Download or read book Pressure and Temperature Sensors Manufactured Using a Novel Technique for Generating Extrinsic Fabry p rot Interferometer Diaphragms written by McGuinness Fintan and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book MEMS Based Fabry Perot Pressure Sensor and Non adhesive Integration on Optical Fiber by Anodic Bonding written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Optical pressure sensor based on the principle of Fabry Perot interferometry have been developed and fabricated using the technique of silicon-to-silicon anodic bonding. This MEMS based Fabry Perot pressure sensor is then integrated onto an optical fiber by a novel technique of anodic bonding. In this novel technique of anodic bonding we use ultra6thin silicon of thickness 10æm to bond the optical fiber to the sensor. Tensile bond strength measurements are performed to characterize the fiber to silicon bond as a function of bonding temperature. The ultra-thin silicon plays the role of a stress reducing layer which helps bonding an optical fiber to silicon having conventional thickness. The pressure sensing membrane is formed by 8æm thick ultra-thin silicon which allows having membrane with uniform thickness over the entire wafer and eliminates the need for bulk etching. The pressure sensor integrated onto an optical fiber is tested for static response and for response with change in ambient temperature. The sensor response changes with the temperature due to change in the physical dimension of the sensor. Also, the effect of multimode fiber on the fringe visibility of the interferometer is studied. The fringe visibility of the sensor is lower than the theoretical fringe visibility due to the fact that one of the mirrors of the Fabry Perot interferometer formed by silicon membrane is not flat but a curved surface.

Download or read book Integration of Electronic and Optical Techniques in the Design and Fabrication of Pressure Sensors written by Ivan Padron and published by . This book was released on 2010 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the introduction of micro-electro-mechanical systems fabrication methods, piezoresistive pressure sensors have become the more popular pressure transducers. They dominate pressure sensor commercialization due to their high performance, stability and repeatability. However, increasing demand for harsh environment sensing devices has made sensors based on Fabry-Perot interferometry the more promising optical pressure sensors due to their high degree of sensitivity, small size, high temperature performance, versatility, and improved immunity to environmental noise and interference. The work presented in this dissertation comprises the design, fabrication, and testing of sensors that fuse these two pressure sensing technologies into one integrated unit. A key innovation is introduction of a silicon diaphragm with a center rigid body (or boss), denoted as an embossed diaphragm, that acts as the sensing element for both the electronic and optical parts of the sensor. Physical principles of piezoresistivity and Fabry-Perot interferometry were applied in designing an integrated sensor and in determining analytic models for the respective electronic and optical outputs. Several test pressure sensors were produced and their performance was evaluated by collecting response and noise data. Diaphragm deflection under applied pressure was detected electronically using the principle of piezoresistivity and optically using Fabry-Perot interferometry. The electronic part of the sensor contained four p-type silicon piezoresistors that were set into the diaphragm. They were connected in a Wheatstone bridge configuration for detecting strain-dependent changes in resistance induced by diaphragm deflection. In the optical part of the sensor, an optical cavity was formed between the embossed surface of the diaphragm and the end face of a single mode optical fiber. An infrared laser operating at 1.55 was used for optical excitation. Deflection of the diaphragm, which causes the length of the optical cavity to change, was detected by Fabry-Perot interference in the reflected light. Data collected on several sensors fabricated for this dissertation were shown to validate the theoretical models. In particular, the principle of operation of a Fabry-Perot interferometer as a mechanism for pressure sensing was demonstrated. The physical characteristics and behavior of the embossed diaphragm facilitated the integration of the electronic and optical approaches because the embossed diaphragm remained flat under diaphragm deflection. Consequently, it made the electronic sensor respond more linearly to applied pressure. Further, it eliminated a fundamental deficiency of previous applications of Fabry-Perot methods, which suffered from non-parallelism between the two cavity surfaces (diaphragm and fiber), owing to diaphragm curvature after pressure was applied. It also permitted the sensor to be less sensitive to lateral misalignment during the fabrication process and considerably reduced back pressure, which otherwise reduced the sensitivity of the sensor. As an integrated sensor, it offered two independent outputs in one sensor and therefore the capability for measurements of: (a) static and dynamic pressures simultaneously, and (b) two different physical quantities such as temperature and pressure.

