Blindness is the condition of lacking visual perception due to physiological or neurological factors. Look up blindness in Wiktionary, the free dictionary. ... In psychology, visual perception is the ability to interpret visible light information reaching the eyes which is then made available for planning and action. ... Physiology (in Greek physis = nature and logos = word) is the study of the mechanical, physical, and biochemical functions of living organisms. ... Neurology is a branch of medicine dealing with disorders of the central and peripheral nervous systems. ...

Various scales have been developed to describe the extent of vision loss and define "blindness."^[1] Total blindness is the complete lack of form and light perception and is clinically recorded as "NLP," an abbreviation for "no light perception."^[1] Blindness is frequently used to describe severe visual impairment with residual vision. Those described as having only "light perception" can see no more than the ability to tell light from dark. A person with only "light projection" can tell the general direction of a light source. Visual loss results in the absence of vision where it existed before, which can happen either acutely (i. ... Visual impairment is the functional loss of vision. ...

In order to determine which people may need special assistance because of their visual disabilities, various governmental jurisdictions have formulated more complex definitions referred to as legal blindness.^[2] In North America and most of Europe, legal blindness is defined as visual acuity (vision) of 20/200 (6/60) or less in the better eye with best correction possible. This means that a legally blind individual would have to stand 20 feet (6 m) from an object to see it with the same degree of clarity as a normally sighted person could from 200 feet (60 m). In many areas, people with average acuity who nonetheless have a visual field of less than 20 degrees (the norm being 180 degrees) are also classified as being legally blind. Approximately ten percent of those deemed legally blind, by any measure, have no vision. The rest have some vision, from light perception alone to relatively good acuity. Low vision is sometimes used to describe visual acuities from 20/70 to 20/200. [1] North America North America is a continent [1] in the Earths northern hemisphere and (chiefly) western hemisphere. ... For other uses, see Europe (disambiguation). ... Traditional Snellen chart used for visual acuity testing. ... The term visual field is sometimes used as a synonym to field of view, though they do not designate the same thing. ... This article describes the unit of angle. ... Low vision is alternatively a general term used to describe lowered visual acuity, and a specific legal term in Canada and the United States used to designate someone with vision of 20/70 or less in the better eye with correction. ...

By the 10th Revision of the WHO International Statistical Classification of Diseases, Injuries and Causes of Death, low vision is defined as visual acuity of less than 6/18, but equal to or better than 3/60, or corresponding visual field loss to less than 20 degrees, in the better eye with best possible correction. Blindness is defined as visual acuity of less than 3/60, or corresponding visual field loss to less than 10 degrees, in the better eye with best possible correction.[2][3] WHO redirects here. ...

Blindness
Classification & external resources

The Blind Girl (1856), a painting by John Everett Millais
ICD-10	H54.0, H54.1, H54.4
ICD-9	369

Image File history File linksMetadata Download high resolution version (1067x1600, 360 KB) Summary John Everett Millais: The Blind Girl / Die junge Blinde / La fille aveugle 1856 City Museum and Art Gallery, Birmingham Licensing File links The following pages link to this file: Blindness Metadata This file contains additional information, probably... Sir John Everett Millais Sir John Everett Millais, 1st Baronet, PRA (June 8, 1829 – August 13, 1896) was a British painter and illustrator and one of the founders of the Pre-Raphaelite Brotherhood. ... The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify diseases and a wide variety of signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or disease. ... The International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD-10) is a coding of diseases and signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or diseases, as classified by the World Health Organization (WHO). ... // H00-H59 - Diseases of the eye and adnexa (H00-H06) Disorders of eyelid, lacrimal system and orbit (H00) Hordeolum and chalazion (H000) Hordeolum and other deep inflammation of eyelid (H001) Chalazion (H01) Other inflammation of eyelid (H010) Blepharitis (H011) Noninfectious dermatoses of eyelid (H02) Other disorders of eyelid (H020) Entropion... // H00-H59 - Diseases of the eye and adnexa (H00-H06) Disorders of eyelid, lacrimal system and orbit (H00) Hordeolum and chalazion (H000) Hordeolum and other deep inflammation of eyelid (H001) Chalazion (H01) Other inflammation of eyelid (H010) Blepharitis (H011) Noninfectious dermatoses of eyelid (H02) Other disorders of eyelid (H020) Entropion... // H00-H59 - Diseases of the eye and adnexa (H00-H06) Disorders of eyelid, lacrimal system and orbit (H00) Hordeolum and chalazion (H000) Hordeolum and other deep inflammation of eyelid (H001) Chalazion (H01) Other inflammation of eyelid (H010) Blepharitis (H011) Noninfectious dermatoses of eyelid (H02) Other disorders of eyelid (H020) Entropion... The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify diseases and a wide variety of signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or disease. ... The following is a list of codes for International Statistical Classification of Diseases and Related Health Problems. ...

