Visual acuity (VA).

Visual acuity is how well one can see details. It is one of several factors in vision, including color vision, depth perception, and peripheral vision and part of a comprehensive eye exam. Visual acuity tests are used to determine how well one sees details of a symbol or letter from a specific distance. The tests may be performed by optometrists, ophthalmologists, opticians, technicians, family doctors, or nurses, depending on the type and purpose of test.