单词	fovea
释义	fovea /ˈfəʊvɪə / (also fovea centralis) noun (plural foveae /ˈfəʊvɪiː/) Anatomy A small depression in the retina of the eye where visual acuity is highest. The centre of the field of vision is focused in this region, where retinal cones are particularly concentrated.When we gaze directly at an object, we hold our eyes in such a position that the image of the object falls on the central, specialized region of the retina - the fovea or macula - where visual acuity and colour vision are best.... The fovea creates the most finely detailed vision for such daily tasks as reading, threading a needle, or driving a car. The cones are concentrated in the center of the back of the eye, at its most sensitive region, called the fovea. Derivatives foveal adjective ... Ophthalmologic examination with the slit lamp demonstrates the iris pigment defect, as well as retinal hypopigmentation and foveal hypoplasia. After a few months most of them had recovered fully, but six were left with faint shadows in their central vision corresponding to a small foveal burn. A plane visible in the foveal field from 5,000 feet would only be visible at 500 feet or less if it's more than five degrees on either side of the foveal field - hardly enough room to take evasive action. foveate /-vɪeɪt/ adjective Origin Late 17th century: from Latin, literally 'small pit'.
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