Vibrating sensing system based on optical excitation and detection using optical fiber

In this paper, we propose a MEMS vibrating sensing system for application to networked sensing systems and discuss simulation results. A MEMS vibrating sensor is excited by optical pulses from an optical fiber connected to a laser diode. The vibration velocity of the sensor is detected by optical Doppler measurement with another laser diode and photodiode. The optical pulse frequency is tuned to the resonant frequency of the MEMS sensor based on the optical Doppler measurement result. The resonant frequency of this vibrating sensor can reflect physical quantities such as temperature, pressure, and gas density. The main features of the sensing system are its ability to be used as an isolated sensor with no electronic circuit or power supply and its ability to sense multiple points by connecting sensors of different resonance frequencies to one optical fiber in parallel.