Dilated pupils (mydriasis or fixed pupils) are when your eyes' pupils, which let light into your eyes, become wider. This can ...

Medically reviewed by Johnstone M. Kim, MD Key Takeaways The pupil controls how much light enters the eye, allowing for clear ...

The iris is a structure behind the transparent cornea of the eye. It has a circular opening called the pupil that changes size in response to the light level. Your pupils are usually the same size as ...

The creation of a bionic eye that mimics the widening and shrinking of the pupil may bring us one step closer towards helping people with certain visual impairments. Light enters the eye via the pupil ...