How do glasses work on a person?

Refraction: When light moves from the air through the lens, it bends. This bending of light is called refraction. The amount of refraction can be controlled by the curvature and material of the lens. When people need glasses it is because light is not focusing on their retina. Using the refractive power of glasses we can focus light onto the retina in order to form a clear image.

Glasses: Glasses work by focusing light onto the center of the retina (which is the part of the eye that sees). Without glasses, many individuals eyes do not focus the light in the correct location.