Definition Of Visual Impairment / Blindness
The first possible is between correct corrective and non-correctable visual impairments. The correctable farsightedness, myopia – can be largely repaired with glasses or contact lenses.
Non-correctable visual damage is usually congenital or caused by an accident and affects disorders in the optic nerve, the present invention is a visually impaired student.
And the visually impaired people still wear glasses, suggesting a combination of correctable and non-correctable visual impairments. Despite his or her glasses, can only achieve visual acuity values such as described below.
As visually impaired applies, who is not achieved despite normal correction and its visual acuity in the distance and / or near to 1/3 (30%) to 1/20 (5%) is reduced to the standard (100%).
This means that a visually impaired person with 1/20 eyesight can detect what a normal sight sees from a distance of 20 feet from a distance of 20 feet.
Those with a high degree of vision impairment are those who have a reduction from 1/20 (5%) to 1/50 (2%) of the standard (100%). These values cannot be improved with glasses or contact Lens.
Blindness is when the eyesight is so greatly reduced that the affected cannot behave like sighted even after optical correction. Students who have to expect blindness are to be treated in in terms of special educational needs.
Every person with visual impairment has a different severity of visual impairment.
It is very important, especially in the school sector, to examine the individual viewing behavior of the individual student under everyday conditions – lighting conditions in the classroom, distances from the board, etc.
For example, a significant difference can be observed between near vision and long range vision.
The visual performance is influenced by the physical and mental state of the individual, by the time of day, by brightness, contrast, color and much more
What the visually impaired can see depends not only on medically measurable values; Factors such as education, experience, intelligence, and motivation can affect vision.
Due to these factors, the visually impaired person can more or less compensate for Hyperopia Definition Or Longsightedness or visual impairment.
In order to be able to determine all these values and prerequisites, in the case of visually impaired pupils – in addition to the important medical test at the ophthalmologist –
A test is carried out on the functional vision of the pupil at school or at the visually impaired pedagogue determines the sight, as it is used individually in everyday life, through observations and with various eye tests.