Showing papers in "Progress in Optics in 1981"
TL;DR: In this article, the authors discuss the effects of atmospheric turbulence in optical astronomy, summarizes the present state of the theory, reviews the experimental checks that have been made, and discusses the implications in the domain of astronomical observations.
Abstract: Publisher Summary This chapter discusses the effects of atmospheric turbulence in optical astronomy, summarizes the present state of the theory, reviews the experimental checks that have been made, and discusses the implications in the domain of astronomical observations. Diffraction limited resolution has been obtained with large telescopes up to magnitude 13 by means of speckle interferometry. A Michelson interferometer is already working in the visible on a 20 m baseline up to magnitude 4, and many projects are nearing completion. However, such technological progress can be useful only if accurate quantitative measurements prove to be feasible through atmospheric turbulence. In addition, much work remains to be done before achieving a full understanding of atmospheric effects. The relationship between isoplanicity or speckle boiling and the structure of the atmosphere is still not clear.
932 citations
TL;DR: The chapter reviews the coherent behavior of shift-invariant systems, and a spectral analysis of incoherent illumination is developed with special emphasis on low-pass filtering.
Abstract: Publisher Summary This chapter discusses the principles of optical data-processing. An optical system has been hitherto described in wave-theoretical terms only. The chapter reviews the coherent behavior of shift-invariant systems. In the further course, a spectral analysis of incoherent illumination is developed with special emphasis on low-pass filtering. On account of their practical usefulness, the shift-invariant systems deserve special consideration. Only shift-invariant systems handle all portions of the spatial input signal in an equal manner, thus making possible numerous types of signal processing such as low-pass, high-pass, band-pass and band-suppressing filtering, spatial differentiation, contrast improvement, phase-contrast methods, matched filtering, pattern multiplication, and image deblurring. In contrast with their shift-variant counterparts, such systems are also amenable to a strikingly simple realization.
12 citations
TL;DR: In this paper, the authors introduce the theory of intensity dependent resonance light scattering and resonance fluorescence, and describe the incident field and the scattered or emitted field in fully quantum mechanical terms to describe the problem of multiphoton scattering theory.
Abstract: Publisher Summary This chapter introduces to the theory of intensity dependent resonance light scattering and resonance fluorescence. It is necessary to describe the incident field and the scattered or emitted field in fully quantum mechanical terms to describe the problem of multiphoton scattering theory. A common way of approaching this problem is to choose a finite quantization volume and take all of the discrete modes to be initially unpopulated except the single mode that represents the incident field, which is chosen initially to have a definite number of photons in it. To treat the electromagnetic field in single-atom scattering problem, it is required to describe it entirely in terms of the correlation functions, which represent the expectation values of normally ordered products of field operators at specified points in space and time.
11 citations
TL;DR: In this article, the surface and size effects on the light scattering spectra of solids and recent developments are discussed, with emphasis on certain theoretical methods that have proved useful to those engaged in research in the area.
Abstract: Publisher Summary This chapter discusses the surface and size effects on the light scattering spectra of solids and recent developments, with emphasis on certain theoretical methods that have proved useful to those engaged in research in the area. The chapter also describes experimental studies of size and surface effects. The development of a variety of laser sources and highly sophisticated spectrometers has enabled Raman spectroscopy to become a tool of major importance in the arsenal of the solid state physics community. Until the past few years, the light scattering method has been used primarily to study elementary excitations characteristic of the infinitely extended medium. In addition, the chapter explains that a substantial body of theoretical and experimental literature has extended these methods to the study of waves, which propagate on surfaces and along interfaces, to standing wave or guided wave modes of free standing films and films on substrates, and finally to the study of inhomogeneities or subtle features near the surface with spatial extent very much smaller than the wavelength of light.
10 citations
TL;DR: In this article, the authors describe inelastic scattering of photons by surface polaritons in various geometries and present a short review of theories on surface roughness effect and the results.
Abstract: Publisher Summary This chapter describes inelastic scattering of photons (Raman scattering) by surface polaritons in various geometries. Scattering experiments involve three particles (waves) in contrast to two in the case of absorption experiments. Thus, there is an additional degree of freedom in the interaction process, and wave-vector (momentum) conservation can be achieved easily by adjusting the angle between the directions of the incident and scattered waves (particles). The chapter reviews the theoretical and experimental aspects of the Raman scattering studies of surface electromagnetic waves. It also explains the theory of surface polaritons in various sample geometries. In addition, it presents a short review of theories on surface roughness effect and the results. This chapter concludes by presenting the remarks and prospects for the future.
8 citations