In recent years, fiber optic sensors have developed from the laboratory research and development stage to practical applications. The market for fiber optic sensor technology may be divided into two broad categories of sensors: intrinsic and extrinsic. Intrinsic sensors are used in medicine, defense, and aerospace applications, and they can be used to measure temperature, pressure, humidity, acceleration, and strain. Extrinsic sensors are used in telecommunications to monitor the status and performance of the optical fibers within a network. The purpose of this updated book is to provide a tutorial overview on fiber optic sensor principles and applications.
In particular, the updated and new chapters reflect both the recent advances in fiber optic sensor technology itself (such as the application of photonic crystal fibers to fiber optic gyroscopes and fiber optic grating inscription by femtosecond laser illumination) and new application opportunities that have great potential (e.g., fiber optic sensors provide for medical treatment that is minimally invasive). This text covers a wide range of topics in fiber optic sensors, although it is by no means complete. All chapters are written by experts in the field. Nine chapters were included in the previous version of the book, but have been updated.
Chapter 5 and Chapter 11 are newly added chapters. Chapter 5 (harsh environment fiber optic grating sensors inscribed by femtosecond laser illumination) introduces state-of-the-art fiber optic grating sensor technology and Chapter 11 (fiber optic chemical/biological sensors) reviews the recent advances in this fast growing application sector. Chapter 1 gives an overview of fiber optic sensors that includes the basic concepts, historical development, and some of the classic applications. This overview provides the essential background material needed to facilitate the objectives of later chapters.
Chapter 2 deals with fiber optic sensors based on Fabry–Perot interferometers. The major merits of this type of sensor include high sensitivity, compact size, and no need for fiber couplers. The high sensitivity and multiplexing capabilities of this type of fiber optic sensor make it particularly well suited for smart structure monitoring applications. Chapter 3 introduces a polarimetric fiber optic sensor. The polarization state of light that propagates in an optical fiber can be changed through external perturbation. By employing polarization-maintaining fiber, the effect of polarization changes induced by external perturbation can be exploited for sensing applications. One of the major features of this type of sensor is that it offers an excellent trade-off between sensitivity and robustness. Chapter 4 reviews fiber-grating-based fiber optic sensors. Fiber grating technology (Bragg and long-period gratings) is a very powerful tool for highsensitivity, quasi-distributed sensing. Chapter 5 is a newly added chapter (replacing the original Chapter 5 on distributed fiber optic sensors) that introduces a new type of fiber grating inscribed by femtosecond laser irradiation.
This type of fiber grating sensor offers the advantage of harsh environment sensing because the gratings are not erased at high temperatures. Additionally, the fibers do not need to be doped with Ge as they are when a grating is written using UV. As a result, these new gratings can be produced as almost any type of fiber (such as photonic crystal fibers and sapphire fibers), which greatly increases the number of applications to which they can be applied. Chapter 6 discusses fiber optic specklegram sensors. A fiber specklegram is formed by the interference between different modes that propagate in multimode optical fibers. Since the specklegram is formed by commonmode interference, it can have a very high sensitivity to some environmental factors (such as bending) and less sensitivity to others (such as temperature fluctuations).
Thus, it is a very unique type of fiber optic sensor. Chapter 7 introduces interrogation techniques for fiber optic sensors. This chapter emphasizes the physical effects in optic fibers when a fiber is subjected to external perturbations. Chapter 8 focuses on fiber gyroscope sensors. First, the basic concepts are introduced. Fiber gyroscope sensors are based on the interference between two light beams that propagate in opposite directions in a fiber loop. Since a large number of turns are used, a very high sensitivity can be realized. Second, practical issues related to fiber optic gyroscopes, such as modulation and winding techniques, are reviewed. The content of this chapter has been substantially updated in this new version to include (1) polarization analysis of a fiber optic gyroscope (FOG) sensor coil and (2) recent advances in winding technology.
Chapter 9 introduces a fiber optic hydrophone system. This chapter deals with several key issues, such as interferometer configuration, interrogation/ demodulation schemes, multiplexing architecture, polarization fading mitigation, and system integration. It also includes discussions on related technologies, such as fiber optic amplifiers, wavelength division multiplexing components, optical isolators, and circulators. Chapter 10 discusses the applications of fiber optic sensor technology to structural health monitoring, including bridges, dams, the electric power industry, etc. Chapter 11 is a newly added chapter that provides a review on fiber optic chemical and biomedical sensors, which represent a fast growing market for fiber optic sensing technology. This text will be a useful reference for researchers and technical staffs engaged in the field of fiber optic sensors. The book can also serve as a viable text or reference book for engineering students and professors who are interested in fiber optic sensors.
Download Fiber Optic Sensors Second Edition by Shizhuo Yin and Paul B. Ruffin and Francis T. S. Yu easily in PDF format for free.