Black is the new black

What’s next for LED technology? It has conquered the high end rental market, is finding its way into the foyers of banks and is now making a move into commercial signage. InAVate talks to the manufacturers and discovers that….

LED display technology is an essential part of the arsenal of an AV designer and has been for several years. In situations that call for large, high resolution displays or displays that have to be visible under bright conditions, there is still nothing to match LED.

The display manufacturers themselves have played on this strength, vying with each other for even increasing resolution, and brightness to produce better and better video displays. Pitches (the space between individual pixels) have fallen with each generation of products to the point where several of the leading manufacturers are able to offer screens with 3mm pixel pitch. From viewing distances greater than a handful of metres these screens look just as good as plasma or LCD displays, only much larger and brighter.

At the same time, LED manufacturers have been improving the quality of the basic unit through advances in semiconductor technologies. The LEDs themselves have become brighter, cooler, cheaper and generally more efficient. These improvements have been necessary, though, as display producers become ever more demanding in the environments and applications for which they use the LEDs.

But where next? Does pitch continue to the be the headline figure, or are display manufacturers at the bottom of the spiral of diminishing returns in terms of squeezing more LEDs into smaller areas? What is the new battleground for the next three or four years?

The verdict from the manufacturers themselves is pretty unanimous. The rush for pitch is over. Where exactly it has stopped depends on the application and who you talk to. Lighthouse Technologies’ Managing Director is Mark Chan. “I personally believe that once you get below 4mm you are approaching the point where your returns are minimal. Between 3mm and 4mm products there is a power of two difference in price.”

And it is price is the key word at this end of the market. The main consumers of the very high end products are the rental and staging companies, who supply LEDs to corporate events, such as the IAA show, or live music extravaganzas. Russell Hartwell, Mitsubishi’s Diamond Vision Sales Manager commented: “3mm pitch has not worked out commercially for rental companies. At the 4mm point the cost becomes more manageable in terms of man-hours required to get the screen looking right in a rental situation.”

Marty Brown from Daktronics agrees: “It’s just so happening that the price point of the 3mm products is higher than it needs to be to be accepted by the market.”

Away from rental there is still a small niche for 3mm products. In order to achieve HD resolution, in a screen of a reasonable size, you need your pixels as tightly packed as possible. German telecomms company T-Com had Europe’s first native HD LE display installed at their Bonn HQ. It consisted of 18 sqm of Mitsubishi’s IDT3 3mm product at a resolution of 1920 x 1080.

For most applications even 4mm screens are probably a little too expensive. Barco’s Chris Colpaert, Director of Product Management for Media and Events, believes that 6mm pixel pitch is both sufficient and cost effective and that the shift to 4mm will be relatively slow compared to the transitions that have happened in the past.

So if everyone is agreed that 3mm is as low as the rental companies will limbo, where will the innovations come from? Image quality appears to be the new mantra, in terms of colour-reproduction, contrast and also the mechanical stability of the LED modules. Black it seems really is the new black, as most of the major players now offer a solution to deliver improved blacks. Hibino has a Black Face product in 4 and 6mm pitches, named 4B and 6B. Mitsubishi’s Black Package 4 and 6 mm products were used at the IAA show in Frankfurt and Lighthouse has a rental product called R4-B (rental, 4mm, black) in the works. Barco’s NX-4 and forthcoming NX-6 products both play to the demand for better blacks and therefore greater contrast.

Other innovations include more physical considerations. Packing LEDs more closely together increases the current density of the modules and therefore the amount of heat they put out. Despite the improvements in the efficiency of the LEDs this still means more cooling is required, and that means more fans. However fans are noisy beasts so the likes of Lighthouse, Barco and Daktronics are hard at work developing quieter and more efficient cooling systems. Mark Chan again: “Our approach to design has become more holistic. We aren’t just considering the LEDs themselves but also the thermal issues and over all weight of a wall. Shipping rental systems around the world is very expensive.”

