Fiber Optic Field Research Articles

Novel synthesis and spectroscopic analysis of gallium oxide doped zinc phosphate glass

Phosphate glasses are known for their wide applications in the field of optical fiber, lasers, seals and sensors. Glass system containing (40-x) ZnO-xGa2O3-50P2O5- Na2O, where x=0 to 10mol % were prepared. The effect of gallium oxide on the properties of these glasses were studied. To observe the structure of prepared phosphate glasses FTIR was used under the wavelength range of 400-4000 cm-1 . The prominent peaks appeared in region 400 cm-1 to 2500 cm-1 . The glasses were transparent up to 1500 cm-1 which make them suitable in the field of lasers. The FTIR also confirmed that Q2 structure dominates these glasses

Dynamics of M-truncated optical solitons and other solutions to the fractional Kudryashov’s equation

The study of soliton theory plays a crucial role in the telecommunication industry’s utilization of nonlinear optics. The principal area of research in the field of optical solitons revolves around optical fibers, metamaterials, metasurfaces, magneto-optic waveguides, and other related technologies. Therefore, the examination of these solitons received significant attention from scholars in recent years. Optical solitons refer to electromagnetic waves that are confined within nonlinear dispersive medium, wherein the balance between dispersion and nonlinearity effects enables the intensity to remain constant. In this manuscript, the dynamical behavior of Kudryashov’s equation is discussed with the assistance of truncated M-fractional derivative. Kudryashov’s equation is a mathematical model utilized to characterize complex phenomena in telecommunications and transmission technology. It describes the propagation of nonlinear pulses in optical fibers. Different forms of soliton solutions like bright, dark, singular and combo solitions have been extracted. Moreover, hyperbolic, periodic and Jacobi elliptic function solutions are recovered. Two recently modern integration tools like Φ6-expansion method and modified generalized exponential rational function method have been adopted to recover the solutions. The used methods not only provides previously extracted solutions but also secures new solutions. In order to visually depict the output, a variety of graphs featuring distinct shapes are produced in response to appropriate parameter values. The results obtained from this research indicate that the chosen methodologies are effective in improving the understanding of nonlinear dynamical phenomena. A large number of engineers who employ engineering models are expected to find this research interesting. The results demonstrate that the selected methods are practical, straightforward to implement, and applicable to intricate systems across numerous domains, with a specific emphasis on the field of optical fibers. The findings indicate that the system may contain a considerable number of soliton structures.

Telecoms expert disconnects from the network

Having spent more than 40 years working in optical communications, Michael Robertson is one of the world’s longest-serving experts in the field of fibre-optics. To mark his retirement, he talks to Anita Chandran about cross-disciplinary research, the breakthroughs he made and the good and bad sides of fibre optics in the UK.

Optical Fiber Based Temperature Sensors: A Review

The current generation is witnessing a huge interest in optical waveguides due to their salient features: they are of low cost, immune to electromagnetic interference, easy to multiplex, have a compact size, etc. These features of optical fibers make them a useful tool for various sensing applications including in medicine, automotives, biotechnology, food quality control, aerospace, physical and chemical monitoring. Among all the reported applications, optical waveguides have been widely exploited to measure the physical and chemical variations in the surrounding environment. Optical fiber-based temperature sensors have played a crucial role in this decade to detect high fever and tackle COVID-19-like pandemics. Recognizing the major developments in the field of optical fibers, this article provides recent progress in temperature sensors utilizing several sensing configurations including conventional fiber, photonic crystal fiber, and Bragg grating fibers. Additionally, this article also highlights the advantages, limitations, and future possibilities in this area.

