Showing papers in "Progress in Optics in 1984"

I Rigorous Vector Theories of Diffraction Gratings

Abstract: Publisher Summary This chapter describes the rigorous vector theories of diffraction gratings. The diffraction grating is a valuable instrument for scientific research. It is mainly used for spectroscopy and filtering. Even though the holographic grating has not eliminated the classical, ruled grating, which remains the most suitable for important applications, it has permitted a considerable extension of the use of gratings for industrial or scientific purposes such as wavelength selectors for tunable lasers, selective surfaces for solar energy, masks for photolithography, beam sampling mirrors for high power lasers, spectrometers in extreme ultraviolet (UV) or x-ray regions for Space Optics. In addition, one can consider that rigorous vector theories of gratings are able to solve almost all the classical problems of gratings encountered by manufacturers and users.

III The Radon Transform and Its Applications

Abstract: Publisher Summary This chapter discusses the Radon transform, its applications, present state of knowledge about the Radon transform, and some of its lesser-known applications. Although x-ray projections and tomographic reconstruction are used in the chapter as a starting point, no consideration is given to such things as fan-beam geometries, iterative reconstruction algorithms, polyenergetic X-rays, detector noise, or clinical applications. It is undoubtedly medical computed tomography (CT) that has attracted more attention than any other application of the Radon transform. The basic data obtained in a CT procedure are x-ray transmission measurements through a two-dimensional (2D) slice of the patient's body. Because of the overwhelming clinical and commercial success of CT, the 2D Radon transform is studied in exhaustive detail.

V Fluctuations, Instabilities and Chaos in the Laser-Driven Nonlinear Ring Cavity

Abstract: Publisher Summary This chapter explains fluctuations, instabilities, and chaos in the laser-driven nonlinear ring cavity The laser-like systems of modern optics exhibit many of these properties in an especially uncluttered setting, where their essential features are not hidden by irrelevant complexity This fact, has gained prominence with the recent appearance of new theoretical results for several such systems Among these are the driven nonlinear cavity and the laser with saturable absorber, which exhibit hysteresis and other properties analogous to those of first-order phase transitions In particular, the ring cavity with a nonlinear medium shows the universal approach to chaotic behavior as a mechanism for optical chaos The chapter presents the stationary response of the nonlinear ring cavity to an injected field utilizing the Maxwell–Bloch equations for a medium of two-level atoms In addition, the chapter discusses time-dependent behavior of the nonlinear ring cavity It describes the deterministic switching in the bistable region utilizing the Maxwell–Bloch equations Further, the chapter explains the sequence of instabilities present in the nonlinear ring cavity with fast transverse relaxation

IV Zone Plate Coded Imaging: Theory and Applications

Abstract: Publisher Summary This chapter discusses the theory and applications of zone plate coded imaging and presents comprehensive mathematical framework for a specific coded imaging (CI) technique, zone plate coded imaging (ZPCI), in which the coded aperture is a Fresnel zone plate and the image decoding method is coherent optical reconstruction. The chapter also discusses the applications of zone plate coded imaging in laser fusion experiments. As coded apertures offer a significant improvement in radiation collection over pinhole optics of equivalent resolution, and as laser fusion targets are small, ZPCI is particularly well-suited for imaging low level x-ray and particle emissions from these experiments. In addition, a compilation of ZPCI data is presented in the chapter, including 3.5 MeV alpha particle images of the region of thermonuclear burn and multispectral x-rays images covering the spectral range from 3–30 keV.