1. State Key Laboratory of Precision Measurement Technology and Instrument; Department of Precision Instrument, Tsinghua University; Beijing 100084 People's Republic of China
2. Department of Precision Instrument; Tsinghua University; Beijing 100084 People's Republic of China
3. Beijing Laboratory for Biomedical Detection Technology and Instrument, Department of Precision Instrument; Tsinghua University; Beijing 100084 People's Republic of China