Optical fibres and fibre tapers with an array of Bragg gratings

Abstract

The properties of optical fibres with an array of fibre Bragg gratings written directly during the fibre drawing are considered. Such optical fibres offer new possibilities for producing new types of active and passive fibre elements due to the enhanced back-reflected signal of the so-called artificial Rayleigh scattering, and are of interest for modelling physical phenomena associated with the statistics of reflecting centres in optical fibres, such as, e.g., localisation of photons. We studied fibres with an array of Bragg gratings written in photosensitive fibres, ordinary single-mode optical fibre of the SMF-28 type and in fibre with a core doped with erbium ions. To control the spectrum width of the reflected signal, we used chirped phase masks, as well as writing arrays of gratings in tapered optical fibres.

Photosensitive Yb-Doped Germanophosphosilicate Artificial Rayleigh Fibers as a Base of Random Lasers

“…Directly during the fiber drawing process, weakly reflecting FBGs were inscribed in the single-mode fiber core using an experimental setup based on an Optosystems CL-5100 KrF excimer laser generating pulsed UV radiation with a wavelength of 248 nm. The inscribing technique for an array of weakly reflecting FBGs distributed over the fiber length and the setup scheme are described in detail in [14,15]. At a constant fiber drawing speed, the distance between the individual gratings is determined by the laser pulse repetition rate.…”

Scientific Applications of Distributed Acoustic Sensing: State-of-the-Art Review and Perspective

“…The development of fiber drawing technologies has led to the development of using fibers with enhanced scattering points (dots) induced by a femtosecond laser or with reflective centers (weak FBGs) [ 81 , 82 ] ( Figure 6 ). For example, DAS with enhanced scattering dots were used to record the potentially harmful effects on a pipeline of different materials (rubber, plastic, aluminum, and steel pipelines) with an average accuracy of 85% [ 83 ], proving their ability to identify various external impact events as authors used four hammers: soft rubber, hard-plastic, aluminum, and stainless-steel hammer heads.…”

The Sensitivity Improvement Characterization of Distributed Strain Sensors Due to Weak Fiber Bragg Gratings

“…The technology allows creating such structures directly during the extraction of fiber, which makes it convenient and inexpensive [ 28 , 30 ]. The reflection coefficient of such WFBGs can be fractions of a percent or less, while their relative amplitude spread in the array will be no more than 15% [ 55 ]. A scheme of the system based on WFBGs is shown in Figure 5 .…”