1. Department of Physics, Faculty of Natural Science and Mathematics, Diponegoro University, Semarang, Indonesia
2. Research Center for Development of Far-Infrared Region, University of Fukui, Fukui, Japan
3. Department of Physics, Faculty of Education, University of Fukui, Fukui, Japan
4. Fukui Science Education Academy, Fukui, Japan
5. Graduate School of Nuclear Power and Energy Safety and Engineering, University of Fukui, Fukui, Japan