scholarly journals Novel Fabrication Technique of Superimposed LPG with Different Grating Pitches for the Simultaneous Detection of Refractive Index and Temperature

Proceedings ◽  
2019 ◽  
Vol 15 (1) ◽  
pp. 35
Author(s):  
Trono ◽  
Valeri ◽  
Baldini
Keyword(s):  
Refractive Index ◽  
Optical Fiber ◽  
Simultaneous Detection ◽  
Optical Fiber Sensors ◽  
Fabrication Technique ◽  
Environmental Chemical ◽  
Fiber Sensors ◽  
Long Period ◽  
Biochemical Sensing ◽  
Long Period Gratings

Optical fiber sensors based on in-fiber Long Period Gratings (LPG) have attracted considerableinterest in the context of environmental, chemical and biochemical sensing. [...]

Fabrication of Optical Fiber Sensors Based on Femtosecond Laser Micro Machining

2020 ◽  
Vol 8 (4) ◽  
Author(s):  
Fengfeng Zhou ◽  
Seunghwan Jo ◽  
Xingyu Fu ◽  
Jung-Ting Tsai ◽  
Martin Byung-Guk Jun
Keyword(s):  
Refractive Index ◽  
Femtosecond Laser ◽  
Optical Fiber ◽  
Refractive Index Change ◽  
Optical Fiber Sensors ◽  
Objective Lens ◽  
Machining Parameters ◽  
Fiber Sensors ◽  
The Core ◽  
First Time

Abstract In this research, we proposed fabrication process of optical fiber sensors using femtosecond laser and their applications. A beam of femtosecond laser was focused by an objective lens in the optical fiber. By testing different conditions, a group of machining parameters was found that achieve a minimum machining resolution of 3.2 μm. To ablate the core of the optical fiber, which is buried deep inside the cladding, precisely, part of the cladding was removed to expose the core as close as possible to the air. By making a complex pattern to modify the optical path of the laser inside an optical fiber, a sensitivity of 942.8–1015.6 nm per refractive index unit (nm/RIU) was obtained for liquid refractive index sensing. For another sensor, a sensitivity of 1.38 × 105 nm/RIU was obtained, which is high enough to detect small amount of refractive index change of air. It is known to be the first time that we fabricated a complex microstructure in an optical fiber to modify the propagation of the light using femtosecond laser. This research shows the possibility of a complex modification of light in an optical fiber using laser machining.

scholarly journals Optical Fiber Interferometers Based on Arc-Induced Long Period Gratings at INESC TEC

Sensors ◽  
2021 ◽  
Vol 21 (21) ◽  
pp. 7400
Author(s):  
Paulo Caldas ◽  
Gaspar Rego
Keyword(s):  
Refractive Index ◽  
Optical Fiber ◽  
Cavity Length ◽  
Fiber Optic ◽  
Fiber Diameter ◽  
Long Period Grating ◽  
Long Period ◽  
Long Period Gratings ◽  
Cladding Mode ◽  
Mode A

In this work, we review the most important achievements of an INESC TEC long-period-grating-based fiber optic Michelson and Mach–Zehnder configuration modal interferometer with coherence addressing and heterodyne interrogation as a sensing structure for measuring environmental refractive index and temperature. The theory for Long Period Grating (LPG) interferometers and coherence addressing and heterodyne interrogation is presented. To increase the sensitivity to external refractive index and temperature, several LPG interferometers parameters are studied, including order of cladding mode, a reduction of the fiber diameter, different type of fiber, cavity length and the antisymmetric nature of cladding modes.

scholarly journals Review on Optical Fiber Sensors Based on the Refractive Index Tunability of Ferrofluid

2017 ◽  
Vol 35 (16) ◽  
pp. 3406-3412 ◽  
Author(s):  
Yong Zhao ◽  
Xu Liu ◽  
Ri-Qing Lv ◽  
Ya-Nan Zhang ◽  
Qi Wang
Keyword(s):  
Refractive Index ◽  
Optical Fiber ◽  
Optical Fiber Sensors ◽  
Fiber Sensors

Advances in two-mode optical fiber sensors incorporating photoinduced refractive index gratings

1993 ◽  
Author(s):  
Mark S. Miller ◽  
Jonathan A. Greene ◽  
Suzanne E. Starr ◽  
Anbo Wang ◽  
Kent A. Murphy ◽  
...  
Keyword(s):  
Refractive Index ◽  
Optical Fiber ◽  
Optical Fiber Sensors ◽  
Fiber Sensors
Sign in / Sign up

Export Citation Format

Share Document