Which type of lens is used to correct myopia?

Myopia, or nearsightedness, is a common refractive error where distant objects appear blurry while close objects can be seen clearly. This condition occurs when the eye is either too long, relative to its optical power, or when the cornea has too much curvature, causing light rays to focus in front of the retina rather than directly on it.

To correct myopia, a minus lens is used. Minus lenses are concave in shape, meaning they are thinner at the center compared to the edges. When light passes through a minus lens, it diverges, which helps to move the focal point back onto the retina. By using a minus lens, the light rays entering the eye are spread out slightly, allowing for the proper focusing of images from distant objects on the retina, thereby improving visual clarity.

The other types of lenses mentioned serve different purposes. Plus lenses are used to correct hyperopia (farsightedness), cylindrical lenses are designed to correct astigmatism by compensating for irregular curvature of the cornea or lens, and bifocal lenses address both nearsightedness and farsightedness by incorporating two different lens powers in one. Understanding the specific use of different lens types is crucial in optometry and opticianry to