Insights and Aspects to the Modeling of the Molten Core Method for Optical Fiber Fabrication

The molten core method (MCM) is a versatile technique to fabricate a wide variety of optical fiber core compositions ranging from novel glasses to crystalline semiconductors. One common feature of the MCM is an interaction between the molten core and softened glass cladding during the draw process, which often leads to compositional modification between the original preform and the drawn fiber. This causes the final fiber core diameter, core composition, and associated refractive index profile to vary over time and longitudinally along the fiber. Though not always detrimental to performance, these variations must, nonetheless, be anticipated and controlled as they directly impact fiber properties (e.g., numerical aperture, effective area). As an exemplar to better understand the underlying mechanisms, a silica-cladding, YAG-derived yttrium aluminosilicate glass optical fiber was fabricated and its properties (core diameter, silica concentration profile) were monitored as a function of draw time/length. It was found that diffusion-controlled dissolution of silica into the molten core agreed well with the observations. Following this, a set of first order kinetics equations and diffusion equation using Fick’s second law was employed as an initial effort to model the evolution of fiber core diameter and compositional profile with time. From these trends, further insights into other compositional systems and control schemes are provided.

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Strain and Curvature Stability Enhanced SMF Introduction

Advanced Electromagnetics ◽

10.7716/aem.v6i1.431 ◽

2017 ◽

Vol 6 (1) ◽

pp. 63

Author(s):

S. Makouei

Keyword(s):

Refractive Index ◽

Optical Fiber ◽

Design Method ◽

Single Mode ◽

Effective Area ◽

Refractive Index Profile ◽

Curvature Radius ◽

Geometrical Parameters ◽

Small Curvature ◽

Bending Loss

In this paper, the strain insensitive single mode optical fiber with low nonlinear effects and ultra low bending loss (BL), appropriate for small curvature radius installation, is presented. The suggested design method is based on the reverse engineering which evaluates the refractive index profile considering proper mode field diameter (MFD) value. Then, so as to attain the desired bending loss and strain response for the optical fiber, the optimization tool of the evolutionary genetic algorithm (GA) is employed to determine the optical and geometrical parameters of the structure. In the first designed fiber, the calculations for BL, MFD, effective area (Aeff), and effective refractive index (neff) sensitivity to strain in the well-known wavelength of 1.55 µm are 0.0018 dB per each turn of 5 mm curvature radius, 8.53 µm, 58 µm2, and 4.5 × 10-8 µɛ-1, respectively. Furthermore, the effect of placing raised outer cladding in the fiber structure is investigated which exhibits the MFD of 8.63 µm, 0.0093 dB BL for single turn of 5 mm radius, and 87 µm2 Aeff at 1.55 µm. In this case the strain sensitivity of 6.7 × 10-8 µɛ-1 is calculated for the neff. The mentioned effective area is magnificently large in the domain of bend insensitive fibers. In the meantime, the designed structures are insensitive to strain which is a crucial feature in applications with small curvature radius.

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Application of Optical Fiber Made of Various Materials with Composite Properties of Materials in Laser Medical Treatment

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.600.222 ◽

2012 ◽

Vol 600 ◽

pp. 222-225

Author(s):

Zhen Zhang ◽

Fang Liu

Keyword(s):

Optical Fiber ◽

Medical Treatment ◽

Plastic Material ◽

Numerical Aperture ◽

Fiber Material ◽

Spot Size ◽

Light Transmittance ◽

Core Diameter ◽

Transmission Distance ◽

Fiber Manufacturing

Though introducing the optical fiber in a laser medical treatment made of different materials, contrast expounded integrated characteristic of the different materials in manufacturing an optical fiber material, summed four aspects need to be considered in the choice of the optical fiber manufacturing material. First, the laser parameters, such as maximum laser power, the wavelength, the transmission distance, the laser beam spot size and numerical aperture of the laser light source. Second, according to the optical fiber light transmittance curve, to identify the optimum transmittance of the application wavelength. Third, determining transmission optical slender core diameter, typically a core diameter is greater than the laser spot size of 2/3; decision sets of plastic material finally.

