Dome magnifier

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A rendered image showing a dome magnifier over a page of text. Dome magnifier rendered.jpg
A rendered image showing a dome magnifier over a page of text.

A dome magnifier is a dome-shaped magnifying device made of glass or acrylic plastic, used to enlarge words on a page or computer screen. They are plano-convex lenses: the flat (planar) surface is placed on the object to be magnified, and the convex (dome) surface provides the enlargement. They usually provide between 1.8× and 6× magnification. [1] [2] Dome magnifiers are often used by the visually impaired. They are good for reading maps or basic text and their inherent 180° design naturally amplifies illumination from ambient side-light. They are suitable for people with tremors or impaired motor skills, because they are held in contact with the page during use. [1]

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References

  1. 1 2 Albert, Daniel M.; Jakobiec, Frederick A. (2000). Principles and practice of ophthalmology (2. ed.). Philadelphia: Saunders. p. 5433. ISBN   9780721675060.
  2. Assistive Devices for Reading Issue 93, Part 2 of Reference circular. National Library Service for the Blind and Physically Handicapped, The Library of Congress. 1993.