Glossary
Searchable terminology from accessibility, web standards, and related fields.
74 results found in Visual Impairment.
- Adventitious blindness (Acquired blindness, Late blindness, Acquired visual impairment)
- Vision loss that occurs after a period of sighted experience, as opposed to congenital blindness (present from birth). People with adventitious blindness retain visual memories, mental imagery, and fa…
- Age-Related Vision Loss (Age-Related Visual Impairment)
- Vision impairment that occurs as a consequence of aging, representing the most common cause of blindness and low vision worldwide. Conditions include age-related macular degeneration, glaucoma, diabet…
- Albinism (Oculocutaneous Albinism, Ocular Albinism)
- A group of inherited conditions characterized by reduced or absent melanin pigment production, affecting the skin, hair, and eyes. Ocular effects commonly include reduced visual acuity, nystagmus (inv…
- Amblyopia (Lazy eye)
- A neurodevelopmental vision disorder in which one eye has reduced visual acuity that cannot be fully corrected with glasses or contact lenses, caused by abnormal visual development in early childhood.…
- Assisted Photography (Accessible Photography, Camera Aiming Assistance)
- Assisted photography refers to technologies and techniques that help people with visual impairments take photographs by providing non-visual feedback about camera aiming, composition, and image qualit…
- Astigmatism
- A common refractive error caused by an irregularly shaped cornea or lens, resulting in blurred or distorted vision at all distances. The cornea is shaped more like a rugby ball than a sphere, causing …
- Audio Enriched Links (AEL, Audio Link Preview)
- A JAWS screen reader extension that provides spoken previews of linked web pages before a blind user follows a hyperlink. When activated on a focused link, the system fetches the destination page in t…
- Blind (Blindness)
- A visual impairment severe enough that a person cannot use vision as their primary means of perceiving information, typically defined legally in the United States as best-corrected visual acuity of 20…
- Blindness (Blind, Total Blindness, Complete Vision Loss)
- A condition characterised by the complete or near-complete absence of functional vision, ranging from no light perception to minimal light awareness that cannot be used for practical tasks. Blind indi…
- Braille Mathematics (Math Braille, Braille Math Notation)
- The various systems of Braille codes designed specifically to represent mathematical expressions, formulas, and notation in a tactile format readable by blind individuals. Because standard literary Br…
- Bus stop accessibility (Accessible bus stops, Bus stop landmarks)
- The design, infrastructure, and information features that make bus stops findable, identifiable, and usable by people with disabilities. For blind and low-vision riders, bus stop accessibility depends…
- Central Vision Loss (Central Field Loss, Central Scotoma)
- Loss of vision in the central part of the visual field, typically caused by damage to the macula — the area of the retina responsible for sharp, detailed vision. People with central vision loss experi…
- Color Identifier (Color Detector, Color Recognition Device)
- A color identifier is an assistive technology device or application that detects and announces the color of objects for people with vision impairments. Standalone hardware devices use a light sensor p…
- Color Perception (Color Vision, Chromatic Vision)
- Color perception is the ability to detect, distinguish, and identify colors. Impairments in color perception range from complete color blindness (achromatopsia) to partial deficiencies in distinguishi…
- Cone Dystrophy (Cone-Rod Dystrophy)
- A group of inherited eye disorders that affect the cone cells in the retina, which are responsible for color vision, central vision, and visual acuity in well-lit conditions. People with cone dystroph…
- Currency Accessibility (Accessible Currency, Banknote Accessibility)
- The design of physical money — coins and banknotes — so that people with visual impairments or other disabilities can independently identify and use different denominations. Many countries produce ban…
- Dichoptic presentation (Dichoptic display, Dichoptic filtering, Dichoptic stimulation)
- A technique in which different visual information is presented separately to each eye, typically using color-filtered glasses (red-cyan or red-green anaglyph), polarized lenses, or head-mounted displa…
- EVITA (Enabling Visually Impaired Table Access)
- A specialized table browser developed at the University of Manchester designed to enable visually impaired users to navigate, browse, and read HTML data tables non-visually in a manner analogous to ho…
- Eccentric viewing (Preferred retinal locus, PRL)
- A viewing strategy used by people with central vision loss (such as from macular degeneration) in which they learn to look slightly off-center to use a healthier area of the retina instead of the dama…
- Eyes-free Interaction (Eyes-free Input, Nonvisual Interaction, Eyes-free Interface)
- Interaction techniques that allow users to operate devices without looking at the screen or interface. Eyes-free interaction is essential for people who are blind, but also benefits sighted users in c…