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1 – 10 of 285It is important to monitor wrist four direction movements (flexion, extension, adduction and abduction) for hand healthcare, wrist rehabilitation and upper limb exercise, and so…
Abstract
Purpose
It is important to monitor wrist four direction movements (flexion, extension, adduction and abduction) for hand healthcare, wrist rehabilitation and upper limb exercise, and so on. The purpose of this study is to develop a quadri-directional optical bending sensor that integrated wearable device technology in a smart glove to detect wrist four direction movements.
Design/methodology/approach
The quadri-directional optical bending sensor was designed with a microcontroller board, a Bluetooth wireless module, a side-emitting polymeric optical fibre (POF), an infrared light emitting diode and four phototransistors. A linear equation was deduced to calculate bending angle from detecting sensor value of Arduino microcontroller. The bending angle values could be seen by the smartphone screen, so the system has a good human–machine interface function.
Findings
The light emission by macro-bending of the side-emitting POFs that the transmittance of the outer side is greater than the inner. The bending POFs lateral emission phenomenon integrated with phototransistors on the edge is suitable for the development of bending sensors.
Originality/value
This study is to develop a novel quadri-directional optical bending sensor to replace two bi-direction sensors or four uni-direction sensors for wrist four direction movements monitoring.
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D. Křemenáková, J. Militký, B. Meryová and V. Lédl
The main role of polymer optical fibers is to transmit light or optical signal to a specified spot. In the case of side emitting plastic optical fibers the light leaks out from…
Abstract
The main role of polymer optical fibers is to transmit light or optical signal to a specified spot. In the case of side emitting plastic optical fibers the light leaks out from their surface. This sidelight can be used for creation of optically active textile structures providing opportunities to highlight people and objects without the need for external exposure. Due to the transmission loss, the intensity of radiation emitted in any direction decays exponentially along the fiber axis with increasing distance from the light source. The main aim of this contribution is evaluation of side emitting plastic optical fibers light intensity in dependence on the distance from light source. The special device for measurement of surface and cross section light intensity in various distances from light source was developed. The dependence of surface and cross section light intensity on the distance from light source will be expressed by the exponential type model with attenuation factor as the rate parameter. The influence of the optical fiber type and diameter on the attenuation factor of surface and cross section light intensity will be quantified.
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Dana Křemenáková, Barbora Meryová, Jiří Militký and Vít Lédl
The main aim of this work is evaluation of side emitting plastic optical fibers (POF) illumination intensity changes in dependence on the distance from light source. Illumination…
Abstract
The main aim of this work is evaluation of side emitting plastic optical fibers (POF) illumination intensity changes in dependence on the distance from light source. Illumination intensity is measured along straight and bent fibers. The special devices for these measurements realization are described. The dependence of light intensity on the distance from light source for straight optical fibers is expressed by the exponential type model with two parameters, i.e. illumination intensity at the input into fiber and fiber attenuation factor. Preliminary results of measurement of light intensity in bent state are discussed. Influence of ratio between fiber diameter and bending cylinder diameter on the illumination intensity changes is presented.
Elzbieta Marszalec and Janusz Marszalec
Integration of lasers and fibre optics into robotic systems provides new opportunities in sensing and material processing. Increased productivity and application of robots in…
Abstract
Integration of lasers and fibre optics into robotic systems provides new opportunities in sensing and material processing. Increased productivity and application of robots in hostile environments are other possibilities.
Zi-qian Bai, Jeanne Tan, Clare Frances Johnston and Xiao-Ming Tao
The purpose of this paper is to investigate how electronic components can be utilized and integrated into polymeric optical fibre (POF) textiles to refine the design aesthetic…
Abstract
Purpose
The purpose of this paper is to investigate how electronic components can be utilized and integrated into polymeric optical fibre (POF) textiles to refine the design aesthetic, tactile quality and initiate the interaction of textiles with the users; and to study the design process of interactive products by using a novel design process model.
Design/methodology/approach
Fashion and textile design methods, textile technology are used in combination with modern technologies such as laser engraving, sensing, short-distance communication technology, throughout the entire process of development of interactive photonics creations.
Findings
The results of evaluation indicate that the engineered prototypes can enhance the interactive function of interior furnishing. The usability of interactive POF cushions is optimized by innovative design methods considering both design and technology.
Originality/value
This research explores to combine knowledge from different disciplines, including textile, electronics, sensor and laser to create interactive soft furnishings. The inter-disciplinary research provides a new perspective on how POF fabric can be utilized as a new media to change the way people interact with their living surroundings. The interior soft furnishings are no longer unresponsive to people, but can react to them, adapt to their behaviors, change color according to their preferences and therefore merge into our daily life. The developed prototypes reshape interior soft furnishing, and therefore have both theoretical and practical significance.
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Roger Main gives a four‐part report on the optical technologies which are playing an increasingly important role in sensor development.
