Catálogo de publicaciones - libros

The mystery of light has formed the core of creation stories in every culture, and attracted the earnest attentions of philosophers since at least the fifth century BCE. Their questions have ranged from how and what we see, to the interaction of light with material bodies, and finally to the nature of light itself. This chapter begins with a brief intellectual history of light from ancient Greece to the end of the 19th century. After introducing the physical parameterization of light in terms of standard units, three concepts of light are introduced: light as a wave, light as a quantum particle, and light as a quantum field. After highlighting the distinctive characteristics of light beams from various sources – thermal radiation, luminescence from atoms and molecules, and synchrotron light sources – the distinctive physical characteristics of light beams are examined in some detail. The chapter concludes with a survey of the statistical and quantum-mechanical properties of light beams. In the appropriate limits, this treatment not only recovers the classical description of light waves and the semiclassical view of light as a stream of quanta, but also forms a consistent description of quantum phenomena – such as interference phenomena generated by single photons – that have no classical analogs.

This chapter shall discuss the basics and the applications of geometrical optical methods in modern optics. Geometrical optics has a long tradition and some ideas are many centuries old. Nevertheless, the invention of modern personal computers which can perform several million floating-point operations in a second also revolutionized the methods of geometrical optics and so several analytical methods lost importance whereas numerical methods such as ray tracing became very important. Therefore, the emphasis in this chapter is also on modern numerical methods such as ray tracing and some other systematic methods such as the paraxial matrix theory.

We will start with a section showing the transition from wave optics to geometrical optics and the resulting limitations of the validity of geometrical optics. Then, the paraxial matrix theory will be used to introduce the traditional parameters such as the focal length and the principal points of an imaging optical system. Also, an extension of the paraxial matrix theory to optical systems with non-centered elements will be briefly discussed. After a section about stops and pupils the next section will treat ray tracing and several extensions to analyze imaging and non-imaging optical systems. A section about aberrations of optical systems will give a more vivid insight into this matter than a systematic treatment. At the end a section about the most important optical instruments generally described with geometrical optics will be given. These are the achromatic lens, the camera, the human eye, the telescope, and the microscope.

For more information about the basics of geometrical optics we refer to text books such as [,,,,,,,].

The quest to understand the nature of light is centuries old and today there can be at least three answers to the single question of what light is depending on the experiment used to investigate lightʼs nature: (i) light consists of rays that propagate, e.g., rectilinear in homogeneous media, (ii) light is an electromagnetic wave, (iii) light consists of small portions of energy, or so-called photons. The first property will be treated in the chapter about geometrical optics, which can be interpreted as a special case of wave optics for very small wavelengths. On the other hand, the interpretation as photons is unexplainable with wave optics and, above all, contradictory to wave optics. Only the theory of quantum mechanics and quantum field theory can simultaneously explain light as photons and electromagnetic waves. The field of optics treating this subject is generally called quantum optics.

In this chapter about wave optics the electromagnetic property of light is treated and the basic equations describing all relevant electromagnetic phenomena are Maxwellʼs equations. Starting with the Maxwell equations, the wave equation and the Helmholtz equation will be derived. Here, we will try to make a tradeoff between theoretical exactness and a practical approach. For an exact analysis see, e.g., []. After this, some basic properties of light waves like polarization, interference, and diffraction will be described. The propagation of coherent scalar waves is especially important in optics. Therefore, the section about diffraction will treat several propagation methods like the method of the angular spectrum of plane waves, which can be easily implemented on a computer, or the well-known diffraction integrals of Fresnel–Kirchhoff as well as Fresnel and Fraunhofer. In modern physics and engineering, lasers are very important and therefore the propagation of a coherent laser beam is of special interest. A good approximation for a laser beam is a Hermite–Gaussian mode and the propagation of a fundamental Gaussian beam can be performed very easily if some approximations of paraxial optics are valid. The formulae for this are treated in the last section of this chapter.

This chapter provides a brief introduction into the basic nonlinear-optical phenomena and discusses some of the most significant recent advances and breakthroughs in nonlinear optics, as well as novel applications of nonlinear-optical processes and devices.

Nonlinear optics is the area of optics that studies the interaction of light with matter in the regime where the response of the material system to the applied electromagnetic field is nonlinear in the amplitude of this field. At low light intensities, typical of non-laser sources, the properties of materials remain independent of the intensity of illumination. The superposition principle holds true in this regime, and light waves can pass through materials or be reflected from boundaries and interfaces without interacting with each other. Laser sources, on the other hand, can provide sufficiently high light intensities to modify the optical properties of materials. Light waves can then interact with each other, exchanging momentum and energy, and the superposition principle is no longer valid. This interaction of light waves can result in the generation of optical fields at new frequencies, including optical harmonics of incident radiation or sum- or difference-frequency signals.

