• size
  • In photography, the size of the entrance pupil (rather than the size of the physical aperture itself) is used to calibrate the opening and closing of the diaphragm aperture . (wikipedia.org)
  • Similar to the eyes of other mammals, the human eye's non-image-forming photosensitive ganglion cells in the retina receive light signals which affect adjustment of the size of the pupil, regulation and suppression of the hormone melatonin and entrainment of the body clock. (wikipedia.org)
  • The size of the pupil, which controls the amount of light entering the eye, is adjusted by the iris' dilator and sphincter muscles. (wikipedia.org)
  • As soon as the eye moves rapidly to acquire a target (saccades), it re-adjusts its exposure by adjusting the iris, which adjusts the size of the pupil. (wikipedia.org)
  • Another consequence of this design is that the entrance pupil varies in size during the tracking of a target. (wikipedia.org)