Key trends in the development of LED lighting technology

LED lighting prices are expected to fall by 30% per year, with luminous efficacy approaching 200 lm/W by 2014. Many countries have also identified 2015 as a key milestone in their development of lighting policies, meaning that 2014 is likely to see a large-scale movement to replace traditional lighting. For example, Japan plans to raise the share of the general lighting market accounted for by LED lighting to 50% by 2015; South Korea also has a 2015 target of 30%; and China a 2015 target of 20%. The 2013-2014 period will be a crucial phase for laying the groundwork to achieve these 2015 targets; the LED lighting penetration rate is therefore forecast to hit 25.8% in 2014, with an output value of US$41.9 billion.

However, the industry has a long way to go before it can achieve those targets. Companies throughout the upstream, midstream and downstream LED supply chain are working on improving the quality of their products while reducing the costs, and Digitimes Research is keeping a close eye on the related impact on final products.

In terms of upstream LED components, manufacturers have continually pursued the goal of raising the luminous efficacy of LEDs. For example, Cree, the largest US-based LED manufacturer, had its 2W LED package products rated as high as 161 lm/W in 2011, higher than the maximum luminous efficacy of 133 lm/W for Nichia, the global LED leader by market share, and the 146 lm/W achieved by German giant Osram. However, it is Japanese manufacturer Toyoda Gosei that has positioned itself at the top of the market with the launch of a 170 lm/W LED component that delivers performance roughly two years ahead of the US DOE schedule for achieving such products. These products went on sale in early 2012.

Another challenge LED industry players are addressing is how to make LED products that are more easily used with mainstream electric grids. Most LEDs work on voltages that are radically different from that of mains electricity, resulting in a significant loss in efficiency. HV LEDs LEDs are one way of solving this problem.

In terms of LED package manufacturing processes, while COB was already in use in some sectors, falling LED prices have led more and more manufacturers to adopt it. Development efforts for COB technology have been focused on the need to increase luminous flux performance and decrease the volume of the device. Spotlights are one area where the potential of COB LEDs can be exploited, as the lack of ghosting on the subject for illumination means that optical performance is better than that of high-power LEDs.

Another type of process, which promises "freedom from binning" was developed by Philips for its Luxeon LED components. This method matches LED chips of different wavelengths with different phosphor formula in order to eliminate the different binning processes required for different LEDs. One advantage of this is that it to a large extent solves the problems of defective products and excess stocks, meaning that a much higher proportion of each batch of LED components can be used in the primary product range, i.e. LED lighting.

There have also been breakthrough developments in terms of capacitors, a key component affecting the lifespan of LED lighting products. Heat dissipation is another area where LED lighting manufacturers continue to make improvements, while on the downstream end product front, smart LED lighting systems are no longer limited to conceptual prototypes.

These various technological improvements should make a major contribution to increasing LED lighting uptake in the future, as they reduce the number of LED chips needed, reduce overall lighting costs, reduce power consumption, and improve LED usage rates.