On the influence of the thickness of air-space on total reflection of electric radiation

1898 ◽  
Vol 62 (379-387) ◽  
pp. 300-310 ◽  
Keyword(s):  
Critical Angle ◽  
Total Reflection ◽  
Index Of Refraction ◽  
Angle Of Incidence ◽  
Minimum Thickness ◽  
Light Waves ◽  
Air Space ◽  
Air Film ◽  
The Given

In my preliminary experiments on the determination of the index of refraction of various substances for electric radiation, I used a single serai-cylinder of the given substance; the electric ray was refracted from the denser medium into air, and at the critical angle of incidence it underwent total reflection. The experiment was repeated with two semi-cylinders separated by a parallel air-space. With light waves an extremely thin air-film is effective in producing total reflection. But a question might arise whether waves a hundred thousand times as long would be totally reflected by films of air, and, if so, it would be interesting to find out the minimum thickness of air-space which would be effective in producing this result.

scholarly journals On the determination of the indices of refraction of various substances for the electric ray. II. Index of refraction of glass

1898 ◽  
Vol 62 (379-387) ◽  
pp. 293-300 ◽  
Keyword(s):  
Royal Society ◽  
Critical Angle ◽  
Total Reflection ◽  
Index Of Refraction ◽  
Angle Of Incidence ◽  
Air Space ◽  
The Given

In my previous paper, read before the Royal Society on October 20, 1895, I described a method of determining the indices of refraction of various substances for electric radiation, the principle of which depends on the determination of the critical angle at which total reflection takes place. A semi-cylinder of the given substance was taken, and the angle of incidence gradually increased till the rays were totally reflected. The experiment was repeated with two semi-cylinders, separated by a parallel air-space.

The use of a slit in determining refractive indices with the microscope

1917 ◽  
Vol 18 (84) ◽  
pp. 130-132
Author(s):  
John William Evans
Keyword(s):  
Crystal Structure ◽  
Refractive Index ◽  
Optical Properties ◽  
Critical Angle ◽  
Total Reflection ◽  
Index Of Refraction ◽  
Refractive Indices ◽  
Object Image ◽  
Ordinary Object

Certain optical properties of crystals, and more particularly the refractive index, may be determined either in the directions-image, often referred to as the 'image in convergent light', or in the ordinary object-image in which the object itself is seen. In the former case, in which the index of refraction is 'usually determined by means of the critical angle of total-reflection, every point in the image corresponds to a single direction of propagation of the wave-front through the crystal-structure and to the two corresponding directions of vibration. One of these can, however, be eliminated by the insertion of a nicol in an approximate position, and thus all ambiguity in the determination of the refractive index is removed.

Subsurface Layer Studies by Attenuated Total Reflection Fourier Transform Spectroscopy

1977 ◽  
Vol 31 (4) ◽  
pp. 289-292 ◽  
Author(s):  
Tomas Hirschfeld
Keyword(s):  
Fourier Transform ◽  
Critical Angle ◽  
Subsurface Layer ◽  
Total Reflection ◽  
Attenuated Total Reflection ◽  
Data Sets ◽  
Angle Of Incidence ◽  
Reflection Spectra ◽  
Reflection Spectroscopy ◽  
A New Technique

In total reflection spectroscopy the effective sampled depth increases as the angle of incidence approaches the critical one. At each angle of incidence, successive layers within the sample are weighed differently in the overall spectrum, and the manner of this weighing changes with angle. It is thus possible in principle to deconvolute a set of spectra taken at different angles into spectra corresponding to successive depth invervals. As this angular effect is particularly marked near the critical angle, where attenuated total reflection spectra are severely distorted, the spectra usually require inversion into optical constant spectra. This has been done by a new technique that measures spectra twice at each angle with different prism materials to give the necessary data sets. Examples of such subsurface spectra are shown.

Interferences with a Plane Parallel Plate Near the Critical Angle of Total Reflection

1985 ◽  
Vol 40 (7) ◽  
pp. 748-751
Author(s):  
K. Eidner ◽  
G. Mayer ◽  
R. Schuster
Keyword(s):  
Parallel Plate ◽  
Critical Angle ◽  
Practical Importance ◽  
Total Reflection ◽  
Angle Of Incidence ◽  
Plane Parallel ◽  
Plane Parallel Plate

The fringes of equal inclination with a plane parallel plate surrounded by an optically denser medium start at an angle of incidence less than the critical angle of total reflection. Despite its practical importance this effect was disregarded in optics up to now.

scholarly journals Analysing the Critical Orientation of Seismic Loading in 3D Buildings: Preliminary Results for Constant Lateral Forces

2018 ◽  
Vol 2 (3) ◽  
pp. 2-15 ◽  
Author(s):  
Despoina Skoulidou ◽  
Xavier Romão
Keyword(s):  
Critical Angle ◽  
Structural Characteristics ◽  
Seismic Loading ◽  
Seismic Excitation ◽  
Elastic Behaviour ◽  
Angle Of Incidence ◽  
Linear Elastic ◽  
Lateral Forces ◽  
Linear Elastic Behaviour

The angle of seismic excitation has been proven to be an important factor when analysing the 3D behaviour of buildings. However, modern earthquake-related standards only cover partially the effects of this factor and practicable results of relevant studies are still limited. The proposed paper focuses on the determination of the critical angle of incidence based on the building's structural characteristics. An analytical expression is developed to define the critical angle for the case of single storey buildings and a special category of multi storey buildings under constant lateral forces assuming linear elastic behaviour of the structures.