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Study of the optical parameters of a silica-polymeric optical fiber with a reflective coating made of a thermoplastic fluoropolymer

Industrial laboratory Diagnostics of materials ◽

10.26896/1028-6861-2020-86-7-27-32 ◽

2020 ◽

Vol 86 (7) ◽

pp. 27-32

Author(s):

A. A. Zamyatin ◽

A. A. Makovetskii ◽

I. P. Shilov ◽

D. V. Lapshin

Keyword(s):

Laser Radiation ◽

Optical Fiber ◽

Numerical Aperture ◽

Optical Loss ◽

Fiber Surface ◽

Optical Parameters ◽

Core Diameter ◽

Protective Function ◽

Reflective Coating ◽

Rough Turning

Silica optical fibers (OF) having a core diameter of 400 – 800 μm made of biocompatible materials are widely used in laser medicine. The results of studying the optical parameters of novel silica-polymeric optical fiber with a reflective thermoplastic copolymer coating (tetrafluoroethylene – ethylene) and the influence of coating conditions on these optical parameters are presented. Coatings from polymer melt were applied to the silica fiber surface by orifice drawing. The numerical aperture of the drawn OF was measured by distribution of the laser radiation emerging from OF in the far field. The optical losses were determined by the distribution of the radiation scattered by the reflective coating along the OF length. The scattering parameters of the laser radiation transmitted through OF were estimated by the intensity and indicatrix of scattering. We studied OF samples up to 50 m in length with a silica core of about 400 μm in diameter and reflective coating with a thickness of 70 – 90 μm, the reflective coating also performed a protective function. The quality of applied coating and optical parameters of the OF samples depended on the speed of fiber drawing (coating speed) Vd. A smooth coating was obtained at Vd ≤ 2 m/min. When Vd > 2 m/min the coating became rough, turning into the so-called «shark skin» at Vd = 6 m/min. Observed scattering of radiation passing through the studied OF samples was attributed to the polymer structure which contained both crystalline and amorphous phases with different values of the refractive index. The smallest scattering was observed in a smooth-coated OF. The total optical loss at a wavelength λ = 532 nm amounted to 300 – 720 dB/km (a nominal numerical aperture was 0.44). Short (1.5 – 3 m) OF samples were shown to provide a transmission of 80 – 93% of the input power.

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Optical Fiber Biomedical Sensor Based on Surface Plasmon Resonance

Iraqi Journal of Science ◽

10.24996/ijs.2020.61.7.13 ◽

2020 ◽

pp. 1650-1656

Author(s):

Namaa Salem Rahim ◽

Sudad S. Ahmed ◽

Murtadha Faaiz Sultan

Keyword(s):

Surface Plasmon Resonance ◽

Optical Fiber ◽

Surface Plasmon ◽

Plasmon Resonance ◽

Figure Of Merit ◽

Work Performance ◽

Signal To Noise Ratio ◽

Numerical Aperture ◽

Core Diameter ◽

Biomedical Sensor

Optical fiber biomedical sensor based on surface plasmon resonance for measuring and sensing the concentration and the refractive index of sugar in blood serum is designed and implemented during this work. Performance properties such as signal to noise ratio (SNR), sensitivity, resolution and the figure of merit were evaluated for the fabricated sensor. It was found that the sensitivity of the optical fiber-based SPR sensor with 40 nm thick and 10 mm long Au metal film of the exposed sensing region is 7.5µm/RIU, SNR is 0.697, figure of merit is 87.2 and resolution is 0.00026. The sort of optical fiber utilized in this work is plastic optical fiber with a core diameter of 980 µm, a cladding of 20μm, and a numerical aperture of 0.51.

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optical fiber core diameter

Computer Science and Communications Dictionary ◽

10.1007/1-4020-0613-6_13002 ◽

2000 ◽

pp. 1168-1168

Author(s):

Martin H. Weik

Keyword(s):

Optical Fiber ◽

Core Diameter ◽

Fiber Core

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Research of potentiality of nonlinear effects mitigation by considerable increasing of optical fiber core diameter

10.1117/12.2181085 ◽

2015 ◽

Cited By ~ 3

Author(s):

Vladimir A. Andreev ◽

Vladimir A. Burdin ◽

Anton V. Bourdine ◽

Michael V. Dashkov ◽

Kirill A. Volkov

Keyword(s):

Optical Fiber ◽

Nonlinear Effects ◽

Core Diameter ◽

Fiber Core

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Surface Plasmon Plastic Optical Fiber Resonance with Multi-Layer as Chemical Sensor

Iraqi Journal of Physics (IJP) ◽

10.30723/ijp.v19i50.588 ◽

2021 ◽

Vol 19 (50) ◽

pp. 51-59

Author(s):

Emad Khatar ◽

Sudad Salman Bassam

Keyword(s):

