Someone with "20/30 vision" stands 20 feet from a reading chart but sees letters and objects that people with normal vision see 30 feet away from the chart, according to the University of Iowa. The first number, 20, is the distance from the eye chart and the second number, 30, shows the size of the letters read at that distance.Know More
A patient with 20/30 vision may need corrective lenses to see properly. The University of Iowa also explains that about 35 percent of Americans have 20/20 vision, meaning they see things normally. Having 20/20 vision describes someone who has sharp, clear vision at a distance. The American Optometric Association explains that other factors including depth perception, peripheral vision and color discernment determine a person's overall seeing ability.
The ability to see from a certain distance is measured by an eye chart hanging on a wall. The chart has 11 rows of letters, with a large "E" at the top. A patient able to read the "E" and nothing else on the chart has 20/200 vision, according to All About Vision. Having 20/200 vision is the definition of legal blindness in the United States. Drivers of vehicles need to have at least 20/40 visual acuity with corrective lenses. The line of 20/20 vision is the fourth row from the bottom of the chart. If a person can read the very bottom line of the chart, that person has 20/5 vision.Learn more in Vision
A person with 20/30 vision probably doesn't need glasses, according to EyeCare of East Texas. A determination of 20/30 acuity means that a person sees at 30 feet away from an object what average people see at 20 feet away.Full Answer >
In humans, perfect vision is a visual acuity of 20/20. The first number in 20/20 refers to the distance at which a person can see a particular object in daylight; the second number refers to the distance a human eye with perfect vision can see the object.Full Answer >
According to WebMD, blurry vision may stem from a number of sources, including an eye injury, nearsightedness or allergies. Hay fever and indoor allergens may also cause blurriness in the vision. Dry eye, pink eye and foreign objects in the eye also cause blurriness.Full Answer >
A person with 20/25 vision can stand 20 feet from an eye chart and see the same detail as a person who has 20/20 vision that stands 25 feet from the same chart, according to Divyesh Eye Hospital. The term "20/25 vision" is used to describe the quality of a person's vision compared to someone with 20/20 vision, which is considered “normal” or “average” vision.Full Answer >