Sandia LabNews

Optical Society Fellows


Hope Michelesen, Jeff Tsao elected Fellows of the Optical Society

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Hope Michelsen

Hope Michelsen and Jeff Tsao have been named Fellows of The Optical Society (OSA).

Hope, a distinguished member of the technical staff, is a researcher in Sandia’s Combustion Research Facility. She is honored specifically for pioneering contributions to the fundamental understanding of laser-radiation interactions with soot particles through laser-induced incandescence (LII), absorption, and scattering, and using LII to assess environmental impacts of carbonaceous particle.

“It is an unexpected honor for me to be elected to be an OSA Fellow,” says Hope. “It is an opportunity for me to remember and express gratitude for all of the great people I’ve worked with in developing the optical diagnostics for soot and black carbon that have brought me this honor. I have also been very fortunate to have stable funding through the DOE Basic Energy Sciences program to accomplish this work.”   

Hope’s research program focuses on developing and using optical techniques for studying the chemistry of combustion-generated particles inside the combustor and their impact on climate when released to the atmosphere. Her research experience includes gas-surface scattering experiments, atmospheric modeling, soot-formation studies, combustion-diagnostics development, atmospheric black-carbon measurements, and greenhouse-gas source attribution.

She received a bachelor of arts degree in chemistry from Dartmouth College and a PhD in chemistry with a minor in physics from Stanford University. She completed a National Science Foundation postdoctoral fellowship at Harvard University and worked at Atmospheric and Environmental Research Inc. before joining the technical staff at Sandia in 1999.

OSA was founded in 1916 and is the leading professional association in optics and photonics, home to accomplished science, engineering, and business leaders from all over the world. Through world-renowned publications, meetings, and membership programs, OSA provides quality information and inspiring interactions that power achievements in the science of light.  

 Fellow membership in OSA is limited to no more than 10 percent of the membership and is reserved for members who have served with distinction in the advancement of optics and photonics.

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Jeff Tsao

Jeff, a distinguished member of the techncal staff in the field of optoelectronics, was named an OSA Fellow in recognition of his "seminal, sustained contributions to solid-state lighting, and to its materials and optoelectronic device foundations.”

Jeff is one of 101 society members, including fellow Sandian Hope Michelsen (see above)  from 19 countries to achieve election.

Jeff’s career spans two national laboratories and brief stints in industry and academia. He has dedicated his career to optoelectronics, with more than two decades in solid state lighting.

In the late 1990s, when the efficiency of phosphor-converted white light LEDs was only a few percent, few researchers thought these glowing white rocks might someday be used for general illumination. However, Jeff and colleagues at Sandia and HP co-authored a paper that predicted efficiencies as high as 50 percent, and the enormous energy-savings potential that would be realized if achieved. The white paper is widely credited with inspiring SSL activity all over the world.

He later served on DOE committees that roadmapped possible paths for improved LED lighting, and came up with new ways of improving LED efficiencies and usefulness. Although his SSL work was largely programmatic and of a community service nature, the published parts have accumulated 1,750 citations.

Groups he managed earlier in his career were pioneers in optoelectronic materials and devices, including the VCSELs that are now revolutionizing 3-D sensing and autonomous driving. He has delivered more than 100 invited technical and general talks, with a large fraction related to SSL.

Wrote colleague Igal Brener in a supporting letter, “[Jeff] treats others unfailingly with respect and works as hard at his community’s success as at his own.”

Says Jeff: “Really, the Fellow award is also recognition of the many wonderful colleagues at Sandia and elsewhere with whom I have been fortunate to have worked, and of Sandia as an institution, whose ‘exceptional service in the national interest’ inspires the kind of forward-looking research in the national interest that the award was for.”