixel rate under extremely small pitch and a large number of lamp beads. Its bad pixel rate is less than one-tenth of the SMD surface mount process, which achieves higher reliability of the product and promotes the market application of high-pixel density products. COB technology is outstanding in this regard.
Secondly, COB technology using chip-level packaging technology essentially simplifies the process flow, directly replacing the two-step process of "first encapsulating lamp beads and then surface mounting" in the traditional process with packaging. Under the same application scale, especially when facing smaller and smaller pixels, its cost change is more controllable. For products with a pitch of P1.0 and below, the cost advantage of SMD surface mounting will be reversed, which is due to the simplification of engineering links and the advantages brought by direct large-scale packaging of LED crystals at the chip level.
Third, as the future development direction of the LED display industry, smaller crystal particles on small-pitch products are an inevitable trend. The advancement of LED light-emitting technology has made smaller LED crystal particles not only bright enough and generate less heat, but also meet the needs of large-screen display. Compared with the traditional "first lamp bead and then surface mounting" process route, COB packaging technology is more suitable for integrating smaller LED crystal particles.
When choosing a technical route, manufacturers must consider future development space. As LED display screens develop towards smaller pitches, SMD technology has encountered bottlenecks, and COB technology has obvious advantages in achieving small/micro pitches on LED display screens. Wetron holds this view. In 2017, Samsung strengthened the promotion of small-pitch LED screens in the digital film projection market, while Sony increased its promotion efforts in the production-level film and television market. Both industry giants support packaging-level technologies such as COB. From the perspective of product development, Sony demonstrated LED screen products based on MINI-LED particles, chip-level packaging, and only 0.5 mm pitch as early as 2012. The upstream LED industry in Taiwan also believes that starting from 2018, the "screen application" of MINI-LED products, including small-pitch LED screens and direct-type LCD backlight products, will enter an accelerated development stage.
In terms of the application of P1.5 COB and visualization solutions, in September 2017, the Ministry of Science and Technology received news: COB, as the future development direction of small-pitch LEDs, has obtained the project funding of the national "13th Five-Year Plan" key scientific research project-strategic advanced electronic materials·new display topics, and its main task is to break through the shortcomings and limitations of traditional small-pitch LED display technology.
With its significant advantages, COB technology has been selected by international manufacturers, recognized by the upstream industry, and supported by the government, which makes COB technology a key direction for the development of small-pitch LED products in the future. This is also the core reason why the industry calls COB the second-generation product of small-pitch LED screens.
Of course, even if it is a very excellent technology, COB small pitch cannot occupy the entire market overnight. Starting from the high-end market and gradually becoming popular, this process has been the path that surface-mounted small-pitch LED large-screen products have taken in the past six years. Now, it is the turn of COB small-pitch products to once again interpret this "market iteration" process.