Download or read book International Aerospace Abstracts written by and published by . This book was released on 1996 with total page 1012 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fabrication of a Novel Optical Pressure Sensor Using Fabry Perot Interferometry written by Praveen Pandojirao-Sunkojirao and published by . This book was released on 2004 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fabry Perot Fiber Optic Temperature Sensor System written by and published by . This book was released on 1997 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modeling and Characterization of a Fabry Perot Pressure Sensor written by Shruthika Prasanna and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Fabry-Perot interferometers (FPIs) have been used as sensing elements for pressure transducers in many applications. Most of the current FPI pressure sensors measure amplitude changes of the reflected signals from a deformable diaphragm. A new technique to design an FPI pressure sensor has been proposed in this thesis. The proposed methodology aims to maximize the sensitivity by measuring frequency shifts and optimize the dimensions of the sensors for various materials and applications. The sensor diaphragm is built directly on the end surface of an optical fiber with a sacrificial layer introducing the required FPI cavity height. The resulting sensor detects frequency shifts transduced by pressure variations deforming the diaphragm. The sensor is modeled on two theories and a methodology is derived combining an iterative analysis between the mechanical characteristics and the optical performance to achieve optimal sensitivity. Applying this methodology, design parameters for different applications are extracted. The practical issues of designing a fiber optic Fabry-Perot pressure sensor have been investigated. Structural modifications are introduced to optimize the dimensions without compromising sensitivity. A bossed diaphragm structure is proposed to eliminate the effects of optical scattering from the reflection surface. Different configurations of the bossed structures under conditions of diverse diaphragm supports have been studied. The optical performance and sensor dimension combination that yields in the maximum sensitivity has been achieved. The modeling-based methodology has been adopted to choose design parameters for different materials, catering to the requirements of small sensor dimensions over numerous different applications.

Download or read book Physics Briefs written by and published by . This book was released on 1991 with total page 1120 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mixed signal Processor for a Fabry Perot Interferometric Fiber Optic Pressure Sensor written by Roberto Sadkowski and published by . This book was released on 1994 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Study of a MEMS Fiber optic Pressure Sensor Based on Optical Interferometry written by Pedro Cordero Meza and published by . This book was released on 2017 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main focus of this thesis is the development of a MEMS optical pressure sensor capable of giving real-time, accurate measurements to a mid-high pressure range. Some traditional devices for acquisition of parameters such as pressure or temperature have proven to be insufficient to the demands of the markets of research and manufacturing. State-of-the-art sensing technology has led to the construction of more reliable configurations that push the limits of traditional devices. Using micro-machined components is a suitable approach for applications that show restrictions just as limited space, noise measurement or interference created by the inaccuracy of electronic components that are not suited to be in close contact with the sensing medium. A study of the current optical based technologies revealed the current use of extrinsic Fabry - Perot interferometers in the fields of medical, biotechnological and industrial applications. Each field presents a general specific limitation, given the nature of its environment. These mostly include low pressure and temperature ranges, non-protected sensors or super sensitive, expensive devices., The operation of this sensor comprises a non-emissive, optically powered device that shows precision measurements and immunity to electromagnetic interference. Tested over a mid-high pressure range that shows a 20% improvement over the devices found in literature. This sensor is the result of the coupling of a multimode silica optical fiber, a MEMS pressure sensor with a thin silicon film and a stainless steel housing for packaging. A theoretical analysis and response simulations were used previous and along the process of construction and testing of the device. This analysis was followed by an assessment on the materials that were suitable for the assembling of the device, plus the pertinent modifications for each component that allowed a proper coupling. Several tests were done previous to the final assembly of the device, where calibration, alignment and limitations of the device were studied previous to determine the sensor's response. The experiments were done at the SimsLab of the University of Waterloo, using a pressure chamber with direct connection to the housing of the sensor to avoid pressure leaks. The sensor's properties include a silicon thin film with a thickness of 34 micrometers, an optical fiber with a core diameter of 125 micrometers, protected by a ceramic ferrule to provide stability and rigidity to the fiber. The fiber is part of a coupler that splits the optical signal between the input and output beams. The output leg of the coupler then sends the information to an OSI (Optical Sensor Interrogator) which is a set of electronics that use a photo detector to break the light into its spectral components, analyzing fringes and converting the photons into electrons which are digitized as a function of the wavelength and read out via a USB port into a host computer. A LabView program then converts the optical response to a value in millivolts that can be directly related to the changes in pressure that are detected by the deflective silicon membrane. A complete characterization of the sensor's response was carried out. An averaged sensitivity of 1.3768 mV / psi over a range of 0 - 100 psi was found. An accuracy of 1.25 psi per 0.1 mV was established. The Noise Equivalent Pressure measurement could to be neglected over the accuracy that is limited by the capacity of the electronics. In summary, an Optical MEMS pressure sensor was developed. This device is capable of being tested in laboratory and manufacturing-like simulated environments. The pressure measurements acquired during this project assisted the base for a future prototype to be developed in enhancing the pressure range in a harsh environment, with elevated temperature. Proof-of-concept data was gathered and analyzed so further advances can be reached on micro-fabrication and optical techniques.

