By Alan C. Brawn CTS, DSCE, ISF-C
It’s safe to say that we live in the day and age of LED on a global scale. This tiny illumination technology has evolved and replaced more conventional means of visual mechanics in our lives. In the wonderful world of AV, LED is most noticeable in displays. It gained fame as a backlight for ubiquitous LCD displays, but today the most visible application is direct view LED (dvLED). While dvLED technology has been around since the late 1990s, it is only over the last few years that we have seen its popularity explode. The tipping point was the introduction of fine pitch dvLED displays for indoor applications. When the pixel pitch went from double digits down to 4mm, then 2.5mm and now sub 1mm, the individual diodes are almost invisible. It is not hard to see the appeal. You get saturated colors, high contrast, and high brightness in a bezel-free design. Add to that the fact that prices are declining due to higher volume production and the positive trend lines are easy to see.
From a purely technological point of view, the fundamentals of outdoor LED remain the same with slight variations in components provided by various manufacturers. For indoor fine pitch displays, a surface mount version permits the pixels to be closer together. The “sweet spot” of fine pitch dvLED is 4mm or less. For 2mm displays, you can stand 10 feet from a display and not see any pixels. The same can be true for 4mm displays but further distance is needed (perhaps 20 feet) to not see pixels. What most manufacturers are exhibiting at trade shows is their 1.5mm displays with a few showing fine pitch as low as .83mm. Just remember as the pixel pitch gets smaller, the prices go up. This begs the question of what’s next?
The answer is micro LED. As the name suggests this is a miniaturized version of the fine pitch surface mount design. Last year, Samsung introduced “The Wall” at 146 inches of width with a pixel pitch of less than 1mm. The interesting thing about micro LED advancements is that this may very well make it into luxury residences on the consumer side. Prototypes have been shown in the 75” range with a pixel pitch of 0.15mm. Other than the Wall, this is technology that you can count on as a differentiator in the near term.
Other advances that we are seeing is in the structure of the dvLED modules themselves is the ability to be tiled together to make displays of almost any size and aspect ratio. The central theme of these developments is to make installation easier. Some use wireless designs that eliminate the connecting cables while others use a “Lego-like” design to position the panels. There are also designated cabinets aimed at the rental and staging markets with a huge emphasis on serviceability to speed up the process of changing out modules on-site at venues.
In the last few months, we have also seen advances in video processing for dvLED displays. While some manufacturers use a generic processor, others are migrating to their own propriety designs. Since dvLED may or may not be addressed pixel by pixel relative to the resolution of a video source, video scaling is critical. There is also the increasing ability to handle 4K signals and source material and few companies have processor redundant designs for fail-safe operation. As one fails, the other processor kicks in.
The other interesting part of the dvLED revolution is the market itself, with an emphasis on who the “players” are. At InfoComm 2018 we saw a myriad of dvLED manufacturers on the show floor, many of whom we had never heard about. While this showed the global interest in the burgeoning market, it is the big names who are jumping on the bandwagon that is most telling. What do the flat panel giants like Samsung, LG, NEC, and Leyard-Planar, have in common? What do projector manufacturers like Christie, Barco, and Digital Projection have in common? The answer, of course, is dvLED. We are also seeing dvLED focused companies abound. There are Nanolumens, Silicon Core, Absen, and Unilumin to name a few. We even have US-based companies like Daktronics and Watchfire who are major players.
With all of these developments, it is an exciting time for the dvLED industry but keep in mind that the final part of the equation is the installation of the system. Unlike a standard VESA mount for a typical flat panel display, there are no standards for dvLED displays. The variables can be intimidating. It is not as simple as hanging a projector from the ceiling or a flat panel on a wall. There are size, weight, and serviceability to consider, not to mention the environmental and architectural factors that impact each project. Matching the display to the proper mount in a given project completes the picture and sets a good foundation no matter which dvLED display that is chosen.