Home Made Eye Charts
With little effort and some easy to find tools, you will be able to conduct an Eye Chart test at home. Read more on how to get your test area prepared in your own home.
Many people suffer from some kind of visual impairment. In some cases, their vision may only be partially affected, while in others, it is completely lost. People who are blind are said to have a vision of 20/400 or even less than that. Occasionally illness or trauma can bring on visual impairment. People who have low vision typically have trouble seeing things that are either close or far. Vision loss usually cannot be helped with corrective lenses. However, some cases can be remedied with surgery or prescription medication.
How Common is Visual Impairment?
Recent statistics indicate that out of around three hundred million people around the world who are visually impaired, approximately forty five million are considered totally blind. Well over three-thirds of visually impaired people are in developing nations and in most of their cases, the impairment could have been avoided. Comparatively, these rates are much lower in North America and Europe. Visual impairment tends to strike a large portion of senior citizens, and the risk increases as they age, especially in older women. Internationally, only around eight percent of males develop color blindness, a hereditary trait, as opposed to the miniscule one percent of women. In just over a third of visual impairment victims, the cause is due to cataracts, while refractive error is the next most common cause.
Classifications of Visual Impairment
There are three main types of blindness. In order of seeing ability, they are low vision, legal blindness, and total blindness. People with low vision have moderate to low eyesight. In comparison, those who are legally blind are unable to see very large objects or text even while wearing lenses. Finally, total blindness is when all sight is nonexistent. Those who are colorblind or suffer from snow blindness or night blindness can usually see quite clearly, except under certain specific conditions.
What Causes Blindness?
As people grow older, they may develop illnesses like glaucoma, diabetes, cataracts, and macular degeneration, which in turn cause blindness. In younger people, eye injury is a common factor that contributes to blindness. Brain injuries, along with illnesses at birth or overexposure to certain chemicals like methanol can also bring on blindness. Unnatural causes of blindness include torture, acid attacks, and other gross acts that are meant to harm a person.
Techniques and Tools to Adapt
Unlike older times when visually impaired people were at a loss, there are plenty of solutions today that allow them to function as normally as possible. They can be mobile by walking with a cane as well as a trained guide dog and GPS devices. Reading and learning is achieved not only with printed Braille pages, but also with accessible web pages and software, voice recognition systems, and Braille keyboards. These types of technologies not only allow visually impaired people to catch up with those with normal sight, but to even surpass them.