Technology | Feb 01, 2010

Thermally Activated Degradation of Phosphor-Converted White LEDs

Figure 8 - Optical images of electrical aged device (top), thermal aged device (center), and the cross section of the electrical aged device, along cathode-anode direction. The increasing performances and long lifetime of High Brightness LEDs are still limited by the high temperatures involved. This work shows the results of several accelerated lifetime tests on 1W white LEDs. Two different tests have been carried out: a pure thermal storage at different temperatures and an electrical aging obtained by biasing the LEDs. The impact of high temperatures has been evaluated in terms of flux decay, chromatic properties modification, increase of forward voltage and thermal resistance. A picture of the main degradation mechanisms detected has been provided in detail. Read more »

Technology | Jan 30, 2009

For Refrigeration Problems, a Magnetically Attractive Solution, Maybe for SSL Cooling too

HOW IT WORKS: Conventional and magnetic refrigeration cycles use different physical effects to cool things off. [Top] When a gas is compressed (2), it heats up, but if it is cooled and then allowed to expand (3), its temperature drops much lower than it was originally (4); this principle keeps food in your home refrigerator cool. But a magnetocaloric material [bottom] heats up when magnetized (b); if cooled and then demagnetized (c), its temperature drops dramatically (d). Electricity-guzzling cooling systems could soon be a lot smaller, quieter and more economical thanks to an exotic metal alloy discovered by an international collaboration working at the National Institute of Standards and Technology (NIST)’s Center for Neutron Research (NCNR).* Read more »

Technology | Sep 10, 2008

Optek - Thermal Management - Introduction

Optek presents the research on heat management. Read more »

Technology | Aug 13, 2007

New technology has dramatic chip-cooling potential for future computers - a solution for LED lighting too?

purdue_research_cooling-jpg Researchers have demonstrated a new technology using tiny "ionic wind engines" that might dramatically improve computer chip cooling, possibly addressing a looming threat to future advances in computers and electronics. Read more »

Technology | Jun 04, 2007

New method to cool electronics, harness waste heat and sunlight

Orest Symko demonstrates a device for a promising new technology for capturing heat now wasted during industrial processes and turning it into electric power. Here, Symko uses a battery to heat the device in his hands. The device changes the heat to audible sound, and then into an electric current that makes the light bulb glow. University of Utah physicists developed small devices that turn heat into sound and then into electricity. The technology holds promise for changing waste heat into electricity, harnessing solar energy and cooling computers and radars. Read more »

FEATURED

Nationstar Overall Layout in UV LED Market

Nationstar Overall Layout in UV LED Market In August 2018, Nationstar set up the Non-visual Light Source Business Division, focusing on IR LED, UV LED, animal and plant lighting. Nationstar has been fully laid out on UVA/UVB/UVC. Since 2016, Nationstar has launched near-ultraviolet LED, deep-ultraviolet LED and modules, with wide wavelength ... Read more »

EDITORIAL

High Conductive Foils Enabling Large Area Lighting

High Conductive Foils Enabling Large Area Lighting Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP as one of the leading partners for research and development for surface technologies and organic electronics and Sefar AG, a leading manufacturer of precision fabrics from monofilaments, developed a roll-to-roll ... Read more »

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