What is the purpose of single vision lenses?

Single vision lenses are specifically designed to correct vision at one specific focal length. This means that they are intended for use by individuals whose vision correction needs fall into a singular category, such as nearsightedness (myopia) or farsightedness (hyperopia). For example, someone who struggles to see clearly at a distance may use single vision lenses to correct their distance vision, while an individual who has trouble with close work can use them for reading or other near tasks.

The clarity and focus provided by single vision lenses make them effective for individuals who do not have a complex vision prescription requiring different lens powers for various distances. This focus on one focal length is what distinguishes single vision lenses from other types of lenses, such as bifocals or progressives, which accommodate multiple focal lengths.

The other answer choices refer to functions that aren't relevant to what single vision lenses provide. Bifocals and progressive lenses would be more appropriate for those needing corrections for more than one focal distance. Similarly, enhancing peripheral vision or providing tint variation would apply to different types of lenses, not the focus mechanism of single vision lenses.