1. Department of Optical Engineering, College of Optical, Mechanical and Electrical Engineering, Zhejiang A&F University, Lin'an 311300, China
2. The State Key Laboratory of Industry Control Technology, College of Control Science and Engineering, Hangzhou 310027, China
3. Radiation Monitoring Technical Center of Ministry of Ecology and Environment, State Environmental Protection Key Laboratory of Radiation Monitoring, Hangzhou 310012, China