Do You Know the Standard and the Various 7 Levels of Visual Disability Scale
But if the reading material is held little closer to face then the person can comfortably read the material provided the light source is bright.
In majority of the states, the law permits persons with a visual acuity level of 20/60 to drive vehicles and there are certain restrictions for such persons in getting driving licenses.
Many people can use telescopic glasses that can aid in better driving and such people can apply for licenses if there are no restrictions put forth by the states.
People who come under this category of vision range will not have any vision loss and they will still possess an excellent travel and object vision.
This particular range of vision is considered as mildly impaired. People who are in this range will begin to feel the inconvenience in real sense and will start brooding over the handicap.
Persons will have real difficulty in reading magazines and newspapers and the situation will be worse in poor light conditions.
As persons may need little magnification for reading, many states even consider this as a disqualification and refuse to issue with any driving licenses for such persons.
However, there are few states which still issue driving licenses for such persons provided they are equipped with telescopic glasses. Travel and object vision for such persons will still continue to be excellent except for persons who have lost field vision.
20/75 to 20/200
This vision range is the starting point, which is considered as moderately, impaired and persons belonging to this group can still lead a normal life with the help of certain low-vision aids.
Though the object related vision is poor for this group of persons, the vision range can still be considered as adequate for almost all activities.
The persons coming under this category of vision range may be able to identify the moving vehicles such as cars but cannot make the model or the make of such cars.
They also find difficulty in recognizing their friends faces from a distance and they can take up travel provided there is no loss of field vision.
The primary problem faced by such persons is the reading but a vision enhancing aid can help in undeterred reading. Even a low-end vision aid can be used by these persons for good reading and with telescopic glasses they can even drive comfortably provided there are no serious peripheral-vision loss.
20/200 to 20/800
Persons coming under this vision range are considered as seriously impaired, but may possess a manageable travel vision and a useful reduced object vision.
With the assistance of low-vision aids, these persons can read all kinds of reading materials and those who fall under below 20/500 mark may find it difficult to read even with external aids.
These people are not fit for driving even with the assistance of telescopic glasses.
They may till posses an useful object vision, but the travel vision is not adequate enough for driving and hence many states refuse to issue.
Such persons with license especially for people who come under the lower end of the range. Identifying people falling under this category will be easy, as these people will have difficulty while crossing roads, as they are not able to see vehicles coming at a distance.
20/800 to 20/1200
This range of vision is the severely impaired range and persons coming under this category will be totally unfit for driving due to the loss of travel vision.
Further, if the person who comes under this category happens to suffer from peripheral vision loss also, then it is better for such person to carry a white cane meant for visually handicapped persons.
The affected person will be in need of a good magnifying glass even for reading bigger letters or any larger prints, and a lens with a +50 diopter refractive power will be necessary for reading any normal sized texts found in text books.
20/1200 to 20/6000
Severely vision impaired person will fall under this category of vision range. Many doctors have even got reservations in using this visual acuity figures and persons coming under this category will not be able to read letters below a size of 700 from a reading chart.
These persons can only identify a moving hand at a distance of one foot, but they cannot even identify the finger details in the hand and such is the severity of this visual acuity.
Normally persons falling under this 20/1200 to 20/6000 group need to depend either on a guide dog or a white cane for their regular and independent mobility.
These people have ability only to see a video based reading material and any voice based print can also assist such people in knowing the activities that are going around them.
The object vision is also very little for this category of people and they are able to identify things only with the associated light perception.
For instance, the person who falls under this category of vision range, can identify the presence of two persons or objects only with the passing light beam between these two objects or persons.
the person cannot make out the difference between the persons or objects
and what all he knows is that whether the space between two objects is
sufficient enough for him to pass through or not