Legal blindness

In 1934, the American Medical Association adopted the following definition of blindness: The American Medical Association (AMA) is the largest association of medical doctors in the United States. ...

"Central visual acuity of 20/200 or less in the better eye with corrective glasses or central visual acuity of more than 20/200 if there is a visual field defect in which the peripheral field is contracted to such an extent that the widest diameter of the visual field subtends an angular distance no greater than 20 degrees in the better eye."^[3]

The United States Congress included this definition as part of the Aid to the Blind program in the Social Security Act passed in 1935^[3][4]. In 1972, the Aid to the Blind program and two others combined under Title XVI of the Social Security Act to form the Supplemental Security Income program[4] which currently states: Type Bicameral Houses Senate House of Representatives President of the Senate President pro tempore Dick Cheney, (R) since January 20, 2001 Robert C. Byrd, (D) since January 4, 2007 Speaker of the House Nancy Pelosi, (D) since January 4, 2007 Members 535 plus 4 Delegates and 1 Resident Commissioner Political... United States Social Security Card Social Security is a social insurance program administered by the Social Security Administration under the authority of the United States federal government. ... Supplemental Security Income is a monthly stipend provided to some citizens by the United States federal government. ...

"An individual shall be considered to be blind for purposes of this title if he has central visual acuity of 20/200 or less in the better eye with the use of a correcting lens. An eye which is accompanied by a limitation in the fields of vision such that the widest diameter of the visual field subtends an angle no greater than 20 degrees shall be considered for purposes of the first sentence of this subsection as having a central visual acuity of 20/200 or less. An individual shall also be considered to be blind for purposes of this title if he is blind as defined under a State plan approved under title X or XVI as in effect for October 1972 and received aid under such plan (on the basis of blindness) for December 1973, so long as he is continuously blind as so defined." ^[5]

Kuwait is one of many nations that share the same criteria for legal blindness^[6].

Epidemiology

In 1987, it was estimated that 598,000 people in the United States met the legal definition of blindness^[7]. Of this number, 58% were over the age of 65^[7]. In 1994-1995, 1.3 million Americans reported legal blindness^[8].

In November 2004 article Magnitude and causes of visual impairment, the WHO estimated that in 2002 there were 161 million (about 2.6% of the world population) visually impaired people in the world, of whom 124 million (about 2%) had low vision and 37 million (about 0.6%) were blind.^[9] WHO redirects here. ...

Causes of blindness

Serious visual impairment has a variety of causes:

Diseases

Most visual impairment is caused by disease and malnutrition. According to WHO estimates in 2002, the most common causes of blindness around the world are: This article is about the medical term. ... Percentage of population affected by malnutrition by country, according to United Nations statistics. ... WHO redirects here. ...

• cataracts (47.8%),
• glaucoma (12.3%),
• uveitis (10.2%),
• age-related macular degeneration (AMD) (8.7%),
• trachoma (3.6%),
• corneal opacity (5.1%), and
• diabetic retinopathy (4.8%), among other causes.

