AAMC FL Practice Exam

What type of lens is used to correct myopia?

1. Diverging concave lens

2. Converging convex lens

3. Flat lens

4. Cylindrical lens

The correct answer is: Diverging concave lens

Myopia, commonly known as nearsightedness, occurs when the eye is too long relative to its optical power, causing distant objects to appear blurry while nearby objects can be seen clearly. To correct this condition, a diverging lens, typically a concave lens, is employed. A diverging concave lens spreads light rays outward, effectively increasing the focal length of light entering the eye. This allows the image of distant objects to be focused further back in the eye, onto the retina. By doing this, the correct lens helps those with myopia see distant objects more clearly. In contrast, a converging convex lens, which causes light rays to converge, would not correct myopia; instead, it would exacerbate the issue by causing these rays to focus in front of the retina. Flat lenses have no refractive power and do not address vision issues. Cylindrical lenses, on the other hand, are specifically used to correct astigmatism, which is caused by an irregular curvature of the cornea or lens, rather than myopia.