Energy distribution on the focal plane of a parabolic cylindrical concentrator with angular defocusings

This investigation is a continuation of a former one in which an expression was derived for a light pulse with an energy distribution given by Wien's law. The first three paragraphs are supplementary to the former paper; the rest of the investigation deals with the passage of the same pulse through a prism and its separation into the different colours in the focal plane of a telescope. The general principles according to which this must take place are, of course, known, but here the actual disturbance at every point in the focal plane is given for the first time as a definite function of the time and as a result it is possible to state how many waves there are in the trains, which the single initial pulse gives rise to in the various parts of the spectrum. §1. My general expression for the initial form of a light pulse was cos ( n + ½) θ /( x 2 + h 2 ) (2 n +1)/4 , where tan θ = x/h . I did no notice until after the former paper was communicated, that this expression is 1/Г ( n + ½) ∫ ∞ 0 e - ha cos αx α n -½ dα .

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Numerical Simulation for Focal Region Characterization in a New Solar Concentrator

International Journal of Nanoscience ◽

10.1142/s0219581x14600060 ◽

2014 ◽

Vol 13 (05n06) ◽

pp. 1460006

Author(s):

Leilei Wang

Keyword(s):

Energy Distribution ◽

Focal Plane ◽

Focal Spot ◽

Specular Reflection ◽

Position Error ◽

Focal Region ◽

Solar Concentrator ◽

Absolute Value ◽

Pointing Error ◽

New Type

Considering the sun light nonparallelism, Monte Carlo ray tracing method and specular reflection law are employed to simulate the effects of focal plane position error, pointing error to spot shape and energy distribution on focal plane of a new type of space solar concentrator. The results show that: with the absolute value of focal plane position error increasing, focal spot radius increases and peak energy flux value on focal plane decreases; when absolute value of focal plane position error is same, focal spot shape and energy distribution is almost the same; with pointing error increasing, the deviation of focal spot from the focal plane center increases and round focal spot becomes oval focal spot gradually. This will provide a reference for the new space solar concentrating and absorbing system design.

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Effect of the fill factor of an annular diffraction grating on the energy distribution in the focal plane

Journal of Optical Technology ◽

10.1364/jot.84.000580 ◽

2017 ◽

Vol 84 (9) ◽

pp. 580 ◽

Cited By ~ 13

Author(s):

A. V. Ustinov ◽

A. P. Porfir’ev ◽

S. N. Khonina

Keyword(s):

Energy Distribution ◽

Diffraction Grating ◽

Focal Plane ◽

Fill Factor

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DETERMINATION OF THE DENSITY VALUE SPECIFICALLY AT THE FOCAL POINT OF THE MIRROR CONCENTRATING SYSTEM

Computational nanotechnology ◽

10.33693/2313-223x-2019-6-4-49-55 ◽

2019 ◽

Vol 6 (4) ◽

pp. 49-55

Author(s):

Yuldash Begzhanovich Sobirov ◽

Rustam Khakimovich Rakhimov ◽

Shakhriyor Abdujabbarovich Abdurakhmanov

Keyword(s):

Energy Distribution ◽

Focal Plane ◽

Focal Point ◽

Angular Size ◽

Analytical Calculation ◽

Radiant Flux ◽

The Sun ◽

Partial Shading ◽

Focal Zone ◽

Reflective Surfaces

When designing mirror concentrating systems, it is necessary to determine in advance the optical-geometric and optical-energy characteristics of the installation. One is required to choose the mirrors with a reflection coefficient to satisfy the expected energy distribution in the focal area and to pay attention to the accuracy of the reflective surfaces of the mirrors, to the accuracy of the tracking system of the heliostats to the trajectory of the apparent motion of the Sun, to the partial shading to the reflective surfaces, etc. Based on these data, it is necessary to calculate the irradiance distribution in the focal zone of the installation. During installation and utilization of the equipment it is necessary to measure and monitor these parameters and, if necessary, to recalculate the energy distribution taking into account the new parameters.The methods for calculating the density distribution of the radiant flux in the focal zone of mirror-concentrating systems have been developed in parallel with the requirements of exploitation. They do not always correctly reflect the true picture formed in the focus of the heliostat. In this paper, the analysis presents the existing methods for calculating paraboloid concentrators based on the Gaussian distribution of energy in the focal plane. Developing the method of fallen and reflected elementary cone beam and on the basis of generated scattered optical images of the Sun and of the visible angular size (2γо = 32 angle of minutes) of the Sun, which shows non-Gaussian nature of the resulting distribution in the focal plane due to the influence of aberration of the optical paraboloidal surface depending on the change of the aperture angle 2U, we obtained an analytical calculation formula to determine the value of the concentrated radiant flux specifically at the focal point of a paraboloid mirror concentrating system.