People in developing countries are significantly more likely to experience visual impairment as a consequence of treatable or preventable conditions than are their counterparts in the developed world. While vision impairment is most common in people over age 60 across all regions, children in poorer communities are more likely to be affected by blinding diseases than are their more affluent peers. Cataract is also used to mean a waterfall or where the flow of a river changes dramatically. ... Uveitis specifically refers to inflammation of the middle layer of the eye, termed the uvea but in common usage may refer to any inflammatory process involving the interior of the eye. ... Listen to this article ( info/dl) This audio file was created from an article revision dated 2005-07-19, and may not reflect subsequent edits to the article. ... The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber, providing most of an eyes optical power [1]. Together with the lens, the cornea refracts light and, as a result, helps the eye to focus. ... Diabetic retinopathy is retinopathy (damage to the retina) caused by complications of diabetes mellitus, which could eventually lead to blindness. ...

The link between poverty and treatable visual impairment is most obvious when conducting regional comparisons of cause. Most adult visual impairment in North America and Western Europe is related to age-related macular degeneration and diabetic retinopathy. While both of these conditions are subject to treatment, neither can be cured. Another common cause is retinopathy of prematurity. A boy from an East Cipinang trash dump slum in Jakarta, Indonesia shows what he found. ... North America North America is a continent [1] in the Earths northern hemisphere and (chiefly) western hemisphere. ... A current understanding of Western Europe. ... Retinopathy of prematurity (ROP), previously known as retrolental fibroplasia (RLF), is a disease of the eye that affects prematurely born babies. ...

In developing countries, wherein people have shorter life expectancies, cataracts and water-borne parasites—both of which can be treated effectively—are most often the culprits (see River blindness, for example). Of the estimated 40 million blind people located around the world, 70–80% can have some or all of their sight restored through treatment. Binomial name Onchocerca volvulus Bickel 1982 Onchocerciasis (pronounced ) or river blindness is the worlds second leading infectious cause of blindness. ...

In developed countries where parasitic diseases are less common and cataract surgery is more available, age-related macular degeneration, glaucoma, and diabetic retinopathy are usually the leading causes of blindness^[10]. Cataract surgery is the removal of the lens of the eye that has developed a cataract. ...

Abnormalities and injuries

Eye injuries, most often occurring in people under 30, are the leading cause of monocular blindness (vision loss in one eye) throughout the United States. Injuries and cataracts affect the eye itself, while abnormalities such as optic nerve hypoplasia affect the nerve bundle that sends signals from the eye to the back of the brain, which can lead to decreased visual acuity. Optic nerve hypoplasia is a medical condition that results in underdevelopment of the optic nerves. ...

People with injuries to the occipital lobe of the brain can, despite having undamaged eyes and optic nerves, still be legally or totally blind. The occipital lobe is the visual processing center of the mammalian brain, containing most of the anatomical region of the visual cortex. ... Human brain In animals, the brain (enkephale) (Greek for in the skull), is the control center of the central nervous system, responsible for behavior. ... This article is about the anatomical structure. ...

Genetic defects

People with albinism often suffer from visual impairment to the extent that many are legally blind, though few of them actually cannot see. Leber's congenital amaurosis can cause total blindness or severe sight loss from birth or early childhood. Albino redirects here. ... Lebers congenital amaurosis is a rare inherited eye disease that appears at birth or in the first few months of life, typically characterized by nystagmus, sluggish or no pupillary responses, and severe vision loss or blindness. ...

Recent advances in mapping the human genome have identified other genetic causes of low vision or blindness. One such example is Bardet-Biedl syndrome. A genetic map is a chromosome map of a species or experimental population that shows the position of its known genes and/or markers relative to each other, rather than as specific physical points on each chromosome. ... A graphical representation of the normal human karyotype. ... Low vision is alternatively a general term used to describe lowered visual acuity, and a specific legal term in Canada and the United States used to designate someone with vision of 20/70 or less in the better eye with correction. ... The Bardet-Biedl syndrome is a a syndrome characterized mainly by obesity, pigmentary retinopathy, polydactyly, mental retardation, hypogonadism, and renal failure in fatal cases. ...

