Optical Fiber Humidity Sensors: A Review

Humidity measurement is the most important physical parameter, most frequently measured quantities. Humidity sensors are transducers that convert the amount of water (H2O) vapor into a measurable parameter. A large no of sensors based on varieties of technologies are available; each one has its pros and cons. This paper reviews the transduction principles of different state of the art fabricated optical fiber-based humidity sensors. Though high-end technology is preferred to develop such sensors for desired specifications, the challenge remains there to fulfill these specifications. After a rigorous literature review of humidity sensors, it is found that optical fiber-based technology works far better than the rest of the techniques especially for the fabrication of humidity sensors.