Calculations on lens systems are often marred by the unjustifiable use of the small-angle approximation. This book describes in detail how the ray and wave pictures of lens behaviour can be combined and developed into a theory capable of dealing with the large angles encountered in real optical systems. A distinct advantage of this approach is that Fourier optics appears naturally, in a form valid for arbitrarily large angles. The book begins with extensive reviews of geometrical optiks, eikonal functions and the theory of wave propagation. The propagation of waves through lenses is then treated by exploiting the close connection between eikonal function theory and the stationary phase approximation. Aberrations are then discussed, and the book concludes with various applications in lens design and analysis, including chapters on laser beam propagation and diffractive optical elements. Throughout, special emphasis is placed on the intrinsic limitations of lens performance. The many practical insights it contains, as well as the exercises with their solutions, will be of interest to graduate students as well as to anyone working in optical design and engineering.

This book describes techniques used to predict the quality of images formed by optical systems, such as telescopes, camera lenses, and microscope objectives. It covers in detail how the ray and wave pictures of lens behavior can be combined and developed to produce a theory capable of dealing with the large angles encountered in real optical systems. Several applications are considered, including the propagation of a Gaussian beam along a skew ray, a clear and convincing demonstration that diffractive optical elements are subject to the same fundamental limitation as conventional lenses, a thorough discussion of the "cosine-to-the-fourth law," and a detailed example of mock ray tracing. Containing many practical insights, as well as exercises and solutions, this book will be of great interest to graduate students taking courses in this field, and to anyone working in optical design and engineering.

"the immediate excess poems" contains the prerequiisite 'streams of consciousness' and abstractness usually considered in art or poems. This volume also combines a straightforward style of 'story-poem' the author (partial pen name a. walther) uses to describe the, sometimes, very simple steps to finding life in art and vice versa. Whether critical or prasing the views and "excesses" in these poems range from tv, movies, music, jazz, and, of course, politics and religion. In art (the poem) should never look to conform to convention.

Far from being solely a terrorist organization, Hamas is a heterogeneous movement which has situational awareness and uses violence or political participation after a cost-benefit analysis. Hamas' main objective is to stay in power and preserve its identity. Hamas is unlikely to publicly reject its ideology. Two opinions about Hamas are prevalent. On the one hand Hamas is assessed as a radical terrorist organization. The policy implication of this first opinion is simple: Hamas cannot be reformed and will continue to use violence. Therefore, Hamas must be neutralized. On the other hand, Hamas is assessed as a social movement which does not necessarily need to use violence. This school of thoughts assesses Hamas as a movement that can learn to refrain from violence. The policy implication of this position is that Hamas' inclusion in politics supports the process of moderation of Hamas into a non-violent organization. Both policies either proved to be ineffective or imply risks. This thesis asserts a middle position. Hamas' decisions to act depend on two factors. First, its internal situation is of importance. Second, and even more important, the political and situational circumstances on the ground in Palestine have a strong impact on Hamas. The middle position implies that the situation on the ground can be influenced in a way that may give Hamas little or no incentive to use violence.