Diverse optical solitons to nonlinear perturbed Schrödinger equation with quadratic-cubic nonlinearity via two efficient approaches

In this study, the nonlinear perturbed Schrödinger equation(NPSE) with nonlinear terms as quadratic-cubic law nonlinearity media with the beta derivative is investigated and this investigated model is considered an icon in the field of optical fibers where it describes the wave function or state function of the optical system. Numerous solutions are extracted by engaging two novel schemes known as generalized -expansion method (GEEM) and rational extended sinh-Gordon equation expansion method (REShGEEM) in distinct forms such as bright, dark, singular and combinations of these solutions. In addition, plane wave, periodic and exponential solutions are also recovered. Using the computer application Wolfram Mathematica 11, the dynamic structure and physical characterization of some observed solutions are vividly depicted by sketching different plots. Comparing our new results with well-known literature is also given which justifies the novelty of this work. Obtained results will hold a significant place in the field of nonlinear optical fibers and suggest that the proposed methods are very influential and effective tools for solving more complex nonlinear partial differential equations in mathematical physics, engineering and nonlinear optics.

Single-polarization single-mode hollow-core negative curvature fiber with nested U-type cladding elements

Hollow-core negative curvature fibers (HC-NCFs) have become one of the research hotspots in the field of optical fiber because of their potential applications in the data and energy transmissions. In this work, a new kind of single-polarization single-mode HC-NCF with nested U-type cladding elements is proposed. To achieve the single-polarization single-mode transmission, we use two different silica tubes in thickness, which satisfy the resonance and anti-resonance conditions on the U-type cladding elements and the cladding tubes, respectively. Besides, the elliptical elements are introduced to achieve good single-mode performance. By studying the influences of the structure parameters on the propagation characteristics, the optimized structure parameters are obtained. The simulation results show that when the wavelength is fixed at 1550 nm, the single-polarization single-mode transmission is achieved, with the polarization extinction ratio of 25749 and minimum high-order mode extinction ratio of 174. Furthermore, the confinement loss is only 0.0015 dB/m.

Multifunctional single‐crystal tellurium core multimaterial fiber via thermal drawing and laser recrystallization

AbstractIn the field of multimaterial optical fibers, the demand for high‐performance single‐crystal core glass‐clad multimaterial optical fibers is increasing. However, the applications of single‐crystal fibers are restricted by the complex fabrication processes and the slow growth of single‐crystal materials. Here, a two‐step method is demonstrated to achieve single‐crystal tellurium (Te) core fibers with high crystal quality over the length of the fiber. This method starts with the thermal drawing of a fiber preform into polycrystalline Te core multimaterial fibers (precursor fibers) that are long and mechanically stable. A 532‐nm continuous laser is then employed to recrystallize the Te core in the precursor fiber into a single crystal state along the entire length of the fiber. Experimental studies of these single‐crystal fibers demonstrate that the single‐crystal Te core fibers possess high transmittance (>90% at 2–10 μm) and high thermoelectric performance (ZT values from 0.03 to 0.13 at 300 K temperature). They are superior to previous reports and our previous work. This method works for fabricating various single‐crystal fibers and has important applications in the field of optical fibers, functional fibers, and their integrated devices.

New Methods to Seismic Monitoring: Laboratory Comparative Study of Michelson Fiber-Optic Interferometer and Pneumatic Measurement Systems

New possibilities of vibration monitoring can be found in completely different physical approaches, where all measuring technology is currently based on sensors in the electrical domain. This paper presents two different promising alternative approaches to vibration measurement, specifically in the field of fiber-optics and pneumatic sensors. The proposed solution uses a Michelson fiber-optic interferometer designed without polarization fading and with operationally passive demodulation technique using three mutually phase-shifted optical outputs. Experimentally developed sensor systems for the registration of anthropogenic seismic phenomena were complemented by standard instrumentation for measuring seismicity used as a standard. The measurement was performed under simplified conditions using a calibrated stroke as a source of dynamic loading. In addition to alternative systems, the paper also presents the results of recalculation of the measured values in a time domain and basic relationships for the conversion to basic units derived from the SI (International System of Units) system and used internationally in the field of seismic engineering. The results presented demonstrate that even systems operating on a different physical principle have great potential to replace the existing seismic devices. The correlation coefficients for both sensory devices were high (above 0.9) and the average deviations from the measured values of the amplitude of the oscillation velocity did not exceed the value of 0.02, neither with the fiber-optic or pneumatic sensor.