Poisoning

A small portion of all cases of blindness are caused by the intake of certain chemicals. A well-known example is methanol ^[11] , found in methylated spirits, which are sometimes used by alcoholics as a cheap substitute for regular alcoholic beverages. Methanol, also known as methyl alcohol, carbinol, wood alcohol, wood naptha or wood spirits, is a chemical compound with chemical formula CH3OH. It is the simplest alcohol, and is a light, volatile, colourless, flammable, poisonous liquid with a distinctive odor that is somewhat milder and sweeter than ethanol (ethyl alcohol). ... Methylated spirit (or Meths) is ethanol which has been dyed and rendered undrinkable, and is used for purposes such as fuel for spirit burners or as a solvent. ... Alcoholism is the consumption of, or preoccupation with, alcoholic beverages to the extent that this behavior interferes with the drinkers normal personal, family, social, or work life, and may lead to physical or mental harm. ... Alcoholic beverages are drinks containing ethanol, popularly called alcohol. ...

Willful actions

Blinding has been used as an act of vengeance and torture in some instances, to deprive a person of a major sense by which they can navigate or interact within the world, act fully independently, and be aware of events surrounding them. An example from the classical realm is Oedipus, who gouges out his own eyes after realizing that he fulfilled the awful prophecy spoken of him. For other uses, see Torture (disambiguation). ...

Blindness prevention

There exist a number of organizations, such as International Agency for the Prevention of Blindness, ORBIS International, and Seva Foundation, who have developed programs aimed at preventing blindness. The International Agency for the Prevention of Blindness (IAPB) is a coordinating, umbrella organization to lead an international effort in mobilizing resources for blindness prevention activities. ... ORBIS International is an international non-profit non-governmental organization (NGO) focusing on prevention of blindness and the treatment of eye diseases in developing countries. ... The Seva Foundation is a non-profit foundation, founded in December, 1978, and funded by donation, whose goal is to build partnerships to respond to locally defined problems with culturally sustainable solutions throughout the world. ...

On September 10, 2007, in a 6-year study, researchers, led by John Paul SanGiovanni of the National Eye Institute, Maryland found that Lutein and zeaxanthin (nutrients in eggs, spinach and other green vegetables) protect against blindness (macular degeneration), affecting 1.2 million Americans, mostly after age 65. Lutein and zeaxanthin reduce the risk of AMD (journal Archives of Ophthalmology). Foods considered good sources of the nutrients also include kale, turnip greens, collard greens, romaine lettuce, broccoli, zucchini, corn, garden peas and Brussels sprouts.^[12] For the suburb of Melbourne, Australia, see Research, Victoria. ... The National Eye Institute (NEI) is one of the US National Institutes of Health that was established in 1968. ... Official language(s) None (English, de facto) Capital Annapolis Largest city Baltimore Largest metro area Baltimore-Washington Metropolitan Area Area  Ranked 42nd  - Total 12,407 sq mi (32,133 km²)  - Width 101 miles (145 km)  - Length 249 miles (400 km)  - % water 21  - Latitude 37° 53′ N to 39° 43′ N... Lutein (LOO-teen) (from Latin lutea meaning yellow) is one of over 600 known naturally occurring carotenoids. ... Nutrients and the body A nutrient is any element or compound necessary for or contributing to an organisms metabolism, growth, or other functioning. ... Chicken egg (left) and quail eggs (right), the types of egg commonly used as food An egg is a body consisting of an ovum surrounded by layers of membranes and an outer casing of some type, which acts to nourish and protect a developing embryo. ... Binomial name Spinacia oleracea L. Percentages are relative to US recommendations for adults. ... For other uses, see Green (disambiguation). ... Vegetables on a market Vegetable is a nutritional and culinary term denoting any part of a plant that is commonly consumed by humans as food, but is not regarded as a culinary fruit, nut, herb, spice, or grain. ... Listen to this article ( info/dl) This audio file was created from an article revision dated 2005-07-19, and may not reflect subsequent edits to the article. ... Advanced Micro Devices, Inc. ... This article is about the journal as a written medium. ... The Archives of Ophthalmology is a monthly professional medical journal published by the American Medical Association. ... Kale or Borecole is a form of cabbage (Brassica oleracea Acephala Group), green in color, in which the central leaves do not form a head. ... Trinomial name Brassica rapa rapa L. For similar vegetables also called turnip, see Turnip (disambiguation). ... Greens are people who support some or all of goals of a Green Party without necessarily working with or voting for that or any party. ... Cultivar Group Brassica oleracea Acephala Group Collard or collard greens is a loose-leafed cultivar group of Brassica oleracea Acephala Group, which is grown as a food crop and garden ornamental, mainly in Brazil, United States. ... Romaine lettuce Romaine or Cos lettuce (often called simply Romaine or Cos) (Lactuca sativa L. var. ... Broccoli is a plant of the Cabbage family, Brassicaceae (formerly Cruciferae). ... This article is about the fruit. ... Binomial name L. Corn (Zea mays L. ssp. ... This article needs additional references or sources for verification. ... Binomial name Pisum sativum A pea (Pisum sativum) is the small, edible round green seed which grows in a pod on a leguminous vine, hence why it is called a legume. ... Cultivar Group Brassica oleracea Gemmifera Group The Brussels sprout (Brassica oleracea Gemmifera Group) is a cultivar group of cabbage cultivated for its small (typically 2. ...

