What kind of lens is typically used to correct nearsightedness?

Nearsightedness, also known as myopia, occurs when the eye is too long relative to the focusing power of the cornea and lens, causing distant objects to appear blurry while close objects can be seen clearly. To correct nearsightedness, a concave lens is used.

A concave lens is specifically designed to diverge light rays before they reach the eye, effectively allowing the image to be focused on the retina rather than in front of it. By doing so, it helps individuals with myopia to see distant objects more clearly.

The other types of lenses mentioned serve different purposes; for instance, bifocal lenses are intended for individuals who need correction for both distance and near vision, convex lenses are generally used to correct farsightedness (hyperopia) by converging light rays, and prism lenses are used to address issues with eye alignment and focus rather than refractive errors like myopia. Thus, the most suitable choice for correcting nearsightedness is indeed the concave lens.