Biophotonics Laboratory
California Institute of Technology


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Snow TsengDr. Snow H. Tseng
Assistant Professor of the Graduate Institute of Photonics and Optoelectronics and the Department of Electrical Engineering, National Taiwan University


PhD Electrical Engineering, Northwestern University 2005
MS Physics, University of Chicago 1997
BS Physics, National Taiwan University 1994

Research Interests

My research interest is on macroscopic biomedical light scattering problems in general. By numerically solving Maxwell's equations, the simulations are essentially idealized optical experiments in a noiseless environment. The numerical simulations are achieved by parallel computing simulations using the pseudospectral time-domain (PSTD) technique.

My current research projects include:
Optical Phase conjugation (OPC): This is a project I have been mostly working on with Yang, Meng, and Emily. By means of the virtual optical simulations, our goal is to explore electromagnetic properties that are difficult to analyze experimentally.

Cornea transparency: Why is the cornea transparent while the sclera is opaque? Can we analyze this problem based upon fundamental electromagnetism? This is a mystery that we are hoping to understand...


1. S.H. Tseng, Analysis of the cross-sectional width of the Optical Phase Conjugate Refocusing of Light Multiply Scattered through Macroscopic Random Media, IEEE Journal of Lightwave Technology. (in press)

2. S.H. Tseng, PSTD Simulation of Optical Phase Conjugation of Light Propagating Long Optical Paths, Optics Express Vol 17, 5490-5495, 2009.

3. S.H. Tseng, Optical characteristics of a cluster of closely-packed dielectric spheres, Optics Communications Vol 281, 1986-1990, 2008. doi:10.1016/j.optcom.2007.12.036

4. S.H. Tseng and C. Yang, 2-D PSTD Simulation of optical phase conjugation for turbidity suppression, Optics Express Vol 15, 16005-16016, 2007.

5. S.H. Tseng, Virtual Optical Experiment: Characterizing the Coherent Effects of Light Scattering through Macroscopic Random Media, Japanese Journal of Applied Physics Vol 46 (12), 7966-7969, 2007.

6. S.H. Tseng and Boyeh Huang, Comparing Monte Carlo simulation and pseudospectral time-domain numerical solutions of Maxwell's equations of light scattering by a macroscopic random medium, Applied Physics Letters Vol 91, 051114, 2007. doi: 10.1063/1.2767777

7. S.H. Tseng, A. Taflove, D. Maitland, V. Backman, PSTD Simulations of Multiple Light Scattering in 3-D Macroscopic Random Media, Radio Science Vol 41, RS4009, July 25, 2006. doi:10.1029/2005RS003408

8. S.H. Tseng, A. Taflove, D. Maitland, V. Backman, J.T. Walsh, Extracting Geometrical Information of Closely Packed Random Media from Multiply Scattered Light via a Cross-Correlation Analysis, IEEE Antennas and Wireless Propagation Letters Vol 5, pp. 91-94, 2006.

9. S.H. Tseng, A. Taflove, D. Maitland, V. Backman, J.T. Walsh, Interpretation of Noise-like Temporal Speckles for Clusters of Closely Packed Randomly Positioned Dielectric Cylinders, Optics Express Vol 13 (16), pp. 6127-6132, 2005.

10. S.H. Tseng, A. Taflove, Y.L. Kim, V. Backman, and J.T. Walsh, Simulation of enhanced backscattering of light by numerically solving Maxwell's equations without heuristic approximations, Optics Express Vol 13 (10), pp. 3666-3672, 2005.

11. S.H. Tseng, A. Taflove, D. Maitland, V. Backman, J.T. Walsh, Exact Solution of Maxwell's Equations for Optical Interactions with a Macroscopic Random Medium, Optics Letters Vol 30 (1), pp. 56-57, 2005 (and Optics Letters Vol 29 (12), pp. 1393-1395, 2004.) doi:10.1364/OL.30.000056