| the reflex adaptation of the eye to dim light, consisting of a dilatation of the pupil and an increase in the number of functioning rods accompanied by a decrease in the number of functioning cones (opposed to light adaptation ). |
| dark adaptation n. The physical and chemical adjustments of the eye, including dilation of the pupil and increased activity of rods in the retina, that make vision possible in relative darkness. dark'-a·dapt' (därk'ə-dāpt') v., dark'-a·dapt'ed (därk'ə-dāp'tĭd) adj. |
dark adaptation n.
The adjustment of the eye under reduced illumination, in which sensitivity to light is greatly increased. Also called scotopic adaptation.
