Fast Response and Low-Noise Optical Pressure Measurements Based on Squeeze-Film Damping Effect

Micro-cantilever device combined with interferometry ranging system, based on optical pressure, can convert the measurement of laser power to micro-displacement. The vibration state of the device directly affects the measurement response time and displacement noise level. The structural parameters of the micro-cantilever device are designed and simulated to ensure the linearity and sensitivity. The glass plate and the micro-cantilever device are used to form a thin air gap, and the vibration characteristics of the cantilever are improved by adjusting the squeeze-film damping, which reduces the measurement response time from 20 s to less than 0.5 s. The vibration characteristics of the micro-cantilever are investigated with different damping coefficient, and the response time is further optimized to 74 ms with an average displacement noise level of 10 nm. The calibration of the elastic coefficient is completed by using standard weights. High-power laser repeatability experiments and single pulse tests are carried out.