The F0G70A single axis fiber optic gyroscope is a fully solid-state high-precision digital closed-loop high-precision single axis fiber optic gyroscope that integrates optics, mechanics, and electronics. Adopting self-developed high-performance photonic crystal polarization maintaining fiber ring, low-temperature resistant coating, and precise fiber untwisting process, not only eliminates the impact of temperature changes and geomagnetism on the performance of the gyroscope to the greatest extent, but also significantly improves key indicators of the fiber optic gyroscope, such as zero bias stability, angle random walk, proportionality factor linearity, and stability.