Dr. Tso Yee (T.Y.) Fan is a senior staff member of the Laser Technology and Applications Group, pursuing research in solid-state lasers, laser beam combining, and nonlinear frequency conversion.

Fan is widely recognized for his work in diode-pumped solid-state lasers, particularly Yb:YAG, in cryogenic cooling of solid-state lasers to enable power scaling, and in developing both wavelength beam combining and coherent beam combining for large-count laser arrays.

Fan has authored or coauthored numerous papers and conference presentations, and served on conference committees, including as chair, and was an elected member of the Board of Governors for the IEEE Lasers and Electro-Optics Society. He has also served as topical editor in lasers for Optics Letters and as a division editor for Applied Optics. He is a Fellow of the Optical Society of America and a Senior Member of the IEEE. He was awarded the MIT Lincoln Laboratory Technical Excellence Award in 2009, was a co-recipient of the MIT Lincoln Laboratory Best Invention Award in 2011, and was a co-recipient of the Berthold Leibinger Innovationpreis, First Prize, in 2012.