Compact polarization transceiver module for fiber optic gyroscopes

This paper reports a transceiver module with a high polarization extinction ratio (PER) for the polarization-maintaining interferometric fiber optic gyroscope (PM-IFOG). This transceiver utilizes a graded-index lens featuring a slanted face coated with a multilayer film, enabling simultaneous collimation and beam splitting. Configurations of the graded-index splitter lens and the corresponding transceiver module are simulated and designed using the ray matrix method and physical optical propagation. The optical loss of the transceiver module is about 3.77 dB, and the PER exceeds 25 dB. The IFOG prototype is implemented by integrating the transceiver module with a PM sensing coil. The bias instability of the IFOG prototype is evaluated to be 0.51^◦/h by Allan variance. This research contributes to the reduction in size, weight, power consumption, and cost of PM-IFOG systems.