The round hole in the centre of the iris that corresponds to the lens aperture in a camera The pupil varies in size according to whether the environment is bright (small pupil) or dark (large pupil)
The black empty space located at the center of the eye A normal pupil will shrink when a light is directed into it and should enlarge in the dark The pupil should also constrict or shrink when focused on a near object This is controlled by muscles located in the iris
the center hole in the iris through which light must pass to reach the back of the eye
Appears as a small black dot in the center of the iris The pupil changes its diameter in response to changes in ambient lighting The pupil varies the amount of light reaching the retina and the depth of focus of the eye
The pupil is the opening in the middle of the iris It functions like the diaphragm in a camera, controlling the amount of light that enters the eye The pupil is small in bright light and large in dim light
A 2/3 pupil stop used to block the portion of the wavefront originating from the outer 1/3 of the HST primary mirror, reducing the deleterious effects of spherical aberration
a hole in the center of the iris that changes size in response to changes in lighting It gets larger in dim lighting conditions and gets smaller in brighter lighting conditions