HISTORICAL PERSPECTIVE ON THE FAR POINT IN HYPERMETROPIA
By C. H. BROWN, M. D. 1921

In emmetropia the far point of distinct vision is situated at infinity, or at any distance far enough removed from the eye that the rays proceeding from it shall be parallel.

While in hypermetropia, on account of the adaptation of the eye for the unnatural convergent rays, the far point is negative, or may be said to be situated beyond infinity, if such a condition can be imagined.

In emmetropia the parallel rays are united on the retina, and distinct vision is the result; in hypermetropia these same parallel rays strike the retina before they have converged to a focal point, which renders distinct vision an impossibility, because each point of the image is surrounded by diffusion circles, and these circles from points of the image close together overlap each other.

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