1. College of Mechanical and Electrical Engineering, China Jiliang University, Hangzhou, Zhejiang 310018, China
2. National Institute of Metrology, Beijing 100029, China
3. The Key Laboratory for the Electrical Quantum Standard of State Administration for Market Regulation, Beijing 100029, China
Abstract：A filament-surface capacitive sensor based on self-damping vertical reference to measure the residual horizontal displacement precisely during the vertical movement is presented. The filament electrode works as a direct vertical reference, which avoids the system error caused by indirect-reference conversion. And the liquid damper in the end of the filament electrode ensures the stability of the capacitive sensor. Experiments show that in the range of 0.38~0.4pF, the resolution of the filament-surface capacitive sensor is better than 0.05μm, and the short-term stability is approximately 0.1μm.
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2019, Vol. 40 
