Myopia is always corrected using which type of power?

Myopia, commonly known as nearsightedness, is a visual condition where close objects can be seen clearly, but distant objects appear blurry. The underlying problem in myopia is that light rays entering the eye are focused in front of the retina, rather than directly on it. To correct this condition, lenses that diverge light rays are used.

Minus power lenses are designed to spread light rays apart, allowing the focal point to move further back into the eye, aligning it correctly with the retina. By using minus power, the correction enables patients with myopia to see distant objects more clearly.

In contrast, plus power lenses are used for hyperopia (farsightedness), where light needs to be focused more closely to the eye. Cylinder power is used to correct astigmatism, which involves the curvature of the cornea, while axis refers to the orientation of astigmatism correction, not the power itself. Understanding these differences is crucial for effective lens prescribing and patient vision correction.