A novel MOEMS gyroscope based on a two-dimensional photonic crystal array

Abstract Currently, most MEMS (Micro-electromechanical systems) gyroscopes use capacitive detection solution to measure the displacement due to angular velocity for its simplicity. However, this method has many unavoidable errors which will decrease the gyroscopes’ precision, such as parasitic capacitance, electromagnetic interference. Recently, different optical detection structures are introduced into the structure of MEMS gyroscopes due to their great sensitivity and strong anti-interference capabilities, known as MOEMS (Micro-opto-electromechanical systems) gyroscopes. However, different forms of gyroscope structures have different modes of motion, and their integration with optical detection structures still presents significant challenges. In this paper, a x-axis gyroscope with a two-dimensional photonic crystal array optical detection structure is designed. A novel dual-decoupled coupling beams are incorporated and their decoupling ability is analyzed using simulation tools. Besides, a double-layer two-dimensional photonic crystal array is designed and its detection capability and anti-interference level are simulated and analyzed. Simulation results show that the dual-decoupled coupling beams can suppress perturbative forces in non-sensitive directions by 3.9 and 5.7 times, and the two-dimensional photonic crystal array has good in-plane consistency and high cross-coupling error suppression, capable of realizing 32 times coupling error suppression. Finally, the sensitivity of the designed prototype is verified by simulation to reach 21.2377 mV/(°/s). This demonstrates that the designed gyroscope has a large sensitivity while maintaining good anti-interference capability.