Ellipsometric inline inspection of dielectric substrates with nonplanar surfaces

2020 ◽  
Vol 87 (6) ◽  
pp. 383-391 ◽  
Author(s):  
Matthias Hartrumpf ◽  
Chia-Wei Chen ◽  
Thomas Längle ◽  
Jürgen Beyerer
Keyword(s):  
Index Of Refraction ◽  
Special Importance ◽  
Angle Of Incidence ◽  
Surface Geometry ◽  
Adjustment Procedure ◽  
Dielectric Substrates ◽  
State Of Polarization ◽  
Freeform Optics ◽  
Test Objects

AbstractAn analytical solution for the determination of either angle of incidence (AOI) and the refractive index from combined ellipsometric and reflectometric measurements at dielectric substrates is presented. The solution is of special importance for retroreflex ellipsometry (but not limited to this application). Overcoming the geometric restrictions of conventional ellipsometers, the patented retroreflex ellipsometry can detect changes of intensity and the state of polarization in or at test objects even with curved surfaces. In contrast to conventional ellipsometers where the AOI is set by the adjustment procedure, the AOI is usually unknown in retroreflex ellipsometry. For quantitative analysis, the knowledge of the AOI is nevertheless essential. The proposed combination of retroreflex-reflectometry and retroreflex-ellipsometry opens the path to precise measurements of either surface geometry and index of refraction of nonplanar dielectric substrates (e. g. surfaces of freeform optics).

A diagram for use with the total-reflectometer

1912 ◽  
Vol 16 (75) ◽  
pp. 236-238 ◽  
Author(s):  
A. Hutchinson
Keyword(s):  
Refractive Index ◽  
Critical Angle ◽  
Graphical Method ◽  
Plane Surface ◽  
Monochromatic Light ◽  
Total Reflection ◽  
Plate Viii

The accompanying diagram (Plate VIII) has been prepared in order to facilitate the determination of indices of refraction with the Kohlrausch total-reflectometer, by affording a means of rapidly werking out the results by a graphical method.The Kohlrausch instrument enables measurements to be made of the critical angle θ, at which total reflection begins, when monochromatic light is reflected at the plane surface of a solid of refractive index μ immersed in a liquid of higher refractive index μ′.

Determination of Heavy Metals in Environmental Water by Total Reflection X-Ray Fluorescence Method using Optimized Roentgen Optics Cut-Off Filter

1991 ◽  
Vol 35 (B) ◽  
pp. 959-963 ◽  
Author(s):  
A. I. Egorov ◽  
L. P. Kablna ◽  
I. A. Kondurov ◽  
E. M. Korotkikh ◽  
V. V. Martynov ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Critical Angle ◽  
Environmental Water ◽  
Total Reflection ◽  
Angular Deviation ◽  
Narrow Beam ◽  
X Ray ◽  
Order Of Magnitude ◽  
Elemental Contents

The total reflection x-ray fluorescence (TXRF) method of analyzing elemental contents Is based on the small angle irradiation of thin samples placed on a total reflecting backing with a narrow photon beam. Two instrumental problems are to be solved here. The first is to form the narrow beam with a small angular deviation. The usual way to solve this problem is to use collimators with small solid angles. These angles must be less than the critical angle for x-ray total reflection, which, in the energy range 10 - 20 keV has an order of magnitude around 10−3 rad.

scholarly journals Total reflection X-ray fluorescence

2019 ◽  
Vol 4 (7) ◽  
Author(s):  
Martina Schmeling
Keyword(s):  
Thin Layer ◽  
Trace Analysis ◽  
Critical Angle ◽  
Incident Angle ◽  
Biological Tissues ◽  
Total Reflection ◽  
Angle Of Incidence ◽  
X Ray ◽  
Flat Substrate ◽  
Layer Analysis

Abstract Total reflection X-ray fluorescence (TXRF) spectrometry is a non-destructive and surface sensitive multi-element analytical method based on energy dispersive X-ray fluorescence spectrometry with detection limits in the lower picogram range. It utilizes the total reflection of the primary X-ray beam at or below the critical angle of incidence. At this angle, the fluorescence intensity is substantially enhanced for samples present as small granular residue or as thin homogenous layer deposited at the surface of a thick substrate. Generally, two types of application exist: micro- and trace-analysis as well as surface and thin-layer analysis. For micro- and trace-analysis, a small amount of the solid or liquid sample is deposited on an optically flat substrate, typically quartz or polycarbonate. The dried residue is analyzed at a fixed angle setting slightly below the critical angle. Quantification is carried out by means of internal standardization. For surface and thin-layer analysis, the surface of an optically flat substrate is scanned. Variations of the incident angle of the primary X-ray beam provide information about the type and sometimes also the amount of material present at or slightly below the surface of the substrate. Major fields of application are environmental samples, biological tissues, objects of cultural heritage, semiconductors and thin-layered materials and films.

Characterisation of Interfaces in SiGe Superlatrlces by Combined Grazing Incidence X-Ray Fluorescence and Reflectivity

1991 ◽  
Vol 238 ◽  
Author(s):  
Adrian R. Powell ◽  
Jaroslav Bradler ◽  
Charles R. Thomas ◽  
Richard A. Kubiak ◽  
D. Keith Bowen ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Silicon Germanium ◽  
Critical Angle ◽  
Grazing Angle ◽  
Single Layer ◽  
High Sensitivity ◽  
Grazing Incidence ◽  
Total Reflection ◽  
X Ray

ABSTRACTX-Ray reflectivity enables the determination of interface and surface roughness along with the variations present in the electron density. Total reflection X-ray fluorescence allows surface analysis with high sensitivity and quantification. By use of grazing angle x-ray fluorescence taken simultaneously with the reflectivity measurements, over a range of angles near the critical angle, it is possible in principle to produce a depth profile of each element, with a composition sensitivity of 0.0002%. A silicon-germanium single layer was used to calibrate the instrument and a Si-Ge 5- period superlattice for a demonstration measurement.

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