This Tutorial Text delivers essential information concerning fiber Bragg gratings to professionals and researchers with an approach based on rules of thumb and practical aspects, enabling quick access to the main principles and techniques, and allowing readers to set up their own laboratory or application. It provides detailed information about how to operate and use these novel sensors, particularly with respect to the required infrastructure, daily operation, and possible applications. After a discussion of the primary concepts, practical aspects regarding the development of a FBG laboratory and how these components are manufactured and used in practical applications are presented. The following chapters outline the operation of Bragg gratings and, for instance, discuss how measurement information can be retrieved (interrogation techniques), calibration methods, and how to prepare and deploy the devices in real monitoring conditions. The final chapters present several successful, real-world applications of the technology.
This work presents an innovative automated Fiber Bragg Grating (FBG) based tunable optical filter (TOF) controlled by temperature to be used in temperature compensating schemes in FBG sensing set-ups. Mechanical and electronic aspects are discussed, and the implemented FBG-TOF viability and reliability in sensing systems are showed. The system was employed to demodulate a high voltage AC signal applied to a FBG-PZT sensor, showing good linearity and sensitivity.
The authors present the development of a opto-magnetostrictive current monitoring device intended to be used in situations where high voltages are involved. The system offers not only measurement reliability, but to be also practical and light weighted. Fiber Bragg gratings (FBG) are employed in the measurement procedure: the current is acquired using a hybrid sensor head set-up, that is, an FBG together with a magnetostrictive rod.