Fast and stable gratings inscription in POFs made of different materials with pulsed 248 nm KrF laser.

C A F Marques,B Ortega,H K Rasmussen,G Woyessa,A Leal Junior,O Bang,P Antunes,R Min,K Nielsen,A Fasano

doi:10.1364/oe.26.002013

Abstract

This paper presents fiber Bragg grating (FBG) inscription with a pulsed 248 nm UV KrF laser in polymer optical fibers (POFs) made of different polymers, namely polymethyl methacrylate (PMMA), cyclic-olefin polymer and co-polymer, and Polycarbonate. The inscribed gratings and the corresponding inscription parameters are compared with grating inscribed in POFs made of the aforementioned materials but with the hitherto most used laser for inscription, which is a continuous wave 325 nm UV HeCd laser. Results show a reduction of the inscription time of at least 16 times. The maximum time reduction is more than 130 times. In addition, a reflectivity and a bandwidth close to or higher than the ones with the 325 nm laser were obtained. The polymer optical fiber Bragg gratings (POFBGs) inscribed with the 248 nm laser setup present high stability with small variations in their central wavelength, bandwidth, and reflectivity after 40 days.

Highlights

Optical fiber sensors are compact, lightweight, allow multiplexing systems, present electromagnetic immunity and electrical isolation [1]
This paper presents fiber Bragg grating (FBG) inscription with a pulsed 248 nm UV KrF laser in polymer optical fibers (POFs) made of different polymers, namely polymethyl methacrylate (PMMA), cyclic-olefin polymer and co-polymer, and Polycarbonate
Optical fiber sensors are commonly made of silica fibers, advances in polymer processing [2], characterization [3] and fiber Bragg grating (FBG) inscription [4] enable the application of polymer optical fibers (POFs) in sensing applications

Summary

Introduction

Optical fiber sensors are compact, lightweight, allow multiplexing systems, present electromagnetic immunity and electrical isolation [1]. POFs present additional advantages when compared with their silica counterparts, which include flexibility in bending, higher fracture toughness, and lower Young Modulus that provides higher sensitivity in strain sensing applications [5]. The biocompatibility and non-brittle nature of POFs means that they are clinically acceptable and can be employed in in-vivo applications [6]. Such advantages of POF sensors enable their application to measure parameters like temperature [7], strain [8], humidity [9], curvature [10], acceleration [11], and liquid level [12]. POF sensors are employed in biomedical applications such as antibody [13,14] and glucose sensors [15]

Methods

Results

Conclusion