Phone: 800-410-1618

1557 Gehman Road
Harleysville, PA 19438
Phone: 267-203-8665
Toll Free: 800-410-1618
Fax: 800-468-9301

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  • Hemianopsia Patient Resources
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  • Hemianopsia Doctor Resources
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Calculators

Calculators

We use these things every day. Rather than hoard them in our own private Excel spreadsheets, we’re sharing them with the world! P.S. The world may not find them very useful. When processing lenses in the US, we make some assumptions about index of refraction that seem crazy to the rest of the world.

Aniseikonia Calculator

Diopters to Radius of Curvature Calculator

Transposition Calculator

Effective Power/Vertex Change

Sagitta Calculator

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© 2017 Chadwick Optical, Inc. All rights reserved.

The content on this site is what Chadwick Optical deemed relevant as of the date it was written. It has been significantly condensed to act as a marketing and sales tool, and should not be used as a scientific reference.

For scientific information on hemianopsia and the Peli Lens, please visit https://www.ncbi.nlm.nih.gov/pubmed?term=(peli+e[Author])