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PubMed · 907025

Telescopes, light vergence, and accommodation.

A N Freid
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Abstract

This paper explains why the accommodative response to near objects is ineffective through a telescope. A simple formula is used to demonstrate the need for a bifocal spectacle objective or a change in vertex distance when viewing near objects with a contact lens spectacle lens telescope. Using this exact formula, clinicians can now more precisely compare refractions with and withoug a telescope. The formula also shows why refractions with telescopes used for driving should be accomplished at test distances of 20 feet or more.

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Accommodation, OcularHumansLensesMathematicsRefraction, OcularJournal Article

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A N Freid. 1977. Telescopes, light vergence, and accommodation.. https://doi.org/10.1097/00006324-197706000-00004

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