Optical solitons in birefringent fibers of Kaup-Newell's equation with extended simplest equation method

The area of telecommunications has experienced a considerable growth in the last few decades due to remarkable development in the field of optical fibers. Optical solitons form the basic fabric in the area of telecommunication industry. The captivating technology of sub-pico second pulses that propagate through optical fibers is modeled with Kaup-Newell’s (KN) equation. In this paper, we introduce the KN equation without four-wave mixing (FWM) terms in birefringent fibers, we study this equation, and we obtain different types of solutions. Beside bright, dark and singular solitons, other types of solutions are obtained. Moreover, for the physical illustration of the obtained solutions, the graphs are presented.

Dental lasers applications in visible wavelength operational band

<p>There is no doubt that radiation has many side effects in our lives, so our goal in this study is to reduce our use of radiation in the diagnosis of tooth caries, and in order to achieve this goal we used the field of optical fiber in the detection of some diseases associated with oral and dental medicine. This diagnosis was accomplished by shedding light on the teeth, to be diagnosed and creating an image that allows the doctor to examine them and determine whether there are caries or any root problems. The principle is also used to detect oral cancer, fractures, and cracks in bones. This study also allows us to detect early caries, and this method saves time because it gives the diagnosis at the same time while the patient is in the treatment unit of the dental clinic. Thus the main advantages of this method are, enable the dentist to view images on the display unit attached to the clinic in real-time, compare current photos with old photos of the same patient. Also, the dentist can create a photo archive of each tooth individually and can retrieve and compare them whenever he wants. </p>

Measurement of optical fiber geometry parameters by gray distribution fitting with Gaussian function

The geometry parameters of optical fiber affect the optical transmission and mechanical properties, which are the important indexes to measure the quality of fiber. Near-field light distribution method is recommended in GB15972.20-2008 for the measurement of geometry parameters. In order to distinguish the boundary between fiber core and cladding, the method needs to illuminate the fiber. The end face of the fiber core is a bright spot with unclear edge, so the true edge of the core and cladding cannot be accurately judged. In this paper, the distribution of mode field in optical fiber is analyzed. Theoretically, the solution of electromagnetic vector of mode field satisfies Bessel function, but Gaussian function can also be used under approximate conditions. Therefore, Gaussian function is used to fit the distribution of the fiber core in this paper, and the real edge of the fiber core and cladding can be obtained from the Gaussian function after fitting. This method is a further improvement on the measurement method of GB15972.20-2008. The experimental results show that when the cutting effect of the fiber is not good or the imaging quality is poor, the Gaussian function method fitting with mode distribution can still ensure the repeatability of the measurement and the stability of the measured data.

Detection and Quantization Technique of Optical Distributed Acoustic Coupling Based on φ-OTDR

The detection of multiple acoustic disturbances by optical fiber is a hot research topic in the field of optical fiber sensing. This paper considers adopting an optical distributed acoustic sensing (DAS) system to detect multiple acoustic disturbances, proposes a new approach to processing the DAS signal based on time-space average in frequency domain, and overcomes the randomness of DAS time domain signal. Finally, it obtains a functional model of single-frequency (50–1 000 Hz) sound pressure level and DAS signal intensity, and also the cut-off frequency of acoustic disturbance is detected by DAS system.

The Effect of Spatial Mode Distribution on Coupling Efficiency of Single-Mode Fiber: Theoretical Analysis and Experimental Verification

In this study, Zernike polynomials and optical fiber field theory are applied to build a mathematical model of coupling efficiency (CE) and spatial mode of aberrations. The theory built in this paper can be used to quickly calculate the CE affected by a single aberration as well as the aberrations caused by atmospheric turbulence. The aberrations are classified based on Zernike polynomials and the effects of aberrations on CE of different types and different spatial frequencies are analyzed. The influence of the effects of AO system residual errors is also analyzed. Adaptive optics (AO) equipment is applied to build a system on which the proposed theory was tested; the experimental results validate the theoretical analysis.

