Miniature interferometric humidity sensor based on an off-center polymer cap onto optical fiber facet

In this work, we propose an interferometric humidity sensor based on a polymer micro-cap bonded off-center on the polished end of a standard single mode fiber (SMF). In our sensor, the sensitive part is the micro-cap. In the interferometer fabrication process, we can adjust the misalignment between...

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Detalles Bibliográficos
Autores: Arrizabalaga Uriarte, Oskar, Velasco Pascual, Javier, Zubia Zaballa, Joseba Andoni, Sáez de Ocáriz, Idurre, Villatoro Bernardo, Agustín Joel
Tipo de recurso: artículo
Fecha de publicación:2019
País:España
Institución:Universidad del País Vasco
Repositorio:Addi. Archivo Digital para la Docencia y la Investigación
OAI Identifier:oai:addi.ehu.eus:10810/37536
Acceso en línea:http://hdl.handle.net/10810/37536
Access Level:acceso abierto
Palabra clave:optical fiber sensors
interferometers
microsensors
polymer cap
humidity sensors
energy-physics applications
fabry-perot-interferometer
bragg grating sensor
relative-humidity
cavity
oxide
film
Descripción
Sumario:In this work, we propose an interferometric humidity sensor based on a polymer micro-cap bonded off-center on the polished end of a standard single mode fiber (SMF). In our sensor, the sensitive part is the micro-cap. In the interferometer fabrication process, we can adjust the misalignment between the core and the micro-cap. It allowed us to control the visibility of the interference pattern. In our device, water molecules absorbed by the polymer microcap causes changes in the height of the microcap. This results in measurable shifts of the interference pattern. The fabricated samples were tested in a calibrated climatic chamber in the range from (similar to)10 to (similar to)95% of relative humidity (RH). The sensitivity and resolution of our device was found to be 148 pm per %RH and 0.04% RH, respectively. The obtained results suggest that our sensors can be useful to monitor relative humidity (RH) in miniature spaces.