Another upshot of increased LED density is an effect known as colour shift. “When you are viewing a very tightly packed wall from a wide viewing angle then some LEDs block the light from other LEDs,” explained Daktronics’ Brown. “We can’t change the LEDs themselves, but we can control the pattern in which we apply them. We can also control the louvre and plastics design on the face of the module.”

The market for LED displays has changed a lot since they first became available. Traditionally LED was an expensive solution and reserved for those who could afford it – top league sports clubs, multinational corporations and, on the rental side, car manufacturers. According to Lighthouse’s Chan, the rental companies are still the early adopters of new innovations because their business models are set up to absorb the significant investment made in stock. The recent IAA show in Frankfurt showed that the demand for LED by stand designers remained undimmed with almost every single stand featuring an LED display of some shape or another.

However away from the bleeding edge, new possibilities are emerging. “Networks of outdoor LED screens, properly managed and run has been the holy grail of the LED industry for about 10-15 years,” said Mitsubishi’s Hartwell. Barco’s Colpaert agrees. “The digital signage market is very popular now, along side the traditional rental and motor show market.”

Kris Delafontaine, Marketing Manager for Hibino believes that the Motor show business will remain one of the most important sectors, however he also sees that the fixed installation market in Europe holds a lot of promise for his organisation.

As far as Daktronics is concerned things are different. “One area that seems to be exploding is media facades,” said Brown. “These are lower resolution presentations, both indoor and outdoor, and the products used for them are typically puck (individual pixels) and stick or mesh products. More creativity is possible, and the market likes the transparency because it doesn’t obscure the architecture that already exists. Very often they are used less for video and more for text or colouring effects.”

New product development by the manufacturers is, logically, following their opinions of where the most important applications lie. Daktronics is pursuing development of its line of creative LED products, the Pro-Pixel, with a line of stick type solutions and possibly then mesh products. That in itself throws up further requirements for innovation. “These systems also require a different type of control, so we’re developing in parallel our next generation of controllers,” explained Marty Brown.

Barco and Hibino were both pretty tight-lipped on future plans but Barco’s Chris Colpaert would say that they have a new outdoor display for the digital signage market planned for 2008. Hibino are clearly focused on the European fixed installation space next year with plans for a new range of installed product.

Russell Hartwell of Mitsubishi was a little more forthcoming: “Our new black package screen is very important, but we also have a product we’re calling Resolia on the way. This is an LED screen that fills the gap between display technologies such as Plasma and Projection and larger bespoke LED screens. It’s a 140” LED screen that’s ready to plug and play out of the box, for fixed installation or rental applications. Using true 4mm pitch it gives us a resolution of 748 x 448.”

So, there’s plenty going on in the land of LED, but is there any pressure from other technologies? Elsewhere this month Tim Kridel is looking at one of the pretenders to LEDs crown for large billboard displays, but do the LED players really see it as competition? Not really it would seem. The main stumbling block for any technology hoping to out-do LED is brightness and the verdict is unanimous – the new technologies such as Magink are not up to the mark. Daktronic’s Marty Brown summarised things nicely: “To date there are no technologies threatening LED within the space in which it operates. We don’t see that coming for a while, it seems that the ink technologies, which we’ve all read about aren’t coming along at the pace we thought they might. I don’t even consider those to be comparable products.”

Quite to the contrary, a couple of the manufacturers have their eyes on markets that have traditionally been the preserve of other technologies. Mitsubishi’s Resolia, which they hope to demonstrate at ISE, is pushing towards the space occupied by things such as rear projection or bezel-less plasma. Lighthouse Technologies’ Chan believes that in light environments where viewing distance is 3-4 metres there is real competition between LED and the traditional technologies.

It’s pretty apparent that there’s no end in sight to the ubiquity of LED in day to day use. Whilst the likes of the motor exhibitions and headline rock concerts showcase the very latest in technology, there is also an inevitable creep as these expensive developments become cheaper and are applied to more commercially based products. Whilst the technologies used in the “new black” may not be immediately cheap enough to be suited to digital signage or other mass use applications, you can bet that within two or three years they will be and that the next best thing will be top of the tech tree for use by the XL Videos and Procons of this world for their automobile clients.

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