The tandem component is a holographic component which permits generation of a general complex wave front with 100% light efficiency. It consists of two phase-only elements in two Fourier conjugate planes and of a lens...
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The tandem component is a holographic component which permits generation of a general complex wave front with 100% light efficiency. It consists of two phase-only elements in two Fourier conjugate planes and of a lens. Applications of this component are discussed such as complex wave front reconstruction, beam shaping, and correlation type measurements.
A propagator model using Feynman diagrams is presented for studying the first and the second moments of the electromagnetic field in a discrete random medium. The major difference between our work and previous treatme...
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A propagator model using Feynman diagrams is presented for studying the first and the second moments of the electromagnetic field in a discrete random medium. The major difference between our work and previous treatments of this type is that all diagrams are in a basis of vector spherical functions. Each propagator or infinite-medium Green’s function is the translation matrix for spherical functions, and each scatterer is characterized by a T matrix that, in turn, is a representation of the Green’s function of the scatterer in a basis of spherical functions. All orders of multipoles are formally retained, in contrast to previous work involving the dipole approximation. Partial resummations of the scattering diagrams are shown to be related to the quasi-crystalline approximation and the first-order smoothing approximation. The lowest-order term of the ladder approximation for the incoherent intensity is evaluated. Sample numerical results are presented and compared with available experimental results.
First, from the viewpoint of mathematical transformation, the restoring equation is derived. Then, from the physical viewpoint, the operation equation and the space calibration equation of the satellite-borne spectrom...
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First, from the viewpoint of mathematical transformation, the restoring equation is derived. Then, from the physical viewpoint, the operation equation and the space calibration equation of the satellite-borne spectrometer are established. Using these three equations, the inaccurately measured data provided by the IR spectrometer after performance degradation of some of its parts can be restored to the accurate values it possessed during ground calibration, and its service life (e.g., over ten years) can be discussed. Finally, as an example, a restoration method for these conditions is given in which the optical system is wholly normal and the blackbody performance is degraded.
Starting with an expansion of a pupil function into azimuthal Fourier harmonics, a general formula that represents the point-spread function as a weighted sum of successive Hankel transforms is derived. The correspond...
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Starting with an expansion of a pupil function into azimuthal Fourier harmonics, a general formula that represents the point-spread function as a weighted sum of successive Hankel transforms is derived. The corresponding transforms can rapidly be computed by using the quasi-fast Hankel transform algorithm. The method appears to be far more useful than purely digital two-dimensional fast-Fourier-transform techniques, especially for symmetrical systems.
A new method for solving the phase problem in two dimensions is presented. The solution is noniterative and is based on locating the zeros of one-dimensional strips of a single two-dimensional intensity distribution. ...
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A new method for solving the phase problem in two dimensions is presented. The solution is noniterative and is based on locating the zeros of one-dimensional strips of a single two-dimensional intensity distribution. A numerical example is included.
In keeping with the recent growth of interest in the use of analytic computational methods in the analysis of the behavior of optical systems, this paper reports on the incorporation of chromatic dependence into these...
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In keeping with the recent growth of interest in the use of analytic computational methods in the analysis of the behavior of optical systems, this paper reports on the incorporation of chromatic dependence into these schemes. A novel prescription for the truncation of power series in several variables (which is also of value outside this context) is introduced in order to avoid much unnecessary computation. Subsequently, a process is devised for computing chromatic aberration coefficients to arbitrary orders for symmetric systems composed of homogeneous lenses and mirrors. It is found that, in less than the time required for the analytical analysis of a system at two distinct wavelengths, this process can yield the required results for the entire visible spectrum and beyond, if necessary.
Various analytical or diagnostic techniques (e.g., evaluation of 2-D electrophoretograms, discrimination, and counting of objects) deal with pictures containing many similar patterns or objects and a few which are dis...
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Various analytical or diagnostic techniques (e.g., evaluation of 2-D electrophoretograms, discrimination, and counting of objects) deal with pictures containing many similar patterns or objects and a few which are dissimilar. In this paper an efficient method is described which analyzes such pictures. It proceeds in three stages: removal of film background, separation into regions enclosing a single object or pattern, and classification of these regions into groups containing objects that are similar. The classification is based on moment analysis of the separated regions. The limitations due to noise (film granularity and fluctuations in object shape) on the selection of moment orders are discussed. Using selected integral functions (moments) and a corresponding choice of variables for the representation of 2-D space, adapted to the particular characteristics of the patterns to be classified, leads to a fast method for discriminating patterns that are difficult to distinguish by visual inspection because of their low texture content. The intended application of the method is automated data extraction from 2-D electrophoretograms. The performance of the procedure is shown in two examples.
Four numerical methods useful for determining the band parameters of infrared transmittance models are presented. A double exponential function described by three absorber parameters and one spectral parameter is adop...
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Four numerical methods useful for determining the band parameters of infrared transmittance models are presented. A double exponential function described by three absorber parameters and one spectral parameter is adopted as the transmittance model. The methods are compared for accuracy and convenience through an application to line-by-line and measured data for nitrous oxide (N 2 O) of 20-cm −1 resolution over a wide range of atmospheric conditions. Sufficient mathematical details are provided so that the methods may be easily adapted to other transmittance functions. One of these—the weighted average method—is shown to be clearly superior to the others.
The implementation of an all-optical scanning function utilizing twin-stripe injection lasers is discussed. Calculation are performed for 3- μ m wide stripe devices allowing for stripe separations of 1 and 3 μ m. Th...
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The implementation of an all-optical scanning function utilizing twin-stripe injection lasers is discussed. Calculation are performed for 3- μ m wide stripe devices allowing for stripe separations of 1 and 3 μ m. The effect of optical injection under one of the stripes is computed for different injection currents. It is shown that the change in the gain profile brought about by optical injection leads to a rotation in the device far field. The merits of electronic and optical beam steering are briefly compared.
Toric unstable resonators consisting of two annular mirrors of toroidal shape are analyzed using geometrical, diffractive, and asymptotic theory. Geometrical modes and eigenvalues are derived using nonuniform magnific...
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Toric unstable resonators consisting of two annular mirrors of toroidal shape are analyzed using geometrical, diffractive, and asymptotic theory. Geometrical modes and eigenvalues are derived using nonuniform magnification theory. The eigenvalues are identical to those for strip resonators, while the mode intensities include a 1/ r dependence. Diffractive modes and eigenvalues exhibit some of the geometrical properties and show that toric resonators have little azimuthal mode separation. First-order asymptotic theory shows that high spatial frequency oscillations in the diffractive modes are due to inner and outer edge waves, with the inner edge wave dominating.
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