Tsun-Hsu Chang received the B.S. degree in physics from National Central University, Taoyuan, Taiwan, in 1991 and the Ph.D. degree in physics from National Tsing Hua University (NTHU), Hsinchu, Taiwan, in 1999. He joined NTHU in 2003 as an Assistant Professor, and in 2011 he became a Full Professor. He served as the Vice-Chair of Physics Department for seven years and the Chair of Interdisciplinary Program of Science for two years. He also served as the Director of Physics Research Promotion Center as well as the Director of Tsing Hua Optoelectronics Research Interdisciplinary Center at different times. He is currently the Chairman of the Physics Department as well as the Director of Institute of Astronomy. Professor Chang’s research interests can be divided into three main themes: (1) Frequency-tunable, high-power terahertz gyrotrons, (2) Microwave/material interaction and characterization, and (3) Microwave physics and applications. His group can measure the complex permittivity and permeability from sub GHz up to 1 THz for the samples in solid, liquid, powder, or fiber.