Illinois Vision Certification Practice Test

Which refractive error is corrected with convex lenses?

1. Myopia

2. Astigmatism

3. Hyperopia

4. Presbyopia

The correct answer is: Hyperopia

Convex lenses are used to correct hyperopia, commonly known as farsightedness. In hyperopia, distant objects may be seen clearly, but nearby objects appear blurry because the light entering the eye focuses behind the retina instead of directly on it. Convex lenses are thicker in the middle and help to converge light rays before they enter the eye, effectively moving the focus point forward onto the retina. This adjustment enables the individual to see nearby objects more clearly. While myopia (nearsightedness) requires concave lenses to diverge light rays and move the focal point back onto the retina, astigmatism involves an irregular curvature of the cornea or lens that causes distorted vision and is typically corrected with cylindrical lenses rather than simple convex ones. Presbyopia, which is often associated with aging, can also be treated with reading glasses that sometimes use convex lenses, but it is a specific condition rather than a refractive error typically addressed solely by convex lenses. Thus, the primary association of convex lenses is with the correction of hyperopia.