Anatomy and physiology of the eye, with hints for the preservation of the eyesight (1901)
Herbert, John Frederick, 1860- · Philadelphia, Pa., The author · leaf 40
the con- 34 dition may be acquired. On account of the asymmetry ofthe refracting surfaces, it produces a distorted image onthe retina, which disturbs and diminishes the acuity ofvision according to the degree of the defect. Both distantand near vision are equally affected, since at no pointcan a… … Figure 21.Chart illustrating appearance of disc in astigmatism. c\nother distinguishing feature of this defect is the factthat certain groups in a series of lines, such as representedin figure 20, are seen with more distinctness and appearblacker than those that are situated in the opposite…
Eye · Lenses
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