Interference of direct transitions and surface emission in ARPES studied by changing the light incidence angle

2000 ◽  
Vol 62 (15) ◽  
pp. 10544-10547 ◽  
Author(s):  
T. Michalke ◽  
A. Gerlach ◽  
K. Berge ◽  
R. Matzdorf ◽  
A. Goldmann
Keyword(s):  
Incidence Angle ◽  
Surface Emission ◽  
Light Incidence Angle

Influence of the light incidence angle on the precision of generalized magneto-optical ellipsometry

2015 ◽  
Vol 386 ◽  
pp. 150-154 ◽  
Author(s):  
C. Gonzalez-Fuentes ◽  
J.B. Gonzalez-Diaz ◽  
L. Fallarino ◽  
J.A. Arregi ◽  
A. Berger
Keyword(s):  
Incidence Angle ◽  
Light Incidence Angle ◽  
Optical Ellipsometry

Destruction of Epoxy Coatings under the Influence of Climatic Factors

2013 ◽  
Vol 199 ◽  
pp. 581-586 ◽  
Author(s):  
Danuta Kotnarowska
Keyword(s):  
Surface Roughness ◽  
Environmental Factors ◽  
Climatic Factors ◽  
Incidence Angle ◽  
Surface Layers ◽  
Coating Structure ◽  
Epoxy Coatings ◽  
Coating Surface ◽  
Light Incidence Angle ◽  
Structure Destruction

The paper presents investigation results of climatic as well as environmental factors influence on surface state of three-layer epoxy coatings. A three-year investigation documented substantial destruction of coating surface layers. In particular, a significant increase of aged coating surface roughness, evaluated on the basis of Ra and Rz parameters, was observed. Studies made with SEM corroborated a delamination as well as pigment and filler crumbling from surface layers of coatings. In the final period of ageing craters and superficial cracks appeared in the coating structure. Destruction of aged coating surfaces contributed to their gloss loss by over 98% (for light incidence angle α = 60o) decreasing in this way coating decorative properties.

scholarly journals Bit Error Performance of APD and SPAD Receivers in Optical Wireless Communication

Electronics ◽  
2021 ◽  
Vol 10 (22) ◽  
pp. 2731
Author(s):  
Hiwa Mahmoudi ◽  
Horst Zimmermann
Keyword(s):  
Wireless Communication ◽  
Single Photon ◽  
Incidence Angle ◽  
Wave Model ◽  
Oxide Semiconductor ◽  
Optical Wireless Communication ◽  
Optical Wireless ◽  
Error Performance ◽  
Fully Integrated ◽  
Light Incidence Angle

This review concentrates on the state-of-the-art hardware-oriented receiver aspects for optical wireless communication (OWC), and points to the importance of BER performance analysis and modeling in presence of non-perpendicular light incidence. Receivers in OWC networks for 6G applications have to work for strongly different light incidence angles, to allow the formation of connections to locally separated transceivers without the need for rotation units and accurate adjustment. In turn, and in combination with fully integrated optical receivers, reduction of cost and increased comfort can be achieved. Fully integrated [bipolar] complementary metal-oxide-semiconductor ([Bi]CMOS) receivers with on-chip avalanche photodiodes (APDs) and single-photon avalanche diodes (SPADs) are presented and their performance in optical wireless communication is summarized. Impressive data rates up to 2 Gbit/s and free-space transmission distances up to 27 m at bit error ratios (BER) below 10−9 are reached with linear-mode APD receivers. The importance of optical interference in the isolation and passivation stack on top of the integrated photodiodes is illuminated. To be able to predict the dependence of the BER of single-photon avalanche diode (SPAD) receivers on the light incidence angle, a model, which includes a model for the photon detection probability and a standing-wave model for the isolation and passivation stack, is extended. The dependence of the BER on the light incidence angle onto the photodiodes is investigated by electromagnetic simulation for optical transmission of the layers on top of the photodiode, device simulation for the avalanche triggering probability and BER modeling with MATLAB. It is found that incidence angles up to 30° have moderate influence on the BER and that the BER degrades significantly for incidence angles larger than 50°.

