Contact lenses are thin, curved lenses that are placed directly on the eye's surface to correct vision. They are an alternative to traditional eyeglasses and can be used to correct various vision problems.
Focal length is the distance between the center of a lens and its focal point. It is an important factor in determining the strength and effectiveness of a lens.
The focal length of a lens determines how much the light rays are bent as they pass through the lens. This, in turn, affects the focus of the image on the retina, and therefore, the clarity of vision.
The uncorrected far point distance is the maximum distance at which a person with normal vision can see clearly without the use of corrective lenses. It is usually around 20 feet for adults.
Contact lenses work by changing the focal length of the eye. By placing a corrective lens on the eye, the focal length is altered, allowing for clearer vision at various distances, including the uncorrected far point distance.