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Optical problem

The development of mote intense sources (eg, plasma sources, soft x-ray lasers, and synchrotron sources) has made possible highly effective instmments both for x-ray microscopy and x-ray diffraction on a few cubic nanometer sample. The optical problem of focusing x-rays is accompHshed by the use of zone plates or by improved grazing incidence or multilayer reflectors. [Pg.332]

It is evident from physical considerations that the Bragg conditions for diffraction will be of exactly the same kind as for X-rays. However, quantitative results require the solution of the optical problem of diffraction by a finite stack of dielectric sheets having a periodic variation of dielectric constant. This problem is best handled by numerical means and the question is discussed by Hayter et al. [53J, who also give references to earlier papers in which the numerical methods are fully discussed. Similar methods have also been made use of by Nicklow et al. [541. Further studies were made by Highfield et al. [55]. [Pg.35]

In a new graphical way, we have solved optical problems found in the literature regarding special relativity. To arrive at these results, we used the accepted concept of the constancy of the speed of light and the following tools a string and two nails for making ellipses and a ruler, pen, and paper to draw the diagrams. [Pg.286]

The question of the applicability of the semiclassic adiabatic approach to the vibronic problems in the JT systems is rather complicated in general and the thorough answer can be done with regard to a particular problem. In our brief discussion of this question we will refer to two areas - thermodynamic properties and resonance (optical) problems. In Ref. [9] the magnetic properties of mixed-valence dimeric and trimeric clusters are considered in the framework of... [Pg.426]

Laminating lends itself to the manufacture of resilient products with a large flat surface area and excellent surface properties. These products can be converted to their final form by thermoforming and insert molding. This method avoids the use of paint with its negative side effects, that is, the influence of solvents on the physical properties of the injection-molded part (tension and plasticizing effect). The lamination process also circumvents the optical problem of flow and weld lines. [Pg.218]

The appearance of Stokes publication, in which the concept of a vector representation of the beam description parameters was introduced, renders back to 1852. It, however, has remained for many years unnoticed (Shurcliff, 1962). The need for a general systematic and effective procedure for solving the exponentially growing quantity of optical problems has led to the rediscovery of Stokes approach to polarized radiation. Mueller s contribution consists of developing a matrix calculus for evaluation of the four elements of the Stokes vector which are a set of quantities describing the intensity and polarization of a light beam. [Pg.79]

M could be considered as an equivalent Mueller matrix corresponding to a hypothetical equivalent optical element which substitutes for the overall effect of E Ej, ,E . In many cases the equivalent element can really exist so that the analysis on the basis of the Stokes-Mueller method would often be able to predict the simplest solution to a given optical problem. Let us consider a few typical examples for the application of the method. [Pg.83]

Numerous arrangements have been used to visualize flow through porous media. Monolayers of beads with varying wettability were the first micromodels developed (8,10). Optical problems caused by... [Pg.262]

Kaneko has independently developed a systematic approach to the problem that is similar to that of ref. 21 and has applied his method to optical problems. [Pg.33]

Very often baseline problems are related to detector problems. Many detectors are available for HPLC systems. The most common are fixed and variable wavelength ultraviolet spectrophotometers, refractive index, and conductivity detectors. Electrochemical and fluorescence detectors are less frequently used, as they are more selective. Detector problems fall into two categories electrical and mechanical/optical. The instrument manufacturer should correct electrical problems. Mechanical or optical problems can usually be traced to the flow cell however, improvements in detector cell technology have made them more durable and easier to use. Detector-related problems include leaks, air bubbles, and cell contamination. These usually produce spikes or baseline noise on the chromatograms or decreased sensitivity. Some cells, especially those used in refractive index detectors, are sensitive to flow and pressure variations. Flow rates or backpressures that exceed the manufacturer s recommendation will break the cell window. Old or defective source lamps, as well as incorrect detector rise time, gain, or attenuation settings will reduce sensitivity and peak height. Faulty or reversed cable connections can also be the source of problems. [Pg.1658]