Adaptive techniques

A tactile feature on a Canadian banknote.

Visually impaired and blind people have devised a number of techniques that allow them to complete daily activities using their remaining senses. These might include the following: Image File history File linksMetadata Download high-resolution version (871x671, 229 KB) Summary The tactile feature on a Canadian twenty-dollar bill. ... Image File history File linksMetadata Download high-resolution version (871x671, 229 KB) Summary The tactile feature on a Canadian twenty-dollar bill. ... Current Canadian banknotes (the Canadian Journey series) have a tactile feature to indicate denomination in the upper right corner of the face side of the bill. ... Sample Canadian bank notes, $5, $10, $20, $50, $100 Canadian banknotes are the banknotes of Canada, denominated in Canadian dollars (CAD). ...

• Adaptive computer software that allows people with visual impairments to interact with their computer via audio or screen magnifiers.

• Adaptive mobile phones that allows people with visual impairments to interact with their phones via audio or screen magnifiers. These mobile phones uses software called Mobile Speak a screen reader from Code Factory http://www.codefactory.es. It provides audio feedback to every functionality on the phone.
• Adaptations of banknotes so that the value can be determined by touch. For example:
  • In some currencies, such as the euro, and pound sterling, the size of a note increases with its value.
  • Many banknotes from around the world have a tactile feature to indicate denomination in the upper right corner. This tactile feature is a series of raised dots, but it is not standard Braille [5].
  • It is also possible to fold notes in different ways to assist recognition.
• Labeling and tagging clothing and other personal items
• Placing different types of food at different positions on a dinner plate
• Marking controls of household appliances

Most people, once they have been visually impaired for long enough, devise their own adaptive strategies in all areas of personal and professional management. Software redirects here. ... A £20 Bank of England banknote. ... For other uses, see Euro (disambiguation). ... GBP redirects here. ... A £20 Ulster Bank banknote. ... Current Canadian banknotes (the Canadian Journey series) have a tactile feature to indicate denomination in the upper right corner of the face side of the bill. ... Braille code where the word (, French for first) can be read. ...

For corrective surgery of blindness, see acquired vision. Acquired vision is the phenomenon of a blind person gaining the ability to see, usually as a result of medical treatment. ...

Tools

Watch for the blind

Designers, both visually impaired and sighted, have developed a number of tools for use by blind people. Image File history File links Download high resolution version (757x1041, 172 KB) Summary Watch for the. ... Image File history File links Download high resolution version (757x1041, 172 KB) Summary Watch for the. ...

Mobility

Many people with serious visual impairments can travel independently assisted by tactile paving and/or using a white cane with a red tip - the international symbol of blindness. Tactile paving is a system of textured ground surface indicators found on many footpaths and train station platforms to assist blind and vision impared pedestrians. ... A long cane, the primary mobility tool for the visually impaired. ... A symbol, in its basic sense, is a conventional representation of a concept or quantity; i. ...

