July 4, 2011

[singlepic id=980 w=320 h=240 float=right]Solid-state lighting is currently based on light-emitting diodes (LEDs) and phosphors.  Solid-state lighting based on lasers would offer significant advantages including high potential efficiencies at high current densities. Light emitted from lasers, however, has a much narrower spectral linewidth than light emitted from LEDs or phosphors.  Therefore it is a common belief that white light produced by a set of lasers of different colors would not be of high enough quality for general illumination.June 22

In a paper just published in a special “Optics in LEDs for Lighting” issue of Energy Express (a supplement to Optics Express), Sasha Neumann (graduate student at the University of New Mexico), Jon Wierer (EFRC scientist), Wendy Davis (scientist at NIST Gaithersburg), Yoshi  Ohno (scientist at NIST Gaithersburg), Steve Brueck (Professor at the University of New Mexico and EFRC external partner), and Jeff Tsao (EFRC scientist), tested this belief experimentally.  They found the opposite to be true:  in terms of color rendering quality, white light from a four-color (RYGB) laser setup is virtually indistinguishable from white reference light, including that from an incandescent lamp and three phosphor-converted LEDs (warm white, neutral white and cool white).  This result paves the way for the use of lasers in solid-state lighting.