Structural design and simulation of a MOEMS gyroscope based on subwavelength grating detection

Area of Science:

• Optics and Photonics
• Microelectromechanical Systems (MEMS)
• Inertial Sensing

Background:

• Traditional gyroscopes face limitations in sensitivity and size.
• Microelectromechanical system (MEMS) gyroscopes offer miniaturization advantages.
• Wood's anomaly in subwavelength gratings presents a novel optical sensing mechanism.

Purpose of the Study:

• To propose and simulate a novel out-of-plane microelectromechanical system (MOEMS) gyroscope.
• To leverage Wood's type anomaly in a subwavelength grating pair for enhanced Coriolis force detection.
• To establish a theoretical foundation for subwavelength grating-based MOEMS gyroscope design.

Main Methods:

• Development of a simulation model for the MOEMS gyroscope.
• Utilizing Wood's anomaly for optical diffraction amplitude modulation based on grating displacement.
• Optimization of subwavelength grating parameters and tolerance analysis.
• Implementation of the gyroscope system model in Simulink for performance evaluation.

Main Results:

• The proposed structure demonstrates good modal matching and a structural sensitivity of 0.094 nm/°/s.
• Optimal grating parameters yielded an optical diffraction sensitivity of 10.4%/nm.
• Simulations show a total gyroscope sensitivity of 3.04 mV/°/s and a noise floor of 5.1×10^-5 °/s/√Hz.

Conclusions:

• The subwavelength grating-based MOEMS gyroscope effectively utilizes Wood's anomaly for sensitive inertial measurement.
• The design offers a promising theoretical basis for fabricating high-performance MOEMS gyroscopes.
• This approach provides a novel pathway for advancing optical MEMS inertial sensors.