3D Finite Element Model for Writing Long-Period Fiber Gratings by CO2 Laser Radiation

Sensors

João M. P. Coelho¹  Marta Nespereira¹  Manuel Abreu¹ 

[1] Laboratory of Optics, Lasers and Systems, Faculty of Sciences, University of Lisbon, Campus do Lumiar, Estrada do Paço do Lumiar, 22, Building D, 1649-038 Lisboa, Portugal; E-Mails:

关键词: laser processing;    long-period fiber gratings;    finite element modeling;    fiber-based sensors;    refractive-index modulation;    thermo-mechanical processes;   

DOI  :  10.3390/s130810333

来源: mdpi

【 摘 要 】

In the last years, mid-infrared radiation emitted by CO₂ lasers has become increasing popular as a tool in the development of long-period fiber gratings. However, although the development and characterization of the resulting sensing devices have progressed quickly, further research is still necessary to consolidate functional models, especially regarding the interaction between laser radiation and the fiber's material. In this paper, a 3D finite element model is presented to simulate the interaction between laser radiation and an optical fiber and to determine the resulting refractive index change. Dependence with temperature of the main parameters of the optical fiber materials (with special focus on the absorption of incident laser radiation) is considered, as well as convection and radiation losses. Thermal and residual stress analyses are made for a standard single mode fiber, and experimental results are presented.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.