RECENT DEVELOPMENTS AND APPLICATIONS OF POLARIZATION-MAINTAINING FIBER LOOP MIRRORS

In the polarization-maintaining fiber loop mirrors (PM-FLM), the birefringence of the polarization-maintaining fiber (PMF, one of the typical PMFs is the high-birefringence fiber) introduces phase difference and results in time-delay interference between the two counterpropagating waves. Hence, the transmission (or the reflection) spectrum is characterized by comb filtering, which is easily tuned and is independent of input wave polarization. Based on the properties, the PM-FLM is widely used in the field of optical fiber sensing and communication. This article analyzes the comb filtering theory of the PM-FLM and discusses the recent typical applications of the PM-FLM in the field of multiwavelength fiber laser (MFL), all-optical signal processing (AOSP), optimized performance of the erbium doped fiber amplifier (EDFA), and demodulation of fiber Bragg grating (FBG) sensors in detail.

PHOTONIC CRYSTAL FIBRES DESIGN USING A MULTICRITERIA BASED SOFTWARE

The single-mode optical fiber used currently in communication systems starts showing many limitations especially for the high rates. Several physical phenomena related to the optical propagation are the cause of these limitations. The use of photonic crystal fibers (PCF) makes it possible to control most of these phenomena. In this paper, a multicriteria method is used for the design of the photonic crystal fiber with the user-defined optical proprieties. This method combines the deductive and the inductive learning and it is introduced for the first time in the field of optical fibers. This multicriteria method proves to be a powerful tool for the PCF fibers design.

Rotational Doppler-effect due to selective excitation of vector-vortex field in optical fiber

Experimental demonstration of rotational Doppler-effect due to direct and simultaneous excitation of orthogonal elliptically-polarized fundamental and vortex modes in a two-mode optical fiber is presented here. The rotation frequency and the trajectory of the zero-intensity point in the two-mode fiber output beam measured as a function of analyzer rotation matches with the S-contour of polarization singularity in the beam, identified via Stokes parameter measurement. The characteristics of the S-contour around the C-point in the output beam is also measured as a function of rotating Dove prism and half-wave plate - Dove prism combination to highlight the role of polarization modifying components on the observed rotational Doppler-effect of vector-vortex beams.

Some aspects of theoretical analysis of the light propagation in an elliptical optical fiber

The paper presents the results of theoretical analysis of the propagation of the electromagnetic field in optical fiber with an elliptic core. Due to the elliptic symmetry of the core the analysis had to be carried out in an elliptic coordinate system. This analysis has shown that the functions describing the z-component of the electric field satisfy the Mathieu equations. The presented results of the theoretical analysis are original and have not published so for.

Percutaneous coronary angioscopy: methods, findings, and therapeutic implications.

The development and clinical implementation of percutaneous coronary angioscopy represents an engineering triumph, blending the newest technologies and materials in the field of fiberoptics with the most advanced techniques of balloon angioplasty catheter materials and construction. Current devices provide a safe method for acquiring excellent quality images of the coronary arteries. This is due to major advances in catheter alignment techniques allowing coaxial positioning of the angioscope in the relatively tortuous coronary arteries. Additional development is needed to further refine the degree of operator control over the field of view, which would also reduce procedure duration. The percutaneous coronary angioscope is currently a functional device for investigators attempting to correlate the morphology of atherosclerotic lesions and clinical coronary artery disease. Confirmation of the value of the angioscope as a clinically useful device for routine application in the diagnosis and management of cardiovascular disease will depend upon the results of further studies.

Optical Componentry Utilized in Field Trial of Single-Mode Fiber Long-Haul Transmission

Realization of large-capacity long-haul transmission systems is now quite promising due to rapid development in the field of optical fibers. The paper describes single-mode fiber optical components for use in the above-mentioned system. In particular, LD modules, optical connectors are most important for construction of a practical system. Thus, they are explained in detail along with their development procedures. Important field trial results of these components are also presented.

Optical componentry utilized in field trial of single-mode fiber long-haul transmission

Realization of large-capacity long-haul transmission systems is now quite promising due to rapid development in the field of optical fibers. This paper describes single-mode fiber optical components for use in the above-mentioned system. In particular, LD modules and optical connectors are most important for construction of a practical system. Thus, they are explained in detail along with their development procedures. Important field trial results of these components are also presented.