A long cane is used to extend the user's range of touch sensation, swung in a low sweeping motion across the intended path of travel to detect obstacles. However, some visually impaired persons do not carry these kinds of canes, opting instead for the shorter, lighter identification (ID) cane. Still others require a support cane. The choice depends on the individual's vision, motivation, and other factors.

Each of these is painted white for maximum visibility, and to denote visual impairment on the part of the user. In addition to making rules about who can and cannot use a cane, some governments mandate the right-of-way be given to users of white canes or guide dogs. This article needs additional references or sources for verification. ... A blind man is led by his guide dog in Brasília, Brazil. ...

A small number of people employ guide dogs. The dogs can be trained to navigate various obstacles. The human half of the guide dog team does the directing, based upon skills acquired through previous mobility training. The handler might be likened to an aircraft's navigator, who must know how to get from one place to another, and the dog is the pilot, who gets them there safely. A blind man is led by his guide dog in Brasília, Brazil. ...

Orientation and Mobility Specialist are professionals who are specifically trained to teach people with visual impairments how to travel safely, confidently, and independently in the home and the community.

Reading and magnification

Most visually impaired people who are not totally blind read print, either of a regular size or enlarged by magnification devices. A variety of magnifying glasses, some handheld, and some on desktops, can make reading easier for them. A magnifying glass (called a hand lens in laboratory contexts) is a convex lens which is used to produce a magnified image of an object. ...

The rest read Braille (or the infrequently used Moon type), or rely on talking books and readers or reading machines. They use computers with special hardware such as scanners and refreshable Braille displays as well as software written specifically for the blind, like optical character recognition applications and screen reading software. Braille code where the word (, French for first) can be read. ... The Moon System of Embossed Reading (Moon alphabet, Moon type or Moon code) is a system of writing for the blind, using embossed symbols mostly derived from the Roman alphabet (but simplified). ... A reading machine is a piece of Assistive Technology that allows blind people to access printed materials. ... A refreshable Braille display is an electro-mechanical device for displaying Braille characters, usually by means of raising dots through holes in a flat surface. ...

Some people access these materials through agencies for the blind, such as the National Library Service for the Blind and Physically Handicapped in the United States, the National Library for the Blind or the RNIB in the United Kingdom. The National Library Service for the Blind and Physically Handicapped is a free library program of braille and audio materials circulated to eligible borrowers in the United States by postage-free mail. ... The National Library for the Blind is a public library in the United Kingdom, founded 1882, which aims to ensure that visually impaired people have the same access to library services as sighted people. ... The Royal National Institute for the Blind (RNIB) is a United Kingdom charity, which was set up to lobby for and help people who are blind or partially sighted. ...

Closed-circuit televisions, equipment that enlarges and contrasts textual items, are a more high-tech alternative to traditional magnification devices. So too are modern web browsers, which can increase the size of text on some web pages through browser controls or through user-controlled style sheets. This article refers to a surveillance system. ... High tech refers to technology that is at the cutting-edge—the most advanced technology currently available. ... An example of a Web browser (Mozilla Firefox) A web browser is a software application that enables a user to display and interact with text, images, videos, music and other information typically located on a Web page at a website on the World Wide Web or a local area network. ... Style sheet (desktop publishing) - a feature of desktop publishing programs. ...

