Selective interferometric sensing by the use of coherence synthesis

Area of Science:

• Optoelectronics
• Sensor Technology
• Interferometry

Background:

• Imbalanced fiber-optic interferometric sensors are crucial for various sensing applications.
• Controlling sensor sensitivity is key for multiplexing and selective detection.
• Modifying optical source properties offers a potential avenue for sensitivity control.

Purpose of the Study:

• To demonstrate a technique for actively changing the sensitivity of imbalanced fiber-optic interferometric sensors.
• To utilize this technique for selective monitoring of sensors in a fiber-optic array.
• To explore the relationship between optical source coherence and sensor sensitivity.

Main Methods:

• Modifying the power spectrum and coherence function of the input optical source.
• Synthesizing specific coherence functions to achieve differential sensitivity.
• Implementing the technique on a small fiber-optic ladder array.

Main Results:

• Achieved a sensitivity change of up to 70 dB by altering the optical source's coherence function.
• Successfully demonstrated selective monitoring of single sensors within an array.
• Showcased the ability to create high sensitivity for a target sensor while minimizing sensitivity for others.

Conclusions:

• The demonstrated technique effectively controls fiber-optic sensor sensitivity via optical source modification.
• Selective sensor monitoring in arrays is feasible by synthesizing tailored coherence functions.
• Further research into future designs can overcome current implementation limitations.