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

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, optical detection structures with higher detection sensitivity and immunity to interference have been introduced into MEMS gyroscopes, which are known as MOEMS (Micro-Opto-Electro-Mechanical 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 y-axis gyroscope with a two-dimensional photonic crystal array optical detection structure is designed. A novel dual-decoupled beam is designed and its decoupling ability is analyzed using simulation tools. Besides, a double-layer two-dimensional photonic crystal array is designed, 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 x and z axis by 3.9 and 5.5 times, separately. 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 gyroscope is verified by simulation to reach 21.2377 mV/(°/s), which demonstrates that the designed gyroscope has a large sensitivity while maintaining good anti-interference capability.