A quick visit to your local stockist of high end televisions and monitors is all that is required to notice the latest technology trend – ultra-slim LED displays are definitely the next big thing. But what are they and how do they work?
Essentially, LED TVs aren’t really LED TVs at all. They are LCD TVs with an LED backlight system. Conventional LCD displays use a fluorescent light source in the Back Light Unit (BLU). I don’t think that I have ever used so many acronyms in a paragraph in my life before.
Now, because a BLU for an LCD TV (there I go again) forms part of a relatively expensive piece of hardware and because that hardware is designed to be closely watched, the quality and the durability of the BLU is extremely important to the manufacturer. Big brands such as Panasonic, Apple, Samsung and LG are all staking their reputations on these vital components. For this reason, BLU development benefits from enormous investment.
Now, the main reasons for the development of LED BLUs are efficiency, reliability, response time, packaging and uniformity. I don’t know this as a fact, because I wasn’t present at the product development meetings, but as these are the main selling points for the finished products, I’m fairly confident that they were significant considerations.
Two different configurations of LED backlighting were developed. The first is direct lighting, where an array of LEDs shine onto a diffusion layer. In order to make the light on the diffusion layer uniform, the LEDs must either be small and close to the diffusion layer, or large and further away. Using large quantities of tiny LEDs is complex and has a high number of potential points of failure. Using a smaller number of larger LEDs requires more space and results in a thicker BLU. The second option, edge lighting, uses amazingly efficient light guides to direct light from LEDs situated around the edge of the lit panel onto a diffusion layer. Edge lit panels can therefore be very thin, but are still very powerful and the light is very evenly distributed.
It would be rather tricky to justify the same level of investment to perfect a light source for general purpose lighting. That is probably why we are only just moving away from Edison’s original electric light bulb design.
However, the R&D has been done and as a remarkably happy coincidence, we now have a rather amazing new light source to work with. We are now launching edge lit panel grid lights, suspended panels, shelf panels and a whole raft of other incredible products based on this technology.
We are also looking for new projects where we can integrate the edge lit LED panels into other products and structures at the point of manufacture – at only 20mm thick, they can be built into furniture, mirrors, walls and kitchen equipment in domestic homes, as well as in commercial applications such as vehicle interior lighting, emergency signage, advertising and display. The possibilities are endless – we really do believe that this technology is the first stage in a process of major change in the way that we go about lighting our world.
