Integrated Optical Chip With Low-Loss Waveguide Coupler for Miniaturized Fiber Optic Gyroscopes

We present an integrated optical chip (IOC) featuring a low-loss and compact waveguide coupler for miniaturized interferometric fiber optic gyroscopes (IFOGs). The IOC integrates a superluminescent diode (SLD), photodiode (PD), integrated coupler chip (ICC), and trans-impedance amplifier (TIA) within a compact 28 mm² footprint, significantly reducing the size, weight, and cost compared to conventional discrete modules. The gyroscope prototype based on this IOC achieves bias stability of 0.039°/h, bias instability of 0.0233°/h, and an angular random walk coefficient of 0.00549°/h¹/² over a 100-second integration time. This integration strategy offers a high-precision, space-saving solution for tactical-grade applications, such as unmanned aerial vehicles and compact navigation systems, representing a significant breakthrough in the integration of fiber optic gyroscopes.