Glasses, also known as eyeglasses or spectacles, are vision eyewear, with lenses mounted in a frame that holds them in front of a person's eyes, typically utilizing a bridge over the nose and hinged arms that rest over the ears.
Myopia, also known as near-sightedness and short-sightedness, is an eye disorder where light focuses in front of, instead of on, the retina. As a result, distant objects appear blurry while close objects appear normal. Other symptoms may include headaches and eye strain. Severe near-sightedness is associated with an increased risk of retinal detachment, cataracts, and glaucoma.
A dioptre or diopter is a unit of measurement with dimension of reciprocal length, equivalent to one reciprocal metre, 1 dioptre = 1 m−1. It is normally used to express the optical power of a lens or curved mirror, which is a physical quantity equal to the reciprocal of the focal length, expressed in metres. For example, a 3-dioptre lens brings parallel rays of light to focus at 1⁄3 metre. A flat window has an optical power of zero dioptres, as it does not cause light to converge or diverge. Dioptres are also sometimes used for other reciprocals of distance, particularly radii of curvature and the vergence of optical beams.
Optometry is a specialized health care profession that involves examining the eyes and related structures for defects or abnormalities. Optometrists are health care professionals who typically provide comprehensive primary eye care.
The Bates method is an ineffective and potentially dangerous alternative therapy aimed at improving eyesight. Eye-care physician William Horatio Bates (1860–1931) held the erroneous belief that the extraocular muscles effected changes in focus and that "mental strain" caused abnormal action of these muscles; hence he believed that relieving such "strain" would cure defective vision. In 1952, optometry professor Elwin Marg wrote of Bates, "Most of his claims and almost all of his theories have been considered false by practically all visual scientists."
Refractive error, also known as refraction error, is a problem with focusing light accurately on the retina due to the shape of the eye and or cornea. The most common types of refractive error are near-sightedness, far-sightedness, astigmatism, and presbyopia. Near-sightedness results in far away objects being blurry, far-sightedness and presbyopia result in close objects being blurry, and astigmatism causes objects to appear stretched out or blurry. Other symptoms may include double vision, headaches, and eye strain.
The Lions Eye Institute (LEI) is an Australian medical research institute affiliated with the University of Western Australia. It was established in 1983 with support of the Lions Clubs of Western Australia and headquartered in the Perth suburb of Nedlands, Western Australia. The LEI is a not-for-profit centre of excellence that combines an ophthalmic clinic with scientific discovery developing techniques for the prevention of blindness and the reduction of pain from blinding eye conditions.
Joshua D. Silver is a British physicist whose discoveries have included a new way to change the curvature of lenses, with a significant application for the low-cost manufacture of corrective lenses and adjustable spectacles, especially in low-income countries.
Astigmatism is a type of refractive error due to rotational asymmetry in the eye's refractive power. This results in distorted or blurred vision at any distance. Other symptoms can include eyestrain, headaches, and trouble driving at night. Astigmatism often occurs at birth and can change or develop later in life. If it occurs in early life and is left untreated, it may result in amblyopia.
Emmetropia is the state of vision in which a faraway object at infinity is in sharp focus with the ciliary muscle in a relaxed state. That condition of the normal eye is achieved when the refractive power of the cornea and eye lens and the axial length of the eye balance out, which focuses rays exactly on the retina, resulting in perfectly sharp distance vision. A human eye in a state of emmetropia requires no corrective lenses for distance; the vision scores well on a visual acuity test.
Vision Aid Overseas (VAO) is a registered charity in the United Kingdom, which provides optical aid and services to developing countries in Africa.
Jennifer Semakula Musisi is a Ugandan lawyer and public administrator. She is the first City Leader in Residence at Bloomberg Harvard City Leadership Initiative at the Ash Center of the Harvard Kennedy School, in Cambridge, Massachusetts, United States. She was appointed to this position in January 2019.
Professor Charles Mark Lwanga Olweny, MBChB, MMed, MD, FRACP, is a Ugandan physician, oncologist, academic and medical researcher. Currently he is a professor of medicine and Immediate past vice-chancellor at Uganda Martyrs University, based at Nkozi, Mpigi District, in Central Uganda.
The Australian College of Optometry (ACO) is a not-for-profit organisation in Australia committed to improving the eye health and well-being of Australian communities. Established in 1940, the ACO delivers public health optometry, vision research and professional education.
Some animals suffer from shortsightedness and have poor eyesight. In domestic animals, myopia, with or without astigmatism, occurs frequently.
Gerard Sutton is an Australian ophthalmic surgeon and ophthalmologist in Australia and New Zealand. His specialty is laser vision correction, cataract and lens surgery, and corneal transplantation.
Uganda Heart Institute (UHI), is a specialized, public, tertiary care medical facility owned by the Uganda Ministry of Health. It is a component of Mulago National Referral Hospital, the largest hospital in Uganda, which serves as the teaching hospital of Makerere University College of Health Sciences.
Science and technology in Uganda examines government efforts to develop a national innovation system and the impact of these policies.
Clare Gilbert is a professor and a researcher who focuses on blindness in children based at the London School of Hygiene and Tropical Medicine (LSHTM).
The Singapore National Eye Centre (SNEC) is a national eye specialty centre in Singapore.
