- The process by which the iris and the retina of the eye adjust to allow maximum vision in dim illumination following exposure of the eye to a relatively brighter illumination. In darkness, vision becomes more sensitive to light, provided a person has not been exposed to bright light for some time. Although exposure to total darkness for at least 30 minutes is required for complete dark adaptation, a pilot can achieve a moderate degree within 20 minutes under dim red cockpit lighting. Dark adaptation is impaired by exposure to cabin pressure altitudes above 5000 ft, carbon monoxide inhaled in smoking and from exhaust fumes, deficiency of vitamin A in the diet, and prolonged exposure to bright sunlight.
Aviation dictionary. 2014.
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dark adaptation — därk n the phenomena including dilation of the pupil, increase in retinal sensitivity, shift of the region of maximum luminosity toward the blue, and regeneration of rhodopsin by which the eye adapts to conditions of reduced illumination compare … Medical dictionary
dark adaptation — n. the adaptation of the eye to vision in the dark by dilation of the pupil, increased sensitivity of the retina, etc. dark adapted adj … English World dictionary
dark adaptation — the changes that take place in the retina and pupil of the eye enabling vision in very dim light. Dark adaptation involves activation of the rods – the cells of the retina that function best in dim light – and the reflex enlargement of the pupil… … The new mediacal dictionary
dark adaptation — prisitaikymas prie tamsos statusas T sritis fizika atitikmenys: angl. dark adaptation vok. Dunkeladaptation, f rus. темновая адаптация, f pranc. adaptation à l’obscurité, f … Fizikos terminų žodynas
dark adaptation — dark adapted, adj. Ophthalm. 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… … Universalium
dark adaptation — dark′ adapta tion n. oph the reflex adjustment of the eye to dim light or darkness, consisting of a dilation of the pupil, an increase in the number of functioning rods, and a decrease in the number of functioning cones • Etymology: 1905–10 dark′ … From formal English to slang
dark adaptation — /ˈdak ˌædæpteɪʃən/ (say dahk .adaptayshuhn) noun the reflex response of the eye to a diminution of light, comprising the dilation of the iris and an increase in the number of functioning rods with a corresponding decrease in the number of… … Australian English dictionary
dark adaptation — A change in the retina of the eye sensitizing it to dim light (the eye “becomes accustomed to the dark”) . Compare light adaptation … Lexicon of Cave and Karst Terminology
dark adaptation — noun the process of adjusting the eyes to low levels of illumination; cones adapt first; rods continue to adapt for up to four hours • Hypernyms: ↑adaptation … Useful english dictionary
dark adaptation — noun Date: 1900 the process including dilation of the pupil, increase in sensitivity of the retinal rods, and regeneration of rhodopsin by which the eye adapts to conditions of reduced illumination • dark adapted adjective … New Collegiate Dictionary