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Über dieses Buch

This book presents a self-contained treatment of the principles and major applications of digital hologram recording and numerical reconstruction (Digital Holography). This second edition has been significantly revised and enlarged. The authors have extended the chapter on Digital Holographic Microscopy to incorporate new sections on particle sizing, particle image velocimetry and underwater holography. A new chapter now deals comprehensively and extensively with computational wave field sensing. These techniques represent a fascinating alternative to standard interferometry and Digital Holography. They enable wave field sensing without the requirement of a particular reference wave, thus allowing the use of low brilliance light sources and even liquid-crystal displays (LCD) for interferometric applications.

Inhaltsverzeichnis

Frontmatter

Chapter 1. Introduction

Abstract
The recording and storage of full-parallax 3D images was and is a recurring goal of science and engineering since the first photographs were made. To accomplish this, the whole (“holos” in Greek) optical information emanating from a source needs to be written (“graphein” in Greek), recorded or captured on a sensing device for later recreation or reconstruction of the original object. This is the technique we now know as holography.
Ulf Schnars, Claas Falldorf, John Watson, Werner Jüptner

Chapter 2. Fundamental Principles of Holography

Abstract
The behaviour of light can be modelled either as a propagating electromagnetic (e-m) wave or as a stream of massless particles known as photons. Although the models are seemingly contradictory both are necessary to fully describe the full gamut of light phenomena. Whichever model is most appropriate depends on the phenomenon to be described or the experiment under investigation. For example, interaction of light with the atomic structure of matter is best described by the photon model: the theory of photon behaviour and its interactions is known as quantum optics. The phenomenon of refraction, diffraction and interference, however, are best described in terms of the wave model i.e. classical electromagnetism.
Ulf Schnars, Claas Falldorf, John Watson, Werner Jüptner

Chapter 3. Digital Holography

Abstract
The concept of digital holographic recording is illustrated in Fig. 3.1a (Schnars, 1994; Schnars and Jüptner, Appl Opt 33:179–181, 1994). A plane reference wave and the wave reflected from the object interfere at the surface of an electronic sensor array (e.g. Charged Coupled Device CCD, or Complementary Metal Oxide Semiconductor CMOS). The resulting hologram is electronically recorded and stored in a computer. The object is, in general, a three dimensional body with diffusely reflecting surfaces, located at a distance d from the sensor (measured to some representative plane). This is just the classical off-axis geometry of photographic holography save that the recording medium is an electronic sensor array rather than photographic film.
Ulf Schnars, Claas Falldorf, John Watson, Werner Jüptner

Chapter 4. Digital Holographic Interferometry (DHI)

Abstract
As we saw in Chap. 2, a conventional holographic interferogram recorded on photographic film is generated by superposition of two waves, which are scattered from an object in two different states of loading or excitation.
Ulf Schnars, Claas Falldorf, John Watson, Werner Jüptner

Chapter 5. Digital Holographic Particle Sizing and Microscopy

Abstract
While much of this book concentrates on the use of digital holography for vibration and stress analysis, contouring and metrology, the emphasis in this chapter is on the unique image forming characteristics of the hologram.
Ulf Schnars, Claas Falldorf, John Watson, Werner Jüptner

Chapter 6. Special Techniques

Abstract
Holographic recording of Light-in-Flight (LiF) was first proposed by Abramson (Appl Opt 22:215–232, 1983, [1], Appl Opt 23:1481–1492, 1984, [2], Appl Opt 23:4007–4014, 1984, [3], Appl Opt 24:3323–3329, 1985, [4]). He pointed out that a hologram can only image the distances in space where the optical path of the reference wave matches that of the object wave.
Ulf Schnars, Claas Falldorf, John Watson, Werner Jüptner

Chapter 7. Computational Wavefield Sensing

Abstract
With the advent of faster computer processors, alternative methods of wavefield sensing have been developed throughout the past decades. In contrast to standard interferometry, these methods aim at solving an inverse problem, whereby the recorded intensities are interpreted as an effect caused by the underlying (unknown) wavefield when subjected to different manipulations. In contrast to holography and interferometry it is not possible to use film as a recording material and to optically reconstruct the wavefield. In fact, it is even pertinent to say that the numerical task of solving the inverse problem is an essential and integral part of the measurement process.
Ulf Schnars, Claas Falldorf, John Watson, Werner Jüptner

Chapter 8. Speckle Metrology

Abstract
Electronic Speckle Pattern Interferometry (ESPI) is a method, similar HI, to measure optical path changes caused by deformation of opaque bodies or refractive index variations within transparent media (Helmers et al. in Proceedings of 4th international workshop on automatic processing of fringe patterns. Elsevier, New York, pp 673–679, 2001,[82], Lokberg, Phys Techn 11:16-22, 1980, [147]).
Ulf Schnars, Claas Falldorf, John Watson, Werner Jüptner

Backmatter

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