Affiliation: | a Department of Electronic Engineering, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515, Japan b School of Instrument Science and Opto-electronic Engineering, Hefei University of Technology, Hefei, Anhui 230009, China c Faculty of Science, King Mongkut's Institute of Technology Ladkrabang, Bangkok 10520, Thailand |