scholarly journals Studying the Effect of Light Incidence Angle on Photoelectric Parameters of Solar Cells by Simulation

2021 ◽  
Vol 10 (4) ◽  
pp. 731-736
Author(s):  
Jasurbek Gulomov ◽  
Rayimjon Aliev ◽  
Avazbek Mirzaalimov ◽  
Navruzbek Mirzaalimov ◽  
Jamshidbek Kakhkhorov ◽  
...  
Keyword(s):  
Solar Cells ◽  
Solar Cell ◽  
Computer Aided Design ◽  
Incidence Angle ◽  
Short Circuit ◽  
Short Circuit Current ◽  
Angular Coefficient ◽  
Light Spectrum ◽  
Frontal Surface ◽  
Light Incidence Angle

It is crucial to examine the dependence of photoelectric parameters of solar cells on the light incidence angle. In the present study, two solar cell models have been developed using the Sentaurus Technology Computer-Aided Design software package. The light spectrum AM1.5 has been directed on the frontal surface of solar cells at different angles. It has been found that the angular coefficient of the photoelectric parameters of a solar cell with nanoparticles included, is two times more than that of a simple solar cell. Besides, it has been found that the efficiency of platinum nanoparticles induced solar cells is 2.15 times greater than simple solar cell efficiency. When the light incidence angle has been varied from 0 to 60 degrees, the short-circuit current has changed by 11% for simple solar cells and by 10% for solar cells with nanoparticles. Further, it has been observed that the variation of power for simple solar cells is 12.5%, while it is 10.5% for solar cells with nanoparticles. In addition, the short-circuit current of solar cells with nanoparticles has been found to be linear within a light incidence angle ranging from 0 to 60 degrees.

scholarly journals SENSITIVITY OF SILICON PHOTOVOLTAIC CONVERTERS TO THE LIGHT INCIDENCE ANGLE ON THEIR RECEIVING SURFACE

2009 ◽  
Vol 6 (3) ◽  
pp. 22-26
Author(s):  
M. V. Kirichenko ◽  
V. R. Kopach ◽  
R. V. Zaitsev ◽  
S. A. Bondarenko
Keyword(s):  
Incidence Angle ◽  
Light Incidence Angle

Sensor of light incidence angle

2018 ◽  
Author(s):  
Jacek Wojtanowski ◽  
Marek Zygmunt ◽  
Andrzej Młodzianko ◽  
Marcin Jakubaszek
Keyword(s):  
Incidence Angle ◽  
Light Incidence Angle

External Reflection Infrared Spectroscopy of Anisotropic Adsorbate Layers on Dielectric Substrates

1997 ◽  
Vol 51 (2) ◽  
pp. 209-217 ◽  
Author(s):  
Helmut Brunner ◽  
Ulrich Mayer ◽  
Helmuth Hoffmann
Keyword(s):  
Infrared Spectroscopy ◽  
Incidence Angle ◽  
Reflection Spectra ◽  
Monolayer Films ◽  
Dielectric Substrates ◽  
Dielectric Surfaces ◽  
Structural Identity ◽  
Light Incidence Angle ◽  
Theory Yield ◽  
Glass Surfaces

Monolayers of octadecylsiloxane were formed on native silicon (Si/SiO2) and glass surfaces by adsorption from dilute solutions of octadecyltrichlor osilane and were investigated by polarization- and angle-dependent external reflection infrared spectroscopy. In contrast to metal substrates, both the parallel and perpendicular vibrational components of the adsorbate can be detected on these dielectric surfaces. The monolayer reflection spectra show significant changes as a function of the light incidence angle and the polarization of the infrared radiation, which contain detailed information on the surface orientation of the film molecules. Spectral simulations based on classical electromagnetic theory yield an average 10° tilt angle of the hydrocarbon chains with respect to the surface normal on both silicon and glass surfaces. Despite this apparent structural identity of the monolayer films on silicon and glass, significant differences are observed in the monolayer reflection spectra resulting from purely optical effects of the substrate.

scholarly journals Prediction of Soc in Calcic Chernozem in the Steppe Zone of Ukraine Using Brightness and Colour Indicators

