Speaker：Shih-Chi Chen, the Chinese University of Hongkong
Invited by：Prof. Yuan Jing
Time：10:00-11:30, July 25, 2018
Venue: A101
Abstract:
I will present our recent work on femtosecond laser manipulation based on digital micromirror devices (DMD) and binary hologram; and its applications in developing the next-generation two-photon excitation microscopes as well as parallel laser fabrication systems. The DMD-based pulse/beam shaper can arbitrarily shape a femtosecond laser at a speed of up to 30 MHz and 32 kHz respectively, around 3 orders of magnitude faster than any existing methods. The DMD beam shaper is integrated with a custom-built laser scanning two-photon microscope to realize new imaging functions including multi-depth imaging, arbitrary surface imaging, and random-access scanning for real-time in vivo biological studies. In the second part, I will present a temporal focusing-based laser fabrication system, where the spectrum of the femtosecond laser pulse is first spatially separated by a DMD, serving simultaneously as a diffraction grating and a programmable binary mask. After collimation, an objective lens recombines the spectrum to the focal region, forming a high-intensity, depth resolved light sheet for laser micromachining, two-photon polymerization and multi-photon imaging. The seminar will be concluded with future research directions.
Biography：
Dr. Shih-Chi Chen received his B.S. degree in Mechanical Engineering from the National Tsing Hua University, Taiwan, in 1999. He received his S.M. and Ph.D. degrees in Mechanical Engineering from the Massachusetts Institute of Technology, Cambridge, in 2003 and 2007, respectively. Following his graduate work, he entered a post-doctoral fellowship in the Wellman Center for Photomedicine, Harvard Medical School, where his research focused on biomedical optics and endomicroscopy. From 2009 to 2011, he was a Senior Scientist at Nano Terra, Inc., a start-up company founded by Prof. George Whitesides at Harvard University, to develop precision instruments for novel nanofabrication processes. Joining since 2011, he is presently an Associate Professor in the Department of Mechanical and Automation Engineering at the Chinese University of Hong Kong. His current research interests include ultrafast laser applications, biomedical optics, precision engineering, and nanomanufacturing. Prof. Chen is a member of the American Society for Precision Engineering (ASPE), American Society of Mechanical Engineers (ASME), SPIE, The Optical Society (OSA), and Institute of Electrical and Electronics Engineers (IEEE). He is the recipient of a 2003 R&D 100 Award for the design of a microscale six-axis nanopositioner. In 2013, he received the Early Career Award from University Grants Committee of Hong Kong.
