Fiber-diffraction Interferometer using Coherent Fiber Optic Taper

Fiber-diffraction Interferometer using Coherent Fiber Optic Taper

Citation

Kihm, H., & Lee, Y. (2007). Fiber-diffraction Interferometer using Coherent Fiber Optic Taper. Meas. Sci. Technol. This information is found at the very beginning of the provided source document.

Keywords

  • fiber-diffraction interferometer
  • coherent fiber optic taper (FOT)
  • thermally-expanded core (TEC) single-mode fiber (SMF)
  • vibration desensitization
  • fringe stabilization
  • optical testing

Brief

A fiber-diffraction interferometer that uses a coherent fiber optic taper (FOT) to stabilize interference fringes in an uncontrolled environment is presented.

Summary

This article presents a new fiber-diffraction interferometer that uses a coherent fiber optic taper (FOT) to stabilize interference fringes in environments with vibrations.
The interferometer condenses the measurement wave through an FOT and a single-mode fiber with a thermally-expanded core (TEC) to create a reference wave. This design makes the interferometer less sensitive to vibrations because both the reference and measurement waves experience the vibration, stabilizing the interference fringes.
The FOT improves upon previous designs that used only a single-mode fiber. Using only a single-mode fiber can lead to unstable fringes when the test optic vibrates because it's difficult to focus the aberrant measurement wave into the small core of the fiber. However, the FOT's large numerical aperture allows it to capture almost all of the incoming light, making it less sensitive to focus shifts caused by vibrations.
Experimental results demonstrated that the FOT-based interferometer can maintain fringe visibility even when the test surface is tilted, which would significantly reduce fringe visibility in interferometers that use only a single-mode fiber. The article concludes that combining an FOT with a spatial phase shifter could lead to a highly repeatable, vibration-insensitive interferometer.


Origin: https://www.semanticscholar.org/reader/a3d6e1ddd74797a230e3280d8d99d7d634ab9705

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