Optical Fiber ◽

Surface Plasmon ◽

Figure Of Merit ◽

Chemical Sensor ◽

Signal To Noise Ratio ◽

Optical Fiber Sensor ◽

Numerical Aperture ◽

Plastic Optical Fiber ◽

Core Diameter ◽

Chemical Materials

A chemical optical fiber sensor based on surface plasmon resonance (SPR) was developed and implemented using multimode plastic optical fiber. The sensor is used to detect and measure the refractive index and concentration of various chemical materials (Urea, Ammonia, Formaldehyde and Sulfuric acid) as well as to evaluate the performance parameters such as sensitivity, signal to noise ratio, resolution and figure of merit. It was noticed that the value of the sensitivity of the optical fiber-based SPR sensor, with 60nm and 10 mm long, Aluminum(Al) and Gold (Au) metals film exposed sensing region, was 4.4 μm, while the SNR was 0.20, figure of merit was 20 and resolution 0.00045. In this work a multimode plastic optical fiber with a core diameter of 980 μm, fluorinated polymer cladding of 20 μm and a numerical aperture of 0.51 was used.

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A Comprehensive Study of Large Negative Dispersion and Highly Nonlinear Perforated Core PCF: Theoretical Insight

10.21203/rs.3.rs-227813/v1 ◽

2021 ◽

Author(s):

Anurag Upadhyay ◽

Shivam Singh ◽

Divya Sharma ◽

Sofyan A Taya

Keyword(s):

Dispersion Compensation ◽

Chromatic Dispersion ◽

Nonlinear Coefficient ◽

Numerical Aperture ◽

Effective Area ◽

Propagation Loss ◽

Optical Parameters ◽

Fiber Core ◽

Negative Dispersion ◽

Highly Nonlinear

Abstract This manuscript deals with a novel photonic crystal fiber (PCF) in which PCF's cladding region bears the air holes of square shape organized in a circular manner. The fiber core is perforated with four circular air-filled holes to instate high nonlinearity and large negative dispersion. The numerical analysis of the designed model is supported by the finite element method (FEM) based COMSOL Multiphysics tool. The optical properties of the propounded PCF like nonlinearity, dispersion, effective area and propagation loss have been observed by altering its geometrical dimensions, especially the diameter of four air holes introduced in the fiber core. Simulation outcome verifies a very high nonlinear coefficient value of 300 W− 1 Km− 1 which is the highest ever achieved value without using any nonlinear materials or liquids in the author's best knowledge. In parallel, the chromatic dispersion is also found negative and reached to the maximum value of -1689 ps/nm/km. Besides, the other essential optical parameters such as birefringence, numerical aperture, and propagation loss were also measured as 2.40×10− 3, 0.59, and 4.12×10− 11 dB/m along with an extremely high core power fraction of 99.98%. Hence, the propounded PCF is suitable for residual dispersion compensation, supercontinuum generation, solitons generation, polarization sustaining devices as well for high bitrate transmission.

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Fabrication of a Chemical Sensor Based on Surface Plasmon Resonance via Plastic Optical Fiber

Iraqi Journal of Science ◽

10.24996/ijs.2020.61.4.8 ◽

2020 ◽

pp. 765-771

Author(s):

Ghufran Mohammed Jassam ◽

Soudad S. Al–Bassam ◽

Murtadha F. Sultan

Keyword(s):

Surface Plasmon Resonance ◽

Optical Fiber ◽

Surface Plasmon ◽

Plasmon Resonance ◽

Figure Of Merit ◽

Chemical Sensor ◽

Optical Fiber Sensor ◽

Numerical Aperture ◽

Plastic Optical Fiber ◽

Core Diameter

In this work, a chemical optical fiber sensor based on Surface Plasmon Resonance (SPR) was designed and implemented using plastic optical fiber. The sensor is used for estimating refractive indices and concentrations of various chemical materials (methanol, distilled water, ethanol, kerosene) as well as for evaluating the performance parameters such as sensitivity, signal to noise ratio, resolution and the figure of merit of the fabricated sensor. It was found that the value of the sensitivity of the optical fiber-based SPR sensor, with 40 nm thick and 10 mm long Au metal film of exposed sensing region, was 3μm/RIU, while the SNR was 0.24, the figure of merit was 20, and the resolution was 0.00066. The sort of optical fiber utilized in this work is plastic optical fiber with a core diameter of 980 μm, a fluorinated polymer cladding of 20μm and a numerical aperture of 0.51.

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