Download or read book Fiber Optic Fabry Perot Temperature Sensors written by H. F. Taylor and published by . This book was released on 1989 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Handbook of Modern Sensors written by Jacob Fraden and published by Springer Science & Business Media. This book was released on 2006-04-29 with total page 596 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seven years have passed since the publication of the previous edition of this book. During that time, sensor technologies have made a remarkable leap forward. The sensitivity of the sensors became higher, the dimensions became smaller, the sel- tivity became better, and the prices became lower. What have not changed are the fundamental principles of the sensor design. They are still governed by the laws of Nature. Arguably one of the greatest geniuses who ever lived, Leonardo Da Vinci, had his own peculiar way of praying. He was saying, “Oh Lord, thanks for Thou do not violate your own laws. ” It is comforting indeed that the laws of Nature do not change as time goes by; it is just our appreciation of them that is being re?ned. Thus, this new edition examines the same good old laws of Nature that are employed in the designs of various sensors. This has not changed much since the previous edition. Yet, the sections that describe the practical designs are revised substantially. Recent ideas and developments have been added, and less important and nonessential designs were dropped. Probably the most dramatic recent progress in the sensor technologies relates to wide use of MEMS and MEOMS (micro-electro-mechanical systems and micro-electro-opto-mechanical systems). These are examined in this new edition with greater detail. This book is about devices commonly called sensors. The invention of a - croprocessor has brought highly sophisticated instruments into our everyday lives.

Download or read book Structural Health Monitoring of Civil Infrastructure Systems written by Vistasp M. Karbhari and published by Elsevier. This book was released on 2009-08-25 with total page 553 pages. Available in PDF, EPUB and Kindle. Book excerpt: Structural health monitoring is an extremely important methodology in evaluating the 'health' of a structure by assessing the level of deterioration and remaining service life of civil infrastructure systems. This book reviews key developments in research, technologies and applications in this area of civil engineering. It discusses ways of obtaining and analysing data, sensor technologies and methods of sensing changes in structural performance characteristics. It also discusses data transmission and the application of both individual technologies and entire systems to bridges and buildings.With its distinguished editors and international team of contributors, Structural health monitoring of civil infrastructure systems is a valuable reference for students in civil and structural engineering programs as well as those studying sensors, data analysis and transmission at universities. It will also be an important source for practicing civil engineers and designers, engineers and researchers developing sensors, network systems and methods of data transmission and analysis, policy makers, inspectors and those responsible for the safety and service life of civil infrastructure. - Reviews key developments in research, technologies and applications - Discusses systems used to obtain and analyse data and sensor technologies - Assesses methods of sensing changes in structural performance

Download or read book Photonic Microresonator Research and Applications written by Ioannis Chremmos and published by Springer. This book was released on 2010-06-09 with total page 515 pages. Available in PDF, EPUB and Kindle. Book excerpt: The technology surrounding the design and fabrication of optical microresonators has matured to a point where there is a need for commercialization. Consequently, there is a need for device research involving more advanced architectures and more esoteric operating principles. Photonic Microresonator Research and Applications explores advances in the fabrication process that enable nanometer waveguide separations, exceptionally smooth surfaces essential to reach Q factors in the order of 106- 108 and high index contrast materials.

Download or read book Handbook of Advanced Nondestructive Evaluation written by Nathan Ida and published by Springer. This book was released on 2019-07-29 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This handbook is a comprehensive source of information on all aspects of non-destructive testing (NDT), for use by professionals, educators, and most of all, by the practitioners of testing. The art of NDT consists of dozens of methods, some classical, and some emerging. As the pace of industrial work and discovery intensifies and materials are utilized to their physical limits, the role of NDT becomes ever more important. As a result, the methods of testing are themselves evolving, and it is the intent of this book to capture this evolution. Handbook of Modern Non-Destructive Testing broadens the scope from traditional books on the subject. In addition to classical, emerging and exotic methods of evaluation, the book will also cover the use of NDT techniques in other fields, such as archaeology or resource exploration. With contributions from experts in all areas of the field, the reader will find balanced coverage of a variety of testing methods, with no bias against or endorsements of any particular method. The book treats many areas in depth, covering all aspects of testing, and will include case studies where appropriate. Additional coverage of statistical methods and their use, as well as simulations‘ role in testing and test design, are included.

Download or read book Lab on Fiber Technology written by Andrea Cusano and published by Springer. This book was released on 2014-07-29 with total page 377 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on a research field that is rapidly emerging as one of the most promising ones for the global optics and photonics community: the “lab-on-fiber” technology. Inspired by the well-established "lab on-a-chip" concept, this new technology essentially envisages novel and highly functionalized devices completely integrated into a single optical fiber for both communication and sensing applications. Based on the R&D experience of some of the world's leading authorities in the fields of optics, photonics, nanotechnology, and material science, this book provides a broad and accurate description of the main developments and achievements in the lab-on-fiber technology roadmap, also highlighting the new perspectives and challenges to be faced. This book is essential for scientists interested in the cutting-edge fiber optic technology, but also for graduate students.

Download or read book Nanotechnology Enabled Sensors written by Kourosh Kalantar-zadeh and published by Springer Science & Business Media. This book was released on 2007-09-19 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanotechnology provides tools for creating functional materials, devices, and systems by controlling materials at the atomic and molecular scales and making use of novel properties and phenomena. Nanotechnology-enabled sensors find applications in several fields such as health and safety, medicine, process control and diagnostics. This book provides the reader with information on how nanotechnology enabled sensors are currently being used and how they will be used in the future in such diverse fields as communications, building and facilities, medicine, safety, and security, including both homeland defense and military operations.