Optical fiber sensor for humidity monitoring based on thermal lens detection technique

Abstract

Abstract:An optical fiber humidity sensor based on a thermal lens detection technique is proposed. This sensor allows us to measure humidity without special treatment of the clad of optical fiber in spite of a certain optical absorption path-length under 50 µm. Because of this, we believe that our humidity sensor will have a long lifetime satisfying uses with severe requirements. Our sensor is also extremely small (e.g., 20 mm in length and 5 mm in diameter) and robust. It is also confirmed that our optical fiber humidity sensor can measure absolute humidity. Keywords: optical fiber sensor, humidity sensor, thermal lens, spherical lensed fiber Classification: Photonics devices, circuits, and systems References[1] F. J. McAleaver and B. D. MacCraith, "Diode-pumped thulium-doped zirconium fluoride fibre as a fluorescent source for water sensing," Electron.