Sequential Dual Coating with Thermosensitive Polymers for Advanced Fiber Optic Temperature Sensors

Area of Science:

• Optoelectronics
• Materials Science
• Sensor Technology

Background:

• Fabry-Perrot interferometers (FPIs) are optical sensors sensitive to environmental changes.
• Developing highly sensitive temperature sensors is crucial for various scientific and industrial applications.
• Dual polymer coatings offer potential for enhanced sensor performance through synergistic effects.

Purpose of the Study:

• To systematically design and fabricate dual polymer Fabry-Perrot interferometer (DPFPI) sensors for highly sensitive temperature detection.
• To investigate the impact of polymer sequence, concentration, and optical path length on sensor sensitivity.
• To evaluate the performance, repeatability, reliability, and precision of the developed DPFPI temperature sensors.

Main Methods:

• Systematic design and fabrication of four different dual polymer FPI sensors using poly(methyl methacrylate) (PMMA) and polycarbonate (PC).
• Utilizing the Vernier effect by altering polymer sequence and coating solution concentration to modify optical path lengths.
• Experimental characterization of temperature sensitivity for each fabricated DPFPI sensor.

Main Results:

• The PC_PMMA_S1 DPFPI sensor achieved a maximum temperature sensitivity of 1238.7 pm/°C.
• This sensitivity was approximately 4.4-fold higher than PMMA-coated sensors and 1.4-fold higher than PMMA_PC_S1-coated sensors.
• The results indicated that coating sequence and dual polymer layer properties significantly influence sensor sensitivity.

Conclusions:

• The PC_PMMA_S1 DPFPI sensor demonstrates high efficacy, repeatability, reliability, and precision for temperature readings.
• The synergistic optical properties of the dual polymer layers, particularly the PMMA outer layer, contribute to enhanced sensitivity.
• The study validates the feasibility of using dual polymer coatings in DPFPI sensors for advanced temperature sensing applications.