Engineering Commons^™

Simultaneous Measurement Of Temperature And Pressure With Cascaded Extrinsic Fabry-Perot Interferometer And Intrinsic Fabry-Perot Interferometer Sensors, Yinan Zhang, Jie Huang, Xinwei Lan, Lei Yuan, Hai Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents an approach for simultaneous measurement of temperature and pressure using miniaturized fiber inline sensors. The approach utilizes the cascaded optical fiber inline intrinsic Fabry-Perot interferometer and extrinsic Fabry-Perot interferometer as temperature and pressure sensing elements, respectively. A CO₂ laser was used to create a loss between them to balance their reflection power levels. The multiplexed signals were demodulated using a Fast Fourier transform-based wavelength tracking method. Experimental results showed that the sensing system could measure temperature and pressure unambiguously in a pressure range of 0 to 6.895 x 10⁵ Pa and a temperature range from …

Femtosecond Laser Micro-Machined Optical Fiber Based Embeddable Strain And Temperature Sensors For Structural Monitoring, Armadeep Kaur

Doctoral Dissertations

"Structural monitoring technology is becoming increasingly important for managing all types of structures. Embedding sensors while constructing new structures or repairing the old ones allows for continual monitoring of structural health thus giving an estimate of remaining utility. Along with being embeddable, miniaturized sensors that are easy to handle are highly sought after in the industry where in-situ monitoring is required in a harsh environment (corrosive atmosphere, high temperatures, high pressure etc.).

This dissertation demonstrates the use of femtosecond laser-fabricated Fabry-Perot interferometer (FPI) based optical fiber sensors for embedded applications like structural health monitoring. Two types of Fabry-Perot interferometer sensors, …

Microcavity Strain Sensor For High Temperature Applications, Amardeep Kaur, Steve Eugene Watkins, Jie Huang, Lei Yuan, Hai Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

A microcavity extrinsic Fabry-Perot interferometric (EFPI) fiber-optic sensor is presented for measurement of strain. The EFPI sensor is fabricated by micromachining a cavity on the tip of a standard single-mode fiber with a femtosecond (fs) laser and is then self-enclosed by fusion splicing another piece of single-mode fiber. The fs-laser-based fabrication makes the sensor thermally stable to sustain temperatures as high as 800°C. The sensor exhibits linear performance for a range up to 3700 µε and a low temperature sensitivity of only 0.59 pm/°C through 800°C.