Computers

Access technology such as Freedom Scientific's JAWS for Windows screen reading software enable the blind to use mainstream computer applications. Most legally blind people (70% of them across all ages, according to the Seattle Lighthouse for the Blind) do not use computers. Only a small fraction of this population, when compared to the sighted community, have Internet access. This bleak outlook is changing, however, as availability of assistive technology increases, accompanied by concerted efforts to ensure the accessibility of information technology to all potential users, including the blind. Linux distributions (as Live CDs) for the blind include Oralux and Adriane Knoppix, the latter developed in part by Adriane Knopper who has a visual impairment. The Macintosh OS also comes with a built-in screen reader, called VoiceOver. Later versions of Microsoft Windows include an Accessibility Wizard & Magnifier for those with partial vision. Freedom Scientific is a corporation which researches, creates and sells technology to blind people, including software which uses voice synthesizers and the braille code. ... Job Access with Speech (JAWS) is a screen reader for the visually impaired. ... A screen reader is a software application that attempts to identify and interpret what is being displayed on the screen. ... The Seattle Lighthouse for the Blind is a non-profit organization that provides employment, support, and training opportunities for individuals who are blind, Deaf-Blind, and blind with other disabilities. ... This article is about operating systems that use the Linux kernel. ... Gnoppix 0. ... Oralux is an audio GNU/Linux distribution for visually impaired persons. ... Adriane Knoppix is a Knoppix distribution of the Linux PC operating system that is intended for blind and visually impaired people. ... Klaus Knopper (born 1968 in Ingelheim) is a German electrical engineer. ... VoiceOver is a feature built into Apple Computers Mac OS X v10. ... Windows redirects here. ...

The movement towards greater web accessibility is opening a far wider number of websites to adaptive technology, making the web a more inviting place for visually impaired surfers. For Wikipedias accessibility guideline, see Wikipedia:Accessibility. ... Adaptive technology is the name for products which help people who cannot use regular versions of products, primarily people with physical disabilities such as blindness, deafness and inability to walk or use arms. ...

Experimental approaches in sensory substitution are beginning to provide access to arbitrary live views from a camera. Sensory substitution is the principle to transform characteristics of one sensory modality into stimuli of another sensory modality. ... This article is about the photographing device. ...

Other aids

People may use talking thermometers, enlarged or marked oven dials, talking watches, talking clocks, talking scales, talking calculators, talking compasses and other talking equipment. A common mercury thermometer A thermometer is a device that measures temperature or temperature gradient, using a variety of different principles. ... Digital kitchen scales. ... For other uses, see Calculator (disambiguation). ... This article is about the navigational instrument. ...

Social attitudes towards blindness

Moche Portrait of Blind Man. 300 A.D.

The story of the Blind Men and an Elephant uses blindness as a symbol of limited perception and perspective. Stories such as The Cricket on the Hearth by Charles Dickens provided yet another view of blindness, wherein those affected by it were ignorant of their surroundings and easily deceived. H. G. Wells' story The Country of the Blind explores what would happen if a sighted man found himself trapped in a country of blind people to emphasise societies attitude to blind people by turning the situation on its head. Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... The story of the blind men and an elephant appears to have originated in India, but its original source is debated. ... The Cricket on the Hearth is a novella by Charles Dickens, written in 1845. ... Dickens redirects here. ... Herbert George Wells (September 21, 1866 – August 13, 1946), better known as H. G. Wells, was an English writer best known for such science fiction novels as The Time Machine, The War of the Worlds, The Invisible Man, The First Men in the Moon and The Island of Doctor Moreau. ... The Country of Blind is a short story by H. G. Wells. ...

The authors of modern educational materials (see: blindness and education for further reading on that subject), as well as those treating blindness in literature, have worked to paint a different picture of blind people as three-dimensional individuals with a range of abilities, talents, and even character flaws. The practice of institutionalizing the blind in asylums has a history extending back over a thousand years, but it was not until the 18th Century that authorities created actual schools for them. ... Different cultures through history have depicted blindness in a variety of ways; among the Greeks, for example, it was a punishment from the gods, for which the afflicted individual was often granted compensation in the form of artistic genius. ...

The Moche people of ancient Peru depicted the blind in their ceramics.^[13] The Moche civilization (alternately, the Mochica culture, Early Chimu, Pre-Chimu, Proto-Chimu, etc. ...

Young mammals

Statements that certain species of mammals are "born blind" refers to them being born with their eyes closed and their eyelids fused together; the eyes open later. One example is the rabbit. Subclasses & Infraclasses Subclass †Allotheria* Subclass Prototheria Subclass Theria Infraclass †Trituberculata Infraclass Metatheria Infraclass Eutheria Mammals (class Mammalia) are warm-blooded, vertebrate animals characterized by the presence of sweat glands, including milk producing sweat glands, and by the presence of: hair, three middle ear bones used in hearing, and a neocortex... For other uses, see Rabbit (disambiguation). ...

