Optical properties of the fiber-optic temperature sensor based on the side-hole fiber filled with indium.

A highly sensitive temperature sensor was made by use of a side-hole glass fiber filled with indium metal, and its optical properties were investigated. The temperature sensitivity of the fiber-optic temperature sensor was dλ/dT=-7.38 nm/K. The temperature sensitivity was also examined in sensors made by different lengths of the side-hole fiber and the indium-filled fiber region. The temperature sensitivity could be varied in the range of -1.83 to -7.38 nm/K by changing the relative length between the side-hole fiber and the indium-filled fiber region.