The influence of pigtail bending radius of optical devices on the performance of fiber optic gyroscope

Abstract

Some single-mode fiber and its elements are used in low-polarization and polarization-maintaining hybrid path of fiber optic gyroscope. As the development of the miniaturization of interferometric fiber gyroscope, in some cases during the fiber optic gyroscope (FOG) light path assemble, the bending radius of optical device pigtails has to be bend with a small radius because of the compact structure requirement, particularly in single-mode pigtails. In single-mode optical fiber, the transmitted core-guided mode light and whispering gallery mode light will interfere with each other, and present influence on the transmitted light. In the precious investigations, the wavelength is fixed to 1550nm to measure the power loss with different bending radius of single-mode fiber. Thus, in this paper, a three-in-one integrated light source with the wavelength 1310nm is used for the investigation. The effect of single-mode fiber with bending radius from 4mm to 20mm and winding number from 10-50 will be investigated. It shows that single-mode fiber bending can lead to the transmitted light mean wavelength drifting and oscillating as the temperature ramping.