In humans the eyelids are fused for a while before birth, but open again before the normal birth time, but very premature babies are sometimes born with their eyes fused shut, and opening later.

Metaphorical uses

The word "blind" (adjective and verb) is often uses for various types of failing to notice something, for example in this page "For years I [= a gyrfalcon breeder] was impressed and blinded by the white color, but after I bred gyrs for a while I noticed that demand for darker falcons was very strong.". // Binomial name Falco rusticolus Linnaeus, 1758 The Gyrfalcon (Falco rusticolus), also spelled Gyr Falcon (the g is pronounced as j in jar), and also sometimes spelled Gerfalcon, is the largest of all falcon species. ...

"Blind area" can mean an area where someone cannot see, e.g. where a car driver cannot see because parts of his car's bodywork are in the way.

References

The Larco Museum (Spanish: ) is located in the Pueblo Libre District in Lima, Peru. ... Thames & Hudson (also Thames and Hudson and sometimes T&H for brevity) are a publisher, especially of art and illustrated books, founded in 1949 by Walter and Eva Neurath. ...

See also

• Accessibility
• Amaurosis
• Blind musicians
• Blindness and education
• Braille
• Color blindness
• Cortical blindness
• Deafblind
• Inattentional blindness
• List of eye diseases
• Night blindness
• Scotoma
• Snow blindness
• Stereoblindness
• Web accessibility

It has been suggested that Easy Access be merged into this article or section. ... Amaurosis (Greek meaning darkening, dark, or obscure) is vision loss or weakness that occurs without an apparent lesion affecting the eye [1]. It may result from either a medical condition or from excess acceleration, as in flight. ... Blind musicians are singers or instrumentalists who are physically unable to see. ... The practice of institutionalizing the blind in asylums has a history extending back over a thousand years, but it was not until the 18th Century that authorities created actual schools for them. ... Braille code where the word (, French for first) can be read. ... Color blindness in humans is the inability to perceive differences between some or all colors that other people can distinguish. ... Cortical blindness is the total or partial loss of vision in a normal-appearing eye caused by damage to the visual area in the brains occipital cortex. ... Deafblindness (or deaf-blindness) is the condition of a person who is both deaf and blind. ... Inattentional blindness, Also known as perceptual blindness which is the phenomenon of not being able to see things that are actually there. ... This is a list of eye diseases. ... Nyctalopia (literally night blindness) is a condition making it difficult or impossible to see in the dark. ... The word scotoma is derived from the Greek word for darkness. ... For other meanings see Snowblind. ... Stereoblindness (also stereo blindness) is the inability to see in 3D using stereo vision, resulting in the sufferers inability to perceive stereoscopic depth. ... For Wikipedias accessibility guideline, see Wikipedia:Accessibility. ...

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• http://www.direct.gov.uk/disability Directgov disabled people - UK govt information
• Access Watch: Blind users review accessibility of mainstream software
• The Chicago Lighthouse for People Who Are Blind or Visually Impaired
• AccessWorld Technology and People Who Are Blind or Visually Impaired
• American Council of the Blind
• American Foundation for the Blind
• Blind Access Journal: Visual impairment in the real world
• Christian Blind Mission
• VISION 2020: The Right to Sight
• International Agency for the Prevention of Blindness (IAPB)
• International Braille Research Center
• Journal of Visual Impairment & Blindness
• Literature Bibliography and Resources List
• National Braille Press
• National Federation of the Blind: Civil rights and consumer advocacy
• National Library for the Blind
• National Library Service for the Blind and Physically Handicapped
• Recording for the Blind and Dyslexic
• Royal National Institute for the Blind
• Scottish Sensory Centre
• SMCCB Vision Links
• WHO Fact Sheet on Visual Impairment
• Catalan Association for the Blind and Visually Impaired