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Energy Distribution in Electron Beams

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100096096 ◽

1972 ◽

Vol 30 ◽

pp. 568-569

Author(s):

Tamotsu Ohno

Keyword(s):

Electron Beam ◽

Energy Distribution ◽

Cross Section ◽

Integral Curve ◽

Electron Beams ◽

Electron Gun ◽

Angular Divergence ◽

Apparent Increase ◽

Integral Width ◽

The Cross

The energy distribution in an electron; beam from an electron gun provided with a biased Wehnelt cylinder was measured by a retarding potential analyser. All the measurements were carried out with a beam of small angular divergence (<3xl0-4 rad) to eliminate the apparent increase of energy width as pointed out by Ichinokawa.The cross section of the beam from a gun with a tungsten hairpin cathode varies as shown in Fig.1a with the bias voltage Vg. The central part of the beam was analysed. An example of the integral curve as well as the energy spectrum is shown in Fig.2. The integral width of the spectrum ΔEi varies with Vg as shown in Fig.1b The width ΔEi is smaller than the Maxwellian width near the cut-off. As |Vg| is decreased, ΔEi increases beyond the Maxwellian width, reaches a maximum and then decreases. Note that the cross section of the beam enlarges with decreasing |Vg|.

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Tandem scanning reflected light microscopy: How it works and applications

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142104 ◽

1986 ◽

Vol 44 ◽

pp. 84-87

Author(s):

Alan Boyde ◽

Milan Hadravský ◽

Mojmír Petran ◽

Timothy F. Watson ◽

Sheila J. Jones ◽

...

Keyword(s):

Light Microscopy ◽

Focal Plane ◽

Central Symmetry ◽

Single Line ◽

Scanning Microscope ◽

Reflected Light ◽

Illuminating Light ◽

Illuminating Beam

The principles of tandem scanning reflected light microscopy and the design of recent instruments are fully described elsewhere and here only briefly. The illuminating light is intercepted by a rotating aperture disc which lies in the intermediate focal plane of a standard LM objective. This device provides an array of separate scanning beams which light up corresponding patches in the plane of focus more intensely than out of focus layers. Reflected light from these patches is imaged on to a matching array of apertures on the opposite side of the same aperture disc and which are scanning in the focal plane of the eyepiece. An arrangement of mirrors converts the central symmetry of the disc into congruency, so that the array of apertures which chop the illuminating beam is identical with the array on the observation side. Thus both illumination and “detection” are scanned in tandem, giving rise to the name Tandem Scanning Microscope (TSM). The apertures are arranged on Archimedean spirals: each opposed pair scans a single line in the image.

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Imaging sub-micron objects with light microscopy: Visualization of the T-4 bacteriophage

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100156158 ◽

1989 ◽

Vol 47 ◽

pp. 834-835

Author(s):

Malcolm Brown ◽

Reynolds M. Delgado ◽

Michael J. Fink

Keyword(s):

Electron Microscopy ◽

Light Microscopy ◽

Focal Plane ◽

Phase Contrast ◽

Dark Field ◽

E Coli ◽

Polystyrene Beads ◽

Television Camera ◽

Transmission Electron ◽

Universal Microscope

While light microscopy has been used to image sub-micron objects, numerous problems with diffraction-limitations often preclude extraction of useful information. Using conventional dark-field and phase contrast light microscopy coupled with image processing, we have studied the following objects: (a) polystyrene beads (88nm, 264nm, and 557mn); (b) frustules of the diatom, Pleurosigma angulatum, and the T-4 bacteriophage attached to its host, E. coli or free in the medium. Equivalent images of the same areas of polystyrene beads and T-4 bacteriophages were produced using transmission electron microscopy.For light microscopy, we used a Zeiss universal microscope. For phase contrast observations a 100X Neofluar objective (N.A.=1.3) was applied. With dark-field, a 100X planachromat objective (N.A.=1.25) in combination with an ultra-condenser (N.A.=1.25) was employed. An intermediate magnifier (Optivar) was available to conveniently give magnification settings of 1.25, 1.6, and 2.0. The image was projected onto the back focal plane of a film or television camera with a Carl Zeiss Jena 18X Compens ocular.

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Microspectroscopy Using a Solid Immersion Lens

Microscopy and Microanalysis ◽

10.1017/s1431927600026817 ◽

2001 ◽

Vol 7 (S2) ◽

pp. 148-149

Author(s):

C.D. Poweleit ◽

J Menéndez

Keyword(s):

Spatial Resolution ◽

Focal Plane ◽

Numerical Aperture ◽

Normal Incidence ◽

Spot Size ◽

Index Of Refraction ◽

Objective Lens ◽

Improvement Factor ◽

Oil Immersion ◽

Long Time

Oil immersion lenses have been used in optical microscopy for a long time. The light’s wavelength is decreased by the oil’s index of refraction n and this reduces the minimum spot size. Additionally, the oil medium allows a larger collection angle, thereby increasing the numerical aperture. The SIL is based on the same principle, but offers more flexibility because the higher index material is solid. in particular, SILs can be deployed in cryogenic environments. Using a hemispherical glass the spatial resolution is improved by a factor n with respect to the resolution obtained with the microscope’s objective lens alone. The improvement factor is equal to n2 for truncated spheres.As shown in Fig. 1, the hemisphere SIL is in contact with the sample and does not affect the position of the focal plane. The focused rays from the objective strike the lens at normal incidence, so that no refraction takes place.

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