Difference between revisions of Diopters
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* http://billauer.co.il/simulator.html | * http://billauer.co.il/simulator.html | ||
=== Decentration === | |||
The Induced prism can be calculated using Prentice reign. Similar to Vertex Distance, shift is less of an issue for lower power lenses. | |||
The amount of prism power P induced by the decentration c of a lens of power f is <math>P=cf</math> 1 prism diopter displaces 1 cm for an object 1 m away. If c is in cm and f in diopters, then P is in prismatic diopters. A prism with vertex angle a and refractive index n gives an angle of light deflection d, which is equal to P diopters of the prism: <math>d=(n - 1)a</math> <math >P=100\tan{d}=100\tan((n - 1)a)</math> | The amount of prism power P induced by the decentration c of a lens of power f is <math>P=cf</math> 1 prism diopter displaces 1 cm for an object 1 m away. If c is in cm and f in diopters, then P is in prismatic diopters. A prism with vertex angle a and refractive index n gives an angle of light deflection d, which is equal to P diopters of the prism: <math>d=(n - 1)a</math> <math >P=100\tan{d}=100\tan((n - 1)a)</math> | ||
See [[Vertex distance#Calculation|Vertex distance -> Calculation]] | |||
== References == | |||
{{ reflist }} | {{ reflist }} | ||
[[ Category: Article ]] | [[ Category: Article ]] | ||