Results 31 to 40 of about 342,349 (349)

Super-Dispersive Demultiplexer Design Using Positive-Negative Refraction Boundary and Hetero-Photonic Crystals [PDF]

, 2022
In this paper, a systematic approach is employed to design a photonic crystal with a boundary between positive and negative refraction to boost the refractive properties of the crystal. Mathematical techniques are employed to turn the process of EFC engineering into a nearly mechanical process free of trial-and-error steps.
arxiv   +1 more source

Associations with photoreceptor thickness measures in the UK Biobank. [PDF]

, 2019
Spectral-domain OCT (SD-OCT) provides high resolution images enabling identification of individual retinal layers. We included 32,923 participants aged 40-69 years old from UK Biobank.
Aslam, Tariq, Balaskas, Konstantinos, Barman, Sarah A, Barrett, Jenny H, Bishop, Paul, Blows, Peter, Bunce, Catey, Carare, Roxana O, Chakravarthy, Usha, Chan, Michelle, Chua, Sharon YL, Consortium, UK Biobank Eye Vision, Crabb, David P, Cumberland, Philippa M, Day, Alexander, Desai, Parul, Dhillon, Baljean, Dick, Andrew D, Egan, Cathy, Ennis, Sarah, Foster, Paul J, Fruttiger, Marcus, Gallacher, John EJ, Garway-Heath, David F, Gibson, Jane, Gore, Dan, Guggenheim, Jeremy A, Hammond, Chris J, Hardcastle, Alison, Harding, Simon P, Hogg, Ruth E, Hysi, Pirro, Keane, Pearse A, Khaw, Sir Peng T, Khawaja, Anthony P, Lascaratos, Gerassimos, Lotery, Andrew J, Macgillivray, Tom, Mackie, Sarah, Martin, Keith, Mcgaughey, Michelle, Mcguinness, Bernadette, Mckay, Gareth J, Mckibbin, Martin, Mitry, Danny, Moore, Tony, Morgan, James E, Muthy, Zaynah A, O'Sullivan, Eoin, Owen, Chris G, Patel, Praveen J, Paterson, Euan, Peto, Tunde, Petzold, Axel, Rahi, Jugnoo S, Reisman, Charles, Rudnicka, Alicja R, Self, Jay, Sivaprasad, Sobha, Steel, David, Stratton, Irene, Strouthidis, Nicholas, Sudlow, Cathie, Tapp, Robyn, Thaung, Caroline, Thomas, Dhanes, Trucco, Emanuele, Tufail, Adnan, Vernon, Stephen A, Viswanathan, Ananth C, Vitart, Veronique, Williams, Cathy, Williams, Katie, Woodside, Jayne V, Yang, Qi, Yates, Max M, Yip, Jennifer, Zheng, Yalin   +77 more
core   +10 more sources

Refractive error among school children in Jhapa, Nepal

Journal of Optometry, 2011
Purpose: To evaluate the pattern of refractive errors among school children in Jhapa, Nepal. Methods: A cross-sectional study was designed to evaluate refractive status of 2236 school children in three government schools and a private school.
Gauri Shankar Shrestha, Digen Sujakhu, Purushottam Joshi   +2 more
doaj   +1 more source

Towards Automating Retinoscopy for Refractive Error Diagnosis [PDF]

arXiv, 2022
Refractive error is the most common eye disorder and is the key cause behind correctable visual impairment, responsible for nearly 80% of the visual impairment in the US. Refractive error can be diagnosed using multiple methods, including subjective refraction, retinoscopy, and autorefractors.
arxiv  

Atmospheric Refractive Electromagnetic Wave Bending and Propagation Delay [PDF]

PASP 127, 947, p. 74-91, 2015, 2014
In this tutorial we summarize the physics and mathematics behind refractive electromagnetic wave bending and delay. Refractive bending and delay through the Earth's atmosphere at both radio/millimetric and optical/IR wavelengths are discussed, but with most emphasis on the former, and with Atacama Large Millimeter Array (ALMA) applications in mind.
arxiv   +1 more source

Refractive error is associated with intracranial volume [PDF]

, 2018
Myopia is part of the spectrum of refractive error. Myopia is associated with psychometric intelligence and, the link between brain anatomy and myopia has been hypothesized.
Araki, T, Hanawa, S, Iizuka, K, Ikeda, S, Kawashima, R, Kotozaki, Y, Magistro, D, Miyauchi, CM, Nakagawa, S, Nouchi, R, Nozawa, T, Sakaki, K, Sassa, Y, Sekiguchi, A, Shinada, T, Takeuchi, H, Taki, Y, Yamamoto, Y, Yokota, S, Yokoyama, R   +19 more
core   +3 more sources

Changes in forward light scatter parameters as a function of refractive error in young adults [PDF]

, 2020
Background/aims Some aspects of visual performance worsen with increasing myopia. Whilst the underlying causes are not always clear, reduction in retinal image quality is often attributed to structural changes in the posterior myopic eye.
Barbur, J., Nagra, M., Patel, M.
core   +2 more sources

Prevalence of Refractive Error and Strabismus in Primary School Children of Tehsil Lakki Marwat, Khyber Pakhtunkhwa Pakistan

Journal of Gandhara Medical and Dental Sciences, 2020
OBJECTIVES: Refractive errors and strabismus continue to remain a significant public health problem. Among school children it has an impact on child development.
Faheem Ullah, Naheed Mahsood, Waqas Mohyuddin, Saadullah Afridi, Zia ur Rehman   +4 more
doaj   +1 more source

Refractive error and its associated factors among pregnant women attending antenatal care unit at the University of Gondar Comprehensive Specialized Hospital, Northwest Ethiopia.

PLoS ONE, 2021
BackgroundRefractive error is one of the commonly encountered problems during pregnancy and being the cause of deleterious effects on health. Despite its impacts, there is no evidence on the magnitude and associated factors of refractive error among ...
Mengistie Diress, Yigizie Yeshaw, Minychil Bantihun, Baye Dagnew, Adugnaw Ambelu, Mohammed Abdu Seid, Yonas Akalu   +6 more
doaj   +1 more source

The Cryogenic Refractive Indices of S-FTM16, a Unique Optical Glass for Near-Infrared Instruments [PDF]

Publ.Astron.Soc.Pac. 116 (2004) 833, 2004
The Ohara glass S-FTM16 is of considerable interest for near-infrared optical designs because it transmits well through the K band and because negative S-FTM16 elements can be used to accurately achromatize positive calcium fluoride elements in refractive collimators and cameras.
arxiv   +1 more source