OLED technology is often referred to as the next “big thing” in lighting; some believing it to be even better than standard “inorganic” LED. Stephen Blackman, an engineer, artist and Founder & Chief Design Director of BlackJack Lighting, Chicago, is an industry-leading designer and thinker. His ideas have shaped and influenced how lighting fixtures look and perform in the United States and around the world. He gives here an insight into the present & potential scenario of the new generation OLED light sources.
General white lighting technology for OLED is available today as a very thin panel, some are round, or rectangular and some are square but most are about 3mm thick. The panels are available from only a handful of providers right now. LG Chem, Mitsubishi, Osram, and Philips Lighting are some that currently provide OLED lighting panels to the industry, although in limited volume. The technology is still being perfected. The rapid rate of introduction of newer and better performing OLED light sources is even more dramatic than standard LED light sources.
Unfortunately, right now OLED technology is not as efficient as its standard LED cousin. Available panels today are approximately 4” x 4” only and generate approximately 75 lumens. The cost is dramatically expensive and the average life span of the current OLED source is only about 10,000 hours.
Why would a manufacturer be interested in using this light source today? The answer is twofold. First OEM’s must examine the unique characteristics of the OLED panel to discover where it has advantages compared to traditional light sources and even to standard LED. Secondly, OEM’s must understand where we are in the OLED development cycle and how quickly we will have a high efficacy OLED panel at prices that will make it viable to a mainstream customer base.
Right now we see many custom architectural OLED fixtures with high numbers of low brightness panels in exciting and sculptural forms at trade shows and artistic installations as architectural focal points. The big question for many of us participating in the decorative and commercial fixture market is, “Can (OLED) do anything we can sell today?” The answer: yes and no!
OLED Exclusive Features
OLED is a panel source, not a point source of light like LED. The advantage of this is especially beneficial in general illumination applications where an even light distribution and low glare are important. Using a multiple panel light source creates a “surface of light” that can widely and evenly distribute light within a space. The wide luminous surface has a low surface brightness that can light up a room (with enough panels) but can also be easily viewed directly without blinding the observer.
Low heat is another achievement of OLED technology. The low input wattage and wide surface area of the panel creates very little heat and allows installation with only a small concern about creating a proper heat sink as with LED. This panel can be safely mounted to many different types of materials.
The feature that some argue makes current OLED panels most desirable is the thinness. While the performance of most OLED panels can be duplicated and even exceeded by standard LED’s and other light sources at the moment, none can duplicate the combination of low glare surface brightness, low heat and thinness.
Add the ability to be easily dimmed, and certain versions are available that can provide controlled colour changing capabilities and you have the recipe for exciting designs.
While OLED technology is advancing, certain standards are starting to appear. OLED lighting panel sizes are starting to emerge that are becoming common to several of the OLED panel suppliers. Standardization in module size helps create fixture platforms that can be updated at a later date with the latest and most efficient panels.
Fortunately OLED panel makers and innovators, like LG Chem, are focused on producing panels with higher output and a longer life. LG Chem projects its panels will reach 135 lm/W and 40K hours by 2015. Philips also is projecting its panels will deliver up to 140 lm/W. The development roadmap for many OLED panel developers includes exploiting characteristics that are different than traditional light sources but unique to OLEDs, such as flexibility and transparency of the light source panel. However, the most interesting characteristic that fixture makers and designers will watch is cost.
OLED lighting technology is on the United States Department of Energy’s road map of emerging Solid State Lighting technologies and given its predictions, it is going to be an incredible lighting source.
According to the US DOE’s Solid-State Lighting R&D Manufacturing Roadmap, the OLED milestone goal for the industry is to make OLED cost-competitive with other technologies. This is a daunting goal, considering the current price of an OLED panel around $1,500 per klm is intended to be brought down to almost $20 per klm by 2020. However LG Chem feels that it will be able to provide the performance goals and drastically reduce the panel pricing by investing in their production processes and high volume production lines.
To judge the credibility of this claim, one can look at the rate of cost reductions and performance improvements that we have seen in the last ten years of standard “inorganic” LED manufacturing. The current OLED development roadmap shows that OLED panels are on track to achieve the same cost reduction and performance improvement rate, that too in less time.
Most likely, in 2014 we will see OLED panels continue to improve in efficacy, even as costs will continue to fall. Although we are still at an early stage, the OLED development rate is generally keeping the pace of cost and performance improvement.