In optical terms, the anatomical pupil is the eye's aperture and the iris is the aperture stop. The image of the pupil as seen from outside the eye is the entrance pupil, which does not exactly …

Miosis (small pupil): The medical name for very small pupils (constricted) is miosis. Small pupils can happen when you’ve had a stroke or when you’ve used opiates, among other reasons.

4 days ago · A pupil is the opening created by the iris, which controls the amount of light that enters the eye. Learn about medical conditions affecting the pupils.

Dec 4, 2024 · Pupils are the dark-colored openings at the center of your eyes that let light in. Doctors can look at your pupils for clues about your health. The size of your pupils and how …

Jul 6, 2023 · Learn about the dark openings at the center of your eyes called pupils, how they react to light, and what changes in pupil size and shape can indicate about your health.

Dec 29, 2025 · The amount of light entering the eye is restricted by the aperture in the iris, the pupil. In a dark room, a person’s pupils are large, perhaps 8 mm (0.3 inch) or more in …

Feb 26, 2019 · Typically, the pupils appear perfectly round, equal in size and black in color. The black color is because light that passes through the pupil is absorbed by the retina and is not …

1 day ago · Discover everything about the pupil of the eye: structure, function, light response, and what pupil changes reveal about your health. Expert guide to understanding this vital part of …

The human pupil is typically round in shape, but in some animals, the shape can vary (for example, cats have slit-shaped pupils). The round shape ensures that light is evenly …

Mar 4, 2025 · The pupils are the parts of the eye that constrict and dilate in response to light, controlled by the iris. Pupil-related eye conditions include anisocoria, cataracts, miosis and …