LLD for LEDs

Frederick L. Hoffman, LLD (Hon), 1865–1946

This biographical sketch on Frederick L. Hoffman corresponds to the historic text, The Classic: A Plan for a More Effective Federal and State Health Administration, available at DOI 10.1007/s11999-009-1000-x. The article can also be accessed on the American Journal of Public Health web site at (http://www.ajph.org/cgi/reprint/9/3/161-a).

Nanophosphors for White Light Leds

Thermophotonics for ultra-high efficiency visible LEDs

The wall-plug efficiency of modern light-emitting diodes (LEDs) has far surpassed all other forms of lighting and is expected to improve further as the lifetime cost of a luminaire is today dominated by the cost of energy. The drive towards higher efficiency inevitably opens the question about the limits of future enhancement. Here, we investigate thermoelectric pumping as a means for improving...

Photon-Recycling for High Brightness LEDs

humble status indicators for domestic and industrial appliances. However, in the last ten years, the emergence of blue and violet emitters from the development of GaN, AlGaN, and InGaN materials [1] and improvements in efficiencies have led to high brightness LEDs suitable for a range of indoor and outdoor applications [2]. These devices have a significant advantage compared to conventional lig...

Green LEDs: The case for cubic GaN

Green LEDs formed from cubic GaN can have lower Auger losses, higher hole carrier mobility, greater optical gain and increased p-doping efficiency BY CAN BAYRAM FROM THE UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN The revolution in solid-state lighting is well underway. LEDs bulbs are now shipping in significant volumes, thanks to price tags that are far more competitive than they were just a fe...