Results 51 to 60 of about 771,659 (382)

Design of Binary-Sequence Zone Plates in High Wavelength Domains

Sensors, 2018
The design of zone plates is an important topic in many areas of physics, such as optics, X-rays, microwaves or ultrasonics. In this paper, a zone plate design method, which provides high flexibility in the shaping of the focusing profile, is analyzed ...
José Miguel Fuster, Sergio Pérez-López, Pilar Candelas, Constanza Rubio   +3 more
doaj   +1 more source

Photoaligned Liquid Crystalline Structures for Photonic Applications

Crystals, 2023
With the advancement of information display technologies, research on liquid crystals is undergoing a tremendous shift to photonic devices. For example, devices and configurations based on liquid crystal materials are being developed for various ...
Aleksey Kudreyko, Vladimir Chigrinov, Gurumurthy Hegde, Denis Chausov   +3 more
doaj   +1 more source

Gravitational Lenses

, 1999
The purpose of these lecture notes is to describe the gravitational lens effects in different astrophysical contexts. These notes are voluntarily focused on the fundamental mechanisms and the basic concepts that are useful to describe these effects.
Bernardeau, F.
core   +2 more sources

Randomized controlled trial of anterior-chamber intraocular lenses in Nepal: long-term follow-up

Bulletin of the World Health Organization
Most of the estimated 20 million people who are blind with cataracts live in rural areas of developing countries, where expert surgical resources are scarce.
J.R. Evans, A. Hennig, D. Pradhan, A. Foster, R. Lagnado, A. Poulson, G.J. Johnson, R.P.L. Wormald   +7 more
doaj   +1 more source

3D Printed Radar Lenses with Anti-Reflective Structures

Designs, 2019
Background: The purpose of this study was to determine if 3D printed lenses with wavelength specific anti-reflective (AR) surface structures would improve beam intensity and thus radar efficiency for a Printed Circuit Board (PCB)-based 60 GHz radar. This
Ross J. Friel, Maria Gerling-Gerdin, Emil Nilsson, Björn P. Andreasson   +3 more
doaj   +1 more source

Using two-dimensional graphene lenses to increase the effectiveness of solar panels

Revue des Énergies Renouvelables, 2023
We aim to enhance the efficiency of solar panels by covering them with graphene lenses that collect and concentrate light rays onto the panels. The simulation was performed using the Monte Carlo method and provided precise results regarding the ...
Abid Boudiar, Habala Bendifallah, Faten Ziani   +2 more
doaj   +1 more source

Double-impulse magnetic focusing of launched cold atoms. [PDF]

, 2005
We have theoretically investigated three-dimensional focusing of a launched cloud of cold atoms using a pair of magnetic lens pulses (the alternate-gradient method). Individual lenses focus radially and defocus axially or vice versa.
Aidan S Arnold, Arnold A S, David A Smith, Earnshaw S, Folman R, Grimm R, Hinds E A, Hughes I G, Hughes I G, Hughes I G, Ifan G Hughes, Lawson J D, Matthew J Pritchard, Meschede D, Murray D R, Pritchard M J, Salomon Ch, Sidorov A I, Smith D A Pritchard M J Arnold A S Hughes I G   +18 more
core   +2 more sources

A comparison of the contrast sensitivity function between age-matched phakic emmetropes and pseudophakic individuals with aspheric intraocular lenses

Taiwan Journal of Ophthalmology, 2019
PURPOSE: The purpose of this study is to compare the contrast sensitivity function (CSF) between eyes of age-matched individuals with aspheric intraocular lens (IOL) and emmetropia.
Undrakonda Vivekanand, Yogish Subraya Kamath   +1 more
doaj   +1 more source

Evolutionary interplay between viruses and R‐loops

FEBS Letters, EarlyView.
Viruses interact with specialized nucleic acid structures called R‐loops to influence host transcription, epigenetic states, latency, and immune evasion. This Perspective examines the roles of R‐loops in viral replication, integration, and silencing, and how viruses co‐opt or avoid these structures.
Zsolt Karányi, Zita Képes, Zoltán Szabó, Eszter Csoma, Lóránt Székvölgyi   +4 more
wiley   +1 more source

On the Nature and Location of the Microlenses [PDF]

, 1999
This paper uses the caustic crossing events in the microlens data sets to explore the nature and location of the lenses. We conclude that the large majority of lenses, whether they are luminous or dark, are likely to be binaries.
Afonso C., Alard C., Alard C., Bissantz N., Dominik M., Dominik M., Dominik M., Dominik M., Goldberg D. M., Goldberg D. M., Palanque-Delabrouille N., Renault C., Rosanne Di Stefano, Udalski A., Udalski A., Udalski A., Udalski A., Udalski A.   +17 more
core   +3 more sources