Epoxy-Coated Side-Polished Fiber-Optic Temperature Sensor for Cryogenic Conditions

Area of Science:

• Materials Science
• Optical Engineering
• Sensor Technology

Background:

• Cryogenic temperature monitoring requires robust and sensitive sensors.
• Traditional sensors may face limitations in extreme low-temperature environments.
• Optical fiber sensors offer potential for remote and accurate measurements.

Purpose of the Study:

• To develop a novel fiber-optic sensor for cryogenic temperature measurement.
• To enhance the sensitivity and robustness of optical fiber sensors at low temperatures.
• To investigate the thermo-optic effect of epoxy polymer coatings on side-polished optical fibers.

Main Methods:

• Coating side-polished optical fiber (SPF) with an epoxy polymer.
• Utilizing the evanescent field interaction with the polymer coating.
• Measuring transmitted optical intensity variations across a temperature range.
• Analyzing the thermo-optic effect of the polymer layer.

Main Results:

• Achieved a transmitted optical intensity variation of 5 dB.
• Obtained an average temperature sensitivity of -0.024 dB/K.
• Demonstrated enhanced sensor head robustness in a low-temperature environment.
• Validated the effectiveness of the evanescent field-polymer coating interlinkage.

Conclusions:

• The epoxy-coated SPF sensor is suitable for cryogenic temperature measurements.
• The thermo-optic effect significantly improves sensor performance at low temperatures.
• This fiber-optic sensor offers a promising solution for demanding cryogenic applications.