Multi-point fiber refractometer using Fresnel reflection and a coherent optical frequency-domain multiplexing...

Area of Science:

• Optoelectronics
• Fiber Optics Sensing

Background:

• Refractive index sensing is crucial for various applications.
• Existing methods can be complex or costly.

Purpose of the Study:

• To demonstrate a simple and cost-effective multi-point refractometer.
• To achieve high refractive index resolution using basic components.

Main Methods:

• Utilized coherent optical frequency-domain multiplexing (OFDM).
• Employed interferometers of varying lengths as local refractive index sensors.
• Fabricated reference reflectors by splicing hollow optical fiber into standard single-mode fiber (SMF-28).

Main Results:

• Successfully demonstrated a multi-point refractometer with a simple configuration.
• Achieved a refractive index resolution of 6x10^-4.
• Proof-of-concept experiments validated the sensor's performance.

Conclusions:

• The developed refractometer offers a simple and manufacturable solution for refractive index sensing.
• Coherent optical OFDM is effective for multi-point sensing applications.
• The sensor shows potential for various applications requiring precise refractive index measurements.