Results 11 to 20 of about 342,349 (349)
Analytic evaluation of diffuse fluence error in multi-layer scattering media with discontinuous refractive index [PDF]
, 2011 A simple analytic method of estimating the error involved in using an approximate boundary condition for diffuse radiation in two adjoining scattering media with differing refractive index is presented. The method is based on asymptotic planar fluences and enables the relative error to be readily evaluated without recourse to Monte Carlo simulation ...
Adrian C. Selden, Liemert
arxiv +3 more sources
Surgical Options for the Refractive Correction of Keratoconus: Myth or Reality [PDF]
Journal of Ophthalmology, 2017 Keratoconus provides a decrease of quality of life to the patients who suffer from it. The treatment used as well as the method to correct the refractive error of these patients may influence on the impact of the disease on their quality of life.
L. Fernández-Vega-Cueto +6 more
doaj +6 more sources
Journal of Ophthalmic & Vision Research, 2023 Purpose: This study aimed to assess the agreement between topographic indices of healthy subjects and keratoconus (KCN) patients using a swept-source optical coherence tomography (SS-OCT CASIA2) versus a Scheimpflug camera (Pentacam). Methods: 40 eyes of
Hamed Ghassemi +5 more
doaj +1 more source
Journal of Nepal Medical Association, 2023 Introduction: Refractive error is the inability of eyes to focus clearly on images. Visual impairment due to refractive error has a major impact on children's education and daily activities.
Govind Gurung, Krishna Kant Gupta
doaj +1 more source
Distribution of refractive error among chinese primary school children in a rural area in Pahang, Malaysia [PDF]
Malaysian Family Physician, 2022 Purpose: This study aimed to determine the prevalence and status of refractive error among Chinese primary school children in a rural area in Pahang. Methods: This investigation entailed a cross-sectional retrospective study design involving case file ...
Rokiah Omar +3 more
doaj +1 more source
Measurement error of tracer-based velocimetry in single-phase turbulent flows with inhomogeneous refractive indices [PDF]
Exp. Therm. Fluid Sci., 136:110681 (2022), 2022 Inhomogeneous refractive index fields lead to errors in optical flow velocity measurements. Former respective studies are mostly in quasi two-dimensional flows, and attribute the measurement errors to spatial gradients in the refractive index field, while less attention has been paid to flows with three-dimensional refractive index fields which usually
arxiv +1 more source
Deutsches Ärzteblatt international, 2016 All over the world, refractive errors are among the most frequently occuring treatable distur - bances of visual function. Ametropias have a prevalence of nearly 70% among adults in Germany and are thus of great epidemiologic and socio-economic relevance.In the light of their own clinical experience, the authors review pertinent articles retrieved by a
Peter Baumbach +4 more
openaire +3 more sources
Calculating the error in refractive error [PDF]
Eye, 2011 To demonstrate a quick way of calculating the optical difference between two refractions using vector analysis, and to express this as a score for examination purposes.An existing formula is applied, converted to a defocus equivalent, and then converted to a score.
R B Ellingham +3 more
openaire +3 more sources
PLoS ONE, 2022 IntroductionGlobally, the prevalence of refractive error was 12%, and visual impairment due to refractive error was 2.1%. In sub-Saharan Africa, the prevalence of refractive error and visual impairment due to refractive error was 12.6% and 3.4 ...
Daniel Atlaw +15 more
doaj +1 more source
Prevalence of refractive errors among the school-going children in East Sikkim
Indian Journal of Ophthalmology, 2021 Purpose: Vision plays an important role in child's development for learning and communication. Uncorrected refractive error (URE) has become a major challenge to health care policy makers especially in school going children.
Karma Loday Bhutia +3 more
doaj +1 more source