J. Heilala, K. Keränen, J.‐T. Mäkinen, O. Väätäinen, K. Kautio, P. Voho and P. Karioja
The aim of the research was to evaluate the concept that utilizes structured planar substrates based on low temperature co‐fired ceramics (LTCC) as a precision platform for the…
Abstract
Purpose
The aim of the research was to evaluate the concept that utilizes structured planar substrates based on low temperature co‐fired ceramics (LTCC) as a precision platform for the passive alignment of a multimode fiber and wide‐stripe diode laser.
Design/methodology/approach
Presents the manufacturing process for realisation of 3D precision structures, heat dissipation structures and a cooling channel into the LTCC substrate. The developed methodology for 3D modelling and simulation of the system was used to optimize structures, materials and components in order to achieve optimal performance for the final product and still maintain reasonably low fabrication costs. The simulated optical coupling efficiency and alignment tolerances were verified by prototype realization and characterization.
Findings
The achieved passive alignment accuracy allows high coupling efficiency realisations of multimode fiber pigtailed laser modules and is suitable for mass production.
Research limitations/implications
Provides guidance in the design of LTCC precision platforms for passive alignment and presents a hybrid simulation method for photonics module concept analysis.
Practical implications
The three‐dimensional shape of the laminated and fired ceramic substrate provides the necessary alignment structures including holes, grooves and cavities for the laser to fiber coupling. Thick‐film printing and via punching can be incorporated in order to integrate electronic assemblies directly into the opto‐mechanical platform.
Originality/value
Introduces the LTCC 3D precision structures for photonics modules enabling passive alignment of multimode fiber pigtailed laser with high efficiency optical coupling. Demonstrates the hybrid simulation methodology for concept analysis.
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S. O'Keeffe, C. Fitzpatrick, E. Lewis and A.I. Al‐Shamma'a
The purpose of this paper is to provide a detailed review of radiation dosimetry techniques based on optical fibre dosimeters. It presents a comprehensive bibliography of the…
Abstract
Purpose
The purpose of this paper is to provide a detailed review of radiation dosimetry techniques based on optical fibre dosimeters. It presents a comprehensive bibliography of the current research activities in the area.
Design/methodology/approach
A range of published work on optical fibre radiation dosimeters are presented, with the merits and limitations discussed. Each radiation dosimetry technique is discussed in turn, providing examples of dosimeters using such techniques reviewed. The main focus is on gamma radiation although other radiation dosimeters are considered.
Findings
This paper provides information on the wide range of research activity into radiation dosimeters. The dose ranges of these dosimeters are presented, along with the advantages and disadvantages of different dosimetry techniques.
Originality/value
A comprehensive review of published research in the area of solid radiation dosimetry is presented in this paper. It provides an individual with a review of the various techniques used and most recent research in that field.
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Mohd Anwar Zawawi, Sinead O'Keffe and Elfed Lewis
The purpose of this paper is to provide a comparative review of intensity‐modulated fiber optic sensors with non‐optical sensors for health monitoring applications, from the…
Abstract
Purpose
The purpose of this paper is to provide a comparative review of intensity‐modulated fiber optic sensors with non‐optical sensors for health monitoring applications, from the current research activities in the area.
Design/methodology/approach
A range of published research work in sensor design for four different health monitoring applications, including, lumbar spine bending, upper and lower limb motion tracking, respiration and heart rate monitoring, are presented and discussed in terms of their respective advantages and limitations.
Findings
This paper provides information on the various types of sensors applied into the health monitoring area. The sensing techniques of the fiber optic sensor for the stated applications are focused and compared in details to highlight their contributions.
Originality/value
A comparative review of published work is illustrated in an informative table content, to allow a clear idea of the current sensing approaches for health monitoring applications.
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Alexander D. Klose and Andreas H. Hielscher
This paper sets out to give an overview about state‐of‐the‐art optical tomographic image reconstruction algorithms that are based on the equation of radiative transfer (ERT).
Abstract
Purpose
This paper sets out to give an overview about state‐of‐the‐art optical tomographic image reconstruction algorithms that are based on the equation of radiative transfer (ERT).
Design/methodology/approach
An objective function, which describes the discrepancy between measured and numerically predicted light intensity data on the tissue surface, is iteratively minimized to find the unknown spatial distribution of the optical parameters or sources. At each iteration step, the predicted partial current is calculated by a forward model for light propagation based on the ERT. The equation of radiative is solved with either finite difference or finite volume methods.
Findings
Tomographic reconstruction algorithms based on the ERT accurately recover the spatial distribution of optical tissue properties and light sources in biological tissue. These tissues either can have small geometries/large absorption coefficients, or can contain void‐like inclusions.
Originality/value
These image reconstruction methods can be employed in small animal imaging for monitoring blood oxygenation, in imaging of tumor growth, in molecular imaging of fluorescent and bioluminescent probes, in imaging of human finger joints for early diagnosis of rheumatoid arthritis, and in functional brain imaging.
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