- By Christos Sarakinos, Engineer, Future Lighting Solutions -
Since power LEDs were first introduced by Philips Lumileds in 1999, entrepreneurs and environmentalists have envisioned a world in which the majority of lighting was solid-state based. Owing to their seemingly infinite lifespan and the revolutionary design possibilities their compact size enables, power LEDs have gained widespread acceptance by makers of traffic, emergency vehicle, portable and niche medical products.
Luminaire manufacturers by contrast have been more reserved, patiently awaiting a rival to traditional technologies, one with higher efficiency and proven reliability. In response to this, some power LED manufacturers have regularly issued press releases announcing exciting performance records – possible only in the confines of their laboratories.
Each time, luminaire designers have asked in unison: Are we there yet? Figure 1 – Philips Lumileds’ industry-leading power LEDs, the LUXEON K2 and the LUXEON Rebel
One indication comes from the increase in worldwide concern for environmental issues. The evergrowing list of countries, states and provinces that have tabled proposals to ban incandescent bulbs within the next decade include: Cuba, Venezuela, Australia, California (USA) and Ontario (Canada).
Much of the “ban-the-bulb” legislation focuses on the increased use of compact fluorescents, mainly due to their high availability since the 1970s. Given their slow startup, the inability to dim them, the electronic interference they cause, as well as the mercury contained within, consumers remain reluctant. An alternative is needed.
When considering the viability of a light source, the following factors are critical:
• System efficiency
• Quality of light
• Lifetime and reliability
The following sections examine each of these factors, explain their relevance, and compare the power LED with traditional technologies.