Professor Wei Gao received his Bachelor degree in precision instrumentation engineering from Shanghai Jiao Tong University, China in 1986, followed by MS and PhD degrees in precision engineering from Tohoku University, Japan in 1991 and 1994, respectively. He is currently a professor and the director of the Research Center for Precision Nanosystems in the Department of Nanomechanics, Tohoku University. He acted as a visiting professor at the Center for Precision Metrology, University of North Carolina at Charlotte, USA, in 1998. He is an associate editor for Precision Engineering, Journal of the International Society for Precision Engineering and Nanotechnology. He has served as the chair or co-chair of six international conferences and symposiums on measurement held in China, Japan, Hong Kong and the US. He is a member of ASPE, JSPE, JSME and CIRP. Professor Wei Gao has been working on precision engineering and metrology for about twenty years. He and his group have developed a number of optical sensors and scanning measuring systems for dimensional measurement and precision motion control. Recently, Wei Gao has been focusing his research on a new field of metrology called precision nanometrology, which aims to realize nanometric accuracy in dimensional measurement over a broad measurement range from micrometers to meters. Professor Wei Gao is the author or co-author of more than 200 scientific articles. He is the chapter author of six books, including two published by Springer. He is the inventor or co-inventor of 45 patents. He has received more than ten academic awards, including the JSPS Award and the JSPS Numada Paper Award from the Japan Society for Precision Engineering, the Award for Young Scientist from the Japan Society of Mechanical Engineers, and the Contribution Award from the International Journal of Precision Engineering and Manufacturing. He has been invited to provide keynote speeches at a number of international conferences and symposiums on measurement.