Around 1621, the Dutch scientist Wihibrod Snell discovered the correct law of refraction, which both Ptolemy and Alhazen were unable to deduce. By applying heuristic momentum conservation arguments in terms of sines, Rene Descartes independently derived the law in his 1637 philosophical and mathematical treatise. Discourse on Method. Descartes was able to solve several optical problems with the aid of this law. [Pg.37]

We make now, similarly as is common with the different integral transforms, a correspondence table between the stochastic variable and the associated characteristic function. Note, there are several integral transforms. The most well-known integral transformation might be the Fourier transform. Further, we emphasize the Laplace transform, the Mellin transform, and the Hilbert transform. These transformations are useful for the solution of various differential equations, in communications technology, all ranges of the frequency analysis, also for optical problems and much other more. We designate the stochastic variable with X. The associated characteristic function should be... [Pg.363]

As we shall see, this is an S-matrix of order 7.) In both the weighing and the optical problem the n measurements tell us the values of... [Pg.49]

So far we have said nothing about the conditions needed before this reduction in mean squared error can be attained. The chief requirement is that the error e in the i-th measurement (i.e., the i-th reading of the spring balance or optical detector) be independent of the quantity being measured, for i = l,2,, n. In the weighing problem this implies that the objects to be weighed should be light in comparison with the mass of the balance, and in the optical problem that the noise in the detector be independent of the... [Pg.50]

The idea of sending a PEL into space, along with its associated accelerator and undulator,and so avoiding some of the optical problems, has been proposed but is difficult to imagine as a practical solution. [Pg.143]

Palto, S.P. Algorithm for solution of optical problem for lamellar anisotropic media. Zh. Eksp. Teor Eiz. 119, 638-648 (2001) [JETP 103, 469 (2006)]... [Pg.73]

The treatment of the optical problem when anisotropic absorption is present can be carried out in the same manner as in the nonabsorbing case, except that now complex refractive indices... [Pg.176]

Application of TT to evaluate. MWD means to correctly solve two reverse problems. The first, optical problem consists in calculating a precipitation curve x - x( j) from the meausiired properties of scattered light the second, thermodynamic problem must provide a means of converting this curve x - 2(7) into the corresponding. VfWD function (7 is the volume fraction of precipitant in the system). [Pg.317]

Siciliano, Antonio. Optics Problems and Solutions. Singapore World Scientific Publishing, 2006. Geared to physics and engineering undergraduates, this text includes chapters on basic optics with problems that can be used by students to improve understanding of optical concepts. [Pg.1369]

Fogiel, M. (Ed.) (1981). The Optics Problem Solver, pp. 817. Research Education Association, New York. [Pg.27]

The theory of themulti layer optical problem of the SBSC structure has been described in the literature. For single layer dielectric coatings on silicon the optimum refractive index is 2.1 - 2.4. Coatings with refractive indices within this region lead to practically identical results with theoretical reflection losses as low at 6% for both Si and GaAs substrates. [Pg.91]

Apart from optic problems a limit to higher numerical aperture systems is set by depth of focus considerations. Whilst larger numerical apertures improve resolution, a concurrent reduction in depth of focus is seen. The depth of focus, S, as derived from the Rayleigh criterion, shows an inverse square dependence on the numerical aperture... [Pg.225]

Fig. 6 Examples of artifacts optical problem (top), oil mixing (middle) and vibrations (bottom)... Fig. 6 Examples of artifacts optical problem (top), oil mixing (middle) and vibrations (bottom)...

See other pages where Optical problem is mentioned: [Pg.338]    [Pg.239]    [Pg.224]    [Pg.1157]    [Pg.573]    [Pg.187]    [Pg.79]    [Pg.80]    [Pg.206]    [Pg.1199]    [Pg.113]    [Pg.125]    [Pg.347]    [Pg.86]    [Pg.109]    [Pg.94]    [Pg.659]    [Pg.175]    [Pg.1800]    [Pg.1802]    [Pg.1127]    [Pg.8]    [Pg.236]   
See also in sourсe #XX -- [ Pg.317 ]




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