2021 ◽  
Vol 40 (4) ◽  
pp. 325-336
Author(s):  
Vadym Gorban ◽  
Artem Huslystyi ◽  
José Manuel Recio Espejo ◽  
Natalia Bilova
Keyword(s):  
Image Processing ◽  
Incidence Angle ◽  
Steppe Zone ◽  
Soil Samples ◽  
K Index ◽  
Colour Image ◽  
Light Incidence Angle ◽  
Subsequent Calculation ◽  
Colour Image Processing ◽  
Rgb System

Abstract Soil organic carbon (SOC) is an important component of any soil which determines many of its properties. Nowadays, more and more attention is being paid to the SOC content determination in soils by not using the conventional, time-consuming and expensive technique, but by using colour image processing of soil samples. In this case, even the camera of modern smartphones can be used as an image source, making this technique very convenient and practical. However, it is important to maintain certain standardised conditions (light intensity, light incidence angle, etc.) when capturing the images of soil samples. In our opinion, it is best to use a regular scanner for this purpose, with subsequent image processing by graphic programs (e.g., Adobe Photoshop). To increase the reliability of the colour information obtained in this way, it is desired (if possible) to use a spectrograph or a monochromator in the subsequent calculation of reflection or brightness ratios. It is these two approaches that we have implemented in our work. As a result of the experiment, the values of brightness ratios (at 480, 650 and 750 nm wavelengths and integral brightness ratio), colour indicators (the hue, saturation and value [HSV], red, green and blue [RGB], CIE L*a*b* and cyan, magenta, yellow and key [CMYK] systems) and SOC content in Calcic Chernozem samples of the steppe zone of Ukraine were obtained. Using correlation analysis of the dataset, the existence of direct (r = 0.88–0.90) and inverse close relationships (r = −0.75–0.90) between SOC, values of brightness ratios and colour indicators of the soil samples were established. This allows us to develop predictive models. Statistical analysis showed that the models were significant when they were based on the values of brightness ratios at 650 nm wavelength, integral brightness ratio, V indicator in HSV system, R, G and B indicators in RGB system, C, M and K indicators in CMYK system and L* and b* indicators in L*a*b* system. The subsequent calculation of variation coefficients showed that the largest variability was observed in SOC indicators (CV = 0.72) and slightly less variability in the K index of CMYK system and brightness ratio values at 650 nm wavelength (CV = 0.67 and 0.53, respectively). Based on this, we believe that the models y = 0.0188 + 0.0535*x (x is the value of the K index in CMYK system) and y = 5.0716 – 3.2255*log10(x) (x is the value of brightness ratio at 650 nm wavelength) were the most statistically significant and promising parameters for determining SOC content (y in these equations) in Calcic Chernozem samples of the steppe zone of Ukraine.

Electron Channeling Patterns

1977 ◽  
Vol 35 ◽  
pp. 12-13
Author(s):  
David C. Joy
Keyword(s):  
Electron Diffraction ◽  
Incidence Angle ◽  
Photographic Plate ◽  
Diffraction Effect ◽  
Angle Of Incidence ◽  
Bulk Single Crystal ◽  
Time Resolved ◽  
Electron Channeling ◽  
Spatially Resolved ◽  
Large Bulk

Electron channeling patterns (ECP) were first found by Coates (1967) while observing a large bulk, single crystal of silicon in a scanning electron microscope. The geometric pattern visible was shown to be produced as a result of the changes in the angle of incidence, between the beam and the specimen surface normal, which occur when the sample is examined at low magnification (Booker, Shaw, Whelan and Hirsch 1967).A conventional electron diffraction pattern consists of an angularly resolved intensity distribution in space which may be directly viewed on a fluorescent screen or recorded on a photographic plate. An ECP, on the other hand, is produced as the result of changes in the signal collected by a suitable electron detector as the incidence angle is varied. If an integrating detector is used, or if the beam traverses the surface at a fixed angle, then no channeling contrast will be observed. The ECP is thus a time resolved electron diffraction effect. It can therefore be related to spatially resolved diffraction phenomena by an application of the concepts of reciprocity (Cowley 1969).

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