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This Open Access book discusses an extension to low-coherence interferometry by dispersion-encoding. The approach is theoretically designed and implemented for applications such as surface profilometry, polymeric cross-linking estimation and the determination of thin-film layer thicknesses. During a characterization, it was shown that an axial measurement range of 79.91 µm with an axial resolution of 0.1 nm is achievable. Simultaneously, profiles of up to 1.5 mm in length were obtained in a scan-free manner. This marked a significant improvement in relation to the state-of-the-art in terms of dynamic range. Also, the axial and lateral measurement range were decoupled partially while functional parameters such as surface roughness were estimated. The characterization of the degree of polymeric cross-linking was performed as a function of the refractive index. It was acquired in a spatially-resolved manner with a resolution of 3.36 x 10-5. This was achieved by the developmentof a novel mathematical analysis approach.

This Spotlight is intended to pass on some nuggets of knowledge about how to go about setting up an optical alignment using a laser and some tricks to use to make life easier. There are other topics that are important to grasp, topics that may have been presented in lectures but not faced in reality - such as chromatic effects and collimation. This text is not intended to be rigorously scientific in its approach but more as a companion on your optics journey.

The main objective of this book is to present the basic theoretical principles and practical applications for the classical interferometric techniques and the most advanced methods in the field of modern fringe pattern analysis applied to optical metrology. A major novelty of this work is the presentation of a unified theoretical framework based on the Fourier description of phase shifting interferometry using the Frequency Transfer Function (FTF) along with the theory of Stochastic Process for the straightforward analysis and synthesis of phase shifting algorithms with desired properties such as spectral response, detuning and signal-to-noise robustness, harmonic rejection, etc.

Optical interference plays a prominent role in scientific discovery and modern technology. Historically, optical interference was instrumental in establishing the wave nature of light. Nowadays, optical interference continues to be of great importance in areas such as spectroscopy and metrology. Thus far, the physical optics literature has discussed the interference of optical waves with the same single frequency (i.e., homodyne interference) and the interference of optical waves with two different frequencies (i.e., heterodyne interference), but it hardly ever deals with the interference of optical waves whose frequencies are continuously modulated (i.e., frequency-modulated continuous-wave int- ference). Frequency-modulated continuous-wave (FMCW) interference, which was originally investigated in radar in the 1950s, has been recently introduced in optics. The study of optical FMCW interference not only updates our kno- edge about the nature of light but also creates a new advanced technology for precision measurements. This book introduces the principles, applications, and signal processing of optical FMCW interference. The layout of this book is straightforward. Chapter 1 gives a short introduction to optical FMCW interferometry by considering the historical development, general concepts, and major advantages provided by this new technology. Chapter 2 focuses on the principles of optical FMCW interference. Three different versions of optical FMCW interference— sawtooth-wave optical FMCW interference, triangular-wave optical FMCW interference, and sinusoidal-wave optical FMCW interference—are discussed in detail. Moreover, multiple-beam optical FMCW interference and multip- wavelength optical FMCW interference are also discussed by this chapter.

This book is for those who have some knowledge of optics, but little or no previous experience in interferometry. Accordingly, the carefully designed presentation helps readers easily find and assimilate the interferometric techniques they need for precision measurements. Mathematics is held to a minimum, and the topics covered are also summarized in capsule overviews at the beginning and end of each chapter. Each chapter also contains a set of worked problems that give a feel for numbers.The first five chapters present a clear tutorial review of fundamentals. Chapters six and seven discuss the types of lasers and photodetectors used in interferometry. The next eight chapters describe key applications of interferometry: measurements of length, optical testing, studies of refractive index fields, interference microscopy, holographic and speckle interferometry, interferometric sensors, interference spectroscopy, and Fourier-transform spectroscopy. The final chapter offers suggestions on choosing and setting up an interferometer.