This chapter provides an extended overview on todayʼs optical materials, which are commonly used for optical components and systems. In Sect.  the underlying physical background on light–matter interaction is presented, where the phenomena of refraction (linear and nonlinear), reflection, absorption, emission and scattering are introduced. Sections through focus on the detailed properties of the most common types of optical materials, such as glass, glass ceramics, crystals, and plastics. In addition, special materials displaying “unusual nonlinear” or “quasi-nonreversible” optical behavior such as photorefractive or photorecording solids are described in Sect. . The reader could use this chapter as either a comprehensive introduction to the field of optical materials or as a reference text for the most relevant material information.

Within the scientific conception of the modern world, thin film optical coatings can be interpreted as one-dimensional photonic crystals. In general, they are composed of a sequence of single layers which consist of different transparent dielectrics with a thickness in the nanometer scale according to the operation wavelength range. The major function of these photonic structures is to adapt the properties of an optical surface to the needs of specific applications. By application of optical thin film coatings with optimized designs, the spectral characteristics of a surface can be modified to practically any required transfer function for a certain wavelength range. For example, the Fresnel reflection of a lens or a laser window can be suppressed for a broad wavelength range by depositing an antireflective coating containing only a few single layers. On the basis of a layer stack with alternating high- and low-refracting materials, high reflectance values up to 99.999% can be achieved for a certain laser wavelength. In addition to these basic functions, optical coatings can realize a broad variety of spectral filter characteristics according to even extremely sophisticated demands in modern precision optics and laser technology. Moreover, recent developments in optical thin film technology provide the means to combine selected optical properties with other features concerning, for instance, the thermal, mechanical or chemical stability of a surface. The latest progress in ophthalmic coatings even includes the integration of self-cleaning, photoactive or anti-fogging functions in antireflective coatings on glass.

As a consequence of this enormous flexibility in adjusting the properties of functional surfaces, optical coatings can be found in nearly every product and development of modern optic today.

In order to keep pace with the rapid development of optical technology, innovations in the design, deposition processes and handling of optical coatings are some of the crucial factors. Also, high demands in respect to precision and reproducibility are imposed on the control of layer thickness during the production of the coating systems. For certain applications in fs lasers or optical measurement systems the individual layer thickness has to be controlled within the sub-nanometer scale, which can be only achieved on the basis of advanced in situ monitoring techniques of the growing layers. These skills have to be complemented by extended knowledge of characterization, because optimization and marketing of optical coatings can only be performed on the basis of reliable and standardized characterization techniques. The present chapter addresses these major aspects of optical coatings and concentrates on the essential topics of optical coatings in their theoretical modeling, production processes, and quality control.

To insure that an optical system performs to specifications, the optical engineer needs to fully consider several aspects of the design process. Each of these tasks can be aided with the use of software tools. The optical engineer needs to understand the strengths and limitations of the available software tools and how to best apply these programs to each design. There are several distinct steps in the implementation of an optical system: the first order optical layout, optimized design of the optical system, performing stray, scattered and ghost analysis, performing a tolerance analysis of the optical system and performing manufacturing analysis. Although each of these steps are often considered separately, and often require the use of several different software tools, it is imperative for the engineer to consider the entire process during each phase of system development so that issues arising from stray light or manufacturing tolerances do not force a redesign of the system. A thorough understanding of the optical design and analysis process as well as the proper use of available optical software tools are necessary to insure the optimum optical design for each specific application.

This chapter describes a selection of advanced optical components including the underlying physical principles, production techniques and already existing or possible future applications.

Several of these optical elements, in particular variable lenses and photonic crystals, may replace conventional optical systems once their potential for applications has been fully explored. Other components such as high-quality optical fibres, though well established and used worldwide, still undergo a rapid further improvement and integration in communication systems.

Besides increased quality and versatility, a driving force and essential aspect in the development of optical components in general is low cost and mass production.

Optical detectors are applied in all fields of human activities – from basic research to commercial applications in communication, automotive, medical imaging, homeland security, and other fields. The processes of light interaction with matter described in other chapters of this handbook form the basis for understanding the optical detectors physics and device properties.

This chapter starts with a brief historical sketch of first experiments facilitating development of optical detectors. The overview of photo detector types is followed by the description of the most important figures of merit and different detection regimes.

A detailed description of different types of optical detectors is presented in the following sections. The device structure and physics as well as important materials for fabrication, figures of merit, and brief application notes are given for photoconductors, photodiodes, quantum well photodetectors, semiconductor detectors with intrinsic amplification, charge transfer detectors, photoemissive detectors, and thermal photodetectors. The chapter includes also a brief overview of imaging systems and principles of black and white and color photography.

Since the invention and industrialization of incandescent lamps at the end of the 19th century electrical lighting has become a commodity in our daily life. Today, incoherent light sources are used for numerous application areas. Major improvements have been achieved over the past decades with respect to lamp efficiency Fig. , lifetime and color properties.

In the following chapters an overview of various lamp types and their properties is given. They are subdivided by light generation mechanism: thermal emission of radiation close to thermal equilibrium (incandescent lamps), atomic and molecular emission in gas discharge lamps, and emission from solid-state light sources (LEDs).