Difference between revisions of Diopters
Added unit symbols, added some math formatting, cleared up some confusing range formatting. |
Dlskidmore (talk | contribs) m formatting |
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<math>D = \frac{1}{f}</math> | <math>D = \frac{1}{f}</math> | ||
In [[EM]] we refer to the [[cm measurement]] to calculate diopters needed to correct [[refraction]] of the eye. If you can see 50cm clearly your diopters will be <math>\frac{1}{0.50}=2dpt</math>. | * In [[EM]] we refer to the [[cm measurement]] to calculate diopters needed to correct [[refraction]] of the eye. If you can see 50cm clearly your diopters will be <math>\frac{1}{0.50}=2dpt</math>. | ||
Lenses in series add their powers : if you're wearing -2 diopter contacts ([[vertex distance|adjusted for glasses strength]]) and put +1 diopter reading glasses over the contacts you're in effect wearing -1 diopters. | |||
A lens with a negative diopter sign compensates for [[nearsightedness]] while a lens with a positive diopter sign compensates for [[farsightedness]]. | * Lenses in series add their powers : if you're wearing -2 diopter contacts ([[vertex distance|adjusted for glasses strength]]) and put +1 diopter reading glasses over the contacts you're in effect wearing -1 diopters. | ||
* A lens with a negative diopter sign compensates for [[nearsightedness]] while a lens with a positive diopter sign compensates for [[farsightedness]]. | |||
{| class="wikitable" | {| class="wikitable" | ||