By Definition, Blindness is the condition of lacking visual perception due to physiological or neurological factors.
Various scales have been developed to describe the extent of vision loss and define "blindness." Total blindness is the complete lack of form and visual light perception and is clinically recorded as "NLP," an abbreviation for "no light perception." Blindness is frequently used to describe severe visual impairment with residual vision. Those described as having only "light perception" have no more sight than the ability to tell light from dark. A person with only "light projection" can tell the general direction of a light source.
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. 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 (6.1 m) from an object to see it—with vision correction—with the same degree of clarity as a normally sighted person could from 200 feet (61 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.
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.
It should be noted that blind people with undamaged eyes may still register light non-visually for the purpose of circadian entrainment to the 24-hour light/dark cycle. Light signals for this purpose travel through the retinohypothalamic tract (RHT), so a damaged optic nerve beyond where the RHT exits it is no hindrance." (Wikipedia.com)
There are two types of drawing boards for the blind. Every blind child or adult attending an art class or learning to draw should have one of the two types:
|Blind students can also explore thermoform plastic|
pages that include both raised pictures and braille.
Tactile surfaces such as these, provide even more opportunities
for blind students to experience the art of illustration.
|A thermoform page illustrating the scripture and a lion.|
|One of thirteen thermoform plastic pages I created|
for a Christian calendar. This one is of a man
in the belly of a fish. These unique calendars for
the blind may be purchased through Lutheran Blind Missions.
All of the proceeds help support their mission
to teach the blind about the love of Christ.
Articles about teaching art to the blind:
- Blind children in UK experience Olympics through sound, touch
- About Art Education for the Blind
- Artist uses ceramics as medium to link sighted, non-sighted individuals
- Accessibility Art Education For The Blind at the Cummer Museum
- The Blind Child In The Regular Elementary Classroom
- Art Beyond Sight Awareness Month
- Technology to help blind students in regular-ed classrooms
- This was no art lesson
- About Art Education for The Blind
- A lesson I wrote for teaching blind students to differentiate between abstract and realistic portraiture