Semiconductor-based light emitting diode (LED) devices first appeared in the 1960s. Today, with the advances in materials, design and manufacture of LED devices, DfR is seeing a wide spectrum of LEDs that are cheaper, more colorful, more efficient, more intense, and more reliable. LED applications include signs and indicators, sensors, communication devices, displays, and increasingly solid state lighting and backlighting for TVs and monitors. The supply chain for LEDs can include producers of LED chips, packaging houses, LED driver chips and system integrators (e.g., LED light bulb). Large players in LED chip manufacture include Nichia, Philips, Osram and Cree.
LEDs provide unique advantages in solid state lighting due to their power efficiency and reliability. As an example, the Pharox 500 equivalent to a 60-watt conventional bulb from Lemnis Lighting (Figure 1) consumes 7 watts and lasts for ~25 years . The cost is currently projected to be under $40 and can go down to $10 in five years driven by demand and improvements in the electronics. Philips predicts that LEDs will make up 80% of the general illumination market by 2020.