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.
Night-vision glasses work by capturing tiny amounts of light, some of it from the infrared portion of the light spectrum, and amplifying it in order to create an image that is more easily observed. Some systems may also utilize thermal imaging technology, either alone or in concert with light amplif
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
According to MedlinePlus, a visual acuity measurement of 20/25 is only slightly worse than average. What "20/25" basically means is that a person's eye can see at 25 feet what a typical eye can see at 20 feet.
In optometry, 20/15 vision is considered to be above average in terms of eye sight. By most metrics, 20/15 is the best vision rating that a person can receive and is even better than 20/20 vision.
A person with 20/15 vision can see an object from 20 feet away with the same acuity as a normal person would at 15 feet away. Technically, then, a person with 20/15 vision has better than perfect vision.
According to How Stuff Works, 20/20 vision means that a person can see what a normal person can see when standing 20 feet away. A person with 20/13 vision is above average because it means he can see at 20 feet what a normal person can see at 13 feet.
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.
Common vision symptoms include blurred vision, flashing lights, floaters and an inability to distinguish between colors, according to WebMD. Additional symptoms include difficulty with vision tests and uncoordinated movement of the eyes.
Reviews for night vision glasses can be found on retail sites like Amazon, Target, and As Seen on TV. Reviews are typically left on an individual product's listing page within a specific website, and offer detailed information and feedback on other customers' experiences with the product.