Why An Eye Chart Is Not Enough

There are several situations in life where one's sight is critical. Driving a car is one such. Working at virtually any job is another. Even tasks as simple as walking across one's own floor are made simpler by adequate ability to see obstacles. Testing sight has been done for years with an eye chart. However, this method is far from adequate.

Many conditions can affect how one is able to see. One such condition is known as tunnel vision. Individuals suffering from this condition can see perfectly within a well defined zone directly in front of them. However, they have little or no peripheral sight. This can adversely affect one's ability to operate equipment, including motor vehicles.

Color blindness is a condition that affects men. Those with this condition cannot typically distinguish red or green colors. While this is normally a minor inconvenience, there are times when it can be critical. An example would be in quickly distinguishing between a start button and an emergency stop on an industrial machine.

A medical condition that affects sight is dyslexia. Those with this condition often see words and letters in jumbled order. This can make reading difficult as well as make it difficult to distinguish between the letter E and the number 3 in block writing. A standard eye chart does not test for this condition.

Given the number of conditions that affect the eyes and the way people see, it is imperative to know more about how they see than at what distance they are able to read a line of letters on a chart. 20/20 vision is the accepted standard, meaning that the person can see at 20 feet what he or she should be able to see. However, this is not an accurate assessment tool.

Most medical professionals make use of a vision tester that is capable of checking for each of the various conditions that can limit or affect one's ability to see. While some conditions, such as nearsightedness or farsightedness, can be treated with glasses or contacts, other conditions exist that can limit the types of work a person is able to perform or equipment he/she is able to operate. This device can even check for simple eye strain, a common affliction among those who spend entire days staring at a computer monitor. It is a much more thorough diagnostic tool than the old fashioned eye chart seen on the walls at most doctor's offices.