Оптические свойства кремниевых нанопилларов со встроенным вертикальным p-n-переходом

Resonance reflection of light from the ordered arrays of silicon nanopillars (Si NP) was investigated. The height of Si NP was 450 nm. The effect of Si NP oxidation in concentrated nitric acid on the position of resonances in reflection spectra was studied. A weak influence of the additional polymeric coating on the characteristics of reflection from the structures was proven. It is established on the basis of the results of experimental investigation and direct numerical modeling by means of three-dimensional finite difference time domain algorithm (3D FDTD) that the dependence of the resonant wavelength for Si NP on the diameter of Si NP is a linear function with nonzero displacement depending on the pitch.

Emission, propagation, and reflection of light as mechanical phenomena in inertial frames

The kinematics of balls with mass in the inertial frames is like that in the frame at absolute rest. Practical examples of balls with mass studied at the limit when their mass is zero indicate that the kinematics of massless balls is like that of balls with mass. Light as a wave or particle is a massless entity. Therefore, it is natural to apply the kinematics behavior of the massless balls to light in its interactions with matter during the phenomena of emission and reflection. Thus, the kinematics of light depends on its kinetics of electromagnetic nature and by its mechanical interactions of emission and reflection with the matter. Light behaves in the inertial frames like in the frame at absolute rest, and the speed of light is the constant <mml:math display="inline"> <mml:mi>c</mml:mi> </mml:math> in the inertial frames in which the source and mirror are at rest. The terrestrial experiments with light cannot prove the motion of Earth. This study explains the result of the experiment performed at CERN, Geneva, in 1964. Including the massless balls within Newtonian mechanics, the emission, propagation, and reflection of light can be considered mechanical phenomena.

Opposing hypotheses of the reflection of light applied to the Michelson interferometer with a particular geometry

The derivation of light paths in the Michelson interferometer is based on the hypothesis that the incident speed and reflected speed of the wavefront of a ray of light are equal in the frame at absolute rest. In this case, the Michelson‐Morley experiment predicts a fringe shift of <mml:math display="inline"> <mml:mrow> <mml:mo> </mml:mo> <mml:mn>0.40</mml:mn> </mml:mrow> </mml:math> . With the hypothesis that the incident speed and reflected speed of the wavefront of a ray of light are equal in the inertial frame of a mirror at the instance of collision, the Michelson interferometer with a particular geometry predicts zero fringe shift, which is in agreement with the result of the Michelson‐Morley experiment.

Analysis of the optical properties of the silvery spots on the wings of the Gulf Fritillary, Dione vanillae

The ventral face of the wings of the butterfly Dione vanillae is covered with bright and shiny silvery spots. These areas contain densely packed ground- and coverscales with a bright metallic appearance reflecting more than 50% of light uniformly over the visible range. Our analysis shows that this optically attractive feature is caused by the inner microstructure of the scales located in these areas. Electron microscopy of cross sections through the scales shows that upper and lower lamina, supporting trabeculae, and topping ridges can be approximated by a ‘circus tent’-like geometry. By simulating its optical properties, we show that a moderate disorder of this geometry is important for the uniform reflection of light resulting in the silvery appearance.

Opposing hypotheses of the reflection of light applied to the Michelson interferometer

The derivation of light paths in the Michelson interferometer is based on the hypothesis that the incident speed and reflected speed of the wavefront of a ray of light are equal in the frame at absolute rest. In this case, the Michelson‐Morley experiment predicts a fringe shift of 0.40. With the hypothesis that the incident speed and reflected speed of the wavefront of a ray of light are equal in the inertial frame of a mirror at the instance of collision, the Michelson‐Morley experiment predicts a fringe shift of 0.40 × 10−4, which is in agreement with the experimental result.

Effects of Scattering of Luminescent Down-Shifting Particles Inside Ethylene-Vinyl Acetate Films on Reflection of Light

Silicon solar cells are suffering from a poor spectral response in short wavelength ranges due to the loss of higher energy photons. The luminescent down-shifting (LDS) materials have the ability to convert shorter wavelength photons into longer wavelength photons and improve the performance of the solar cells. However, besides the down-shifting effects, the introduction of LDS particles into ethylene-vinyl acetate (EVA) films on the solar cells also increases surface reflection, which will negatively influence the performance of the solar cells. In this study, the influence of the size of LDS particles inside EVA films on reflection is investigated theoretically. The results showed that the reflection results from the scattering by LDS particles, which depends on the particle’s size. The total reflection caused by LDS particles can be calculated according to the size distribution of LDS particles. This study is helpful in selecting LDS particles that can be applied to solar cells.

Diagnostic Accuracy of Red Reflex Test (RRT) for Early Detection of Ocular Abnormalities in Newborn

Background: The Red Reflex is described as the red to orange reflection of light from the fundus of the eye, observed while using a retinoscope or an ophthalmoscope. Red Eye Reflex Test is determined by the optical media transparency which includes vitreous humor, aqueous humor, cornea and tear film and reflection of light from the back of the eye (fundus) through optical media and into the aperture of the ophthalmoscope. Factors that will block or impede the passage of light through this transparent media or affects its reflection back from fundus will produce an abnormal Red Eye Reflex. Red Eye Reflex (RER) testing is important & effective tool for early detection of ocular abnormalities such as retinal abnormalities, cataract, retinoblastoma and glaucoma. Red reflex is cost effective, can be performed very easily, requires minimal setting, can screen important ocular abnormalities and facilitate their early detection with prompt intervention to prevent long term sequelae associated with the disease. Aim: To find out the diagnostic accuracy of Red Reflex test for diagnosing ocular abnormalities in newborns. Methodology: Ours will be a prospective cross-sectional study where RER examination will be performed within one week of birth of a newborn in a darkened and will correlate the examination findings with respect to ocular findings determined by ophthalmologist to determine its efficacy, sensitivity and specificity in detecting neonatal ocular abnormalities. Expected results: After completion of the study we will be able to determine the accuracy of RRT for ocular abnormality detection in the neonates. We will be able to determine the sensitivity, specificity, PPV & NPV of the red reflex test. If the specificity and the sensitivity is good then we can use RRT as a routine screening method for detection of intraocular abnormalities. Conclusion: To find the Red reflex Test efficacy in screening of the ocular abnormalities in the new born.