Which condition involves unequal refractive power in the eye?

The condition that involves unequal refractive power in the eye is astigmatism. This occurs when the cornea or lens has an irregular shape, causing light rays to be refracted differently in various meridians. As a result, images may be blurry or distorted because the light entering the eye does not come to a single point of focus on the retina.

Astigmatism can lead to difficulties in clearly seeing both near and far objects due to this uneven refraction. Treatment typically includes corrective eyeglasses or contact lenses designed to compensate for the uneven curvature, allowing for clearer vision. Understanding this condition is key in the field of optometry and ophthalmology, as it directly affects how vision is perceived and corrected.

Looking at the other options, hyperopia (farsightedness) and myopia (nearsightedness) involve uniform changes in refraction where light focuses either behind or in front of the retina, respectively. Anisometropia refers to a condition where there is a difference in refractive power between the two eyes, but it does not specifically denote the irregular curvature of the cornea or lens characteristic of astigmatism. Therefore, astigmatism is the correct answer for the condition characterized by unequal