Highly Sensitive Temperature Sensing Performance of a Microfiber Fabry-Perot Interferometer with Sealed Micro-Spherical Reflector

Abstract

A temperature probe has been proposed by inserting a microfiber taper into a silica hollow core fiber with a microsphere end. The sealed air cavity in the microsphere and the inserted microfiber acted as the two reflectors of a Fabry-Perot interferometer, respectively. The contribution of both microfiber diameter and cavity length on the interference spectra was analyzed and discussed in detail. The temperature change was experimentally determined by monitoring the wavelength location of the special resonance dip. By filling the air cavity with poly-dimethylsiloxane (PDMS), a high temperature sensitivity of 3.90 nm/°C was experimentally demonstrated. This temperature probe with the diameter of 150 μm and length of 10 mm will be a promising candidate for exploring the miniature or implantable sensors.

Study of the Vernier Effect Based on the Fabry–Perot Interferometer: Methodology and Application

“…Among them, compared to the sensor proposed in [4,8,38], the sensor we proposed has higher sensitivity and occupies a smaller bandwidth. The measurement range of the proposed sensor is smaller than the sensor proposed in [4,38,39], but we can change the design parameters to expand the measurement range, and this is at the expense of sensitivity. To further improve the sensitivity of the Vernier effect, a light source with a larger bandwidth and a higher resolution device are required.…”

An In-Line Fiber Optic Fabry–Perot Sensor for High-Temperature Vibration Measurement

“…The fiber optic vibration sensors are mainly based on fiber Bragg gratings (FBGs), Mach-Zehnder interferometers, or Fabry-Perot (FP) interferometers. Of these, the FP interferometer can be easily formed in small structures, and it has the advantages of stability and is easy to be demodulated [12][13][14][15][16]. Meanwhile, among the fiber optic vibration sensors, the in-line fiber optic vibration sensor is particularly small, can be embedded in the structure for detection, and has the prospect of multi-point distributed measurement and combination with other types of sensors.…”