Spherical aberration occurs when light rays passing through a lens or reflecting off a mirror do not converge at a single point. This happens because spherical surfaces, like those found in many lenses and mirrors, cause light rays that strike the edges to focus at different points than those that hit the center. As a result, images can appear blurry or distorted. This optical issue is common in devices such as cameras, telescopes, and microscopes. To minimize spherical aberration, designers often use aspheric lenses or special coatings, which help ensure that light rays focus more accurately, improving image clarity and sharpness.