Refraction of the eye : its diagnosis and the correction of its errors / by A. Stanford Morton.

  • Morton, A. Stanford.
Date:
1897
Catalogue details

Licence: Public Domain Mark

Credit: Refraction of the eye : its diagnosis and the correction of its errors / by A. Stanford Morton. Source: Wellcome Collection.

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    of light in the same manner as a spherical, but acts most on those proceeding in a direction at right angles to its axis. [g) By the refraction of a lens is meant the property which it possesses of altering the direction of rays tra- versing it. (h) The refracting power of a lens is indicated by the dis- tance from it of the point at which parallel rays traversing it meet, i.e., by its focal distance. The greater the focal distance, the less is its refracting power, and vice versa.