Difference between revisions of Diopters
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<math>P = \frac{1}{f} = - \frac{1}{d}</math> | <math>P = \frac{1}{f} = - \frac{1}{d}</math> | ||
* We use the [[ cm measurement ]] to calculate the diopters needed to correct [[ refraction]] of the eye. If you can see clearly at 50cm, your diopters will be <math> - \frac{1}{0.50}= - 2 dpt</math> OR <math> - \frac{100}{50}= - 2 dpt</math>. | * We use the [[ cm measurement ]] to calculate the diopters needed to correct [[ refraction]] of the eye. If you can see clearly at 50cm, your diopters will be <math> - \frac{1}{0.50}= - 2 \ \text{dpt}</math> OR <math> - \frac{100}{50}= - 2\ \text{dpt}</math>. | ||
* Serial lenses add their powers: if you wear - 2 diopter contact lenses ( [[ vertex distance | adjusted for glasses strength ]] ) and put on reading glasses +1 diopter on the lenses you actually wear - 1 diopter. | * Serial lenses add their powers: if you wear - 2 diopter contact lenses ( [[ vertex distance | adjusted for glasses strength ]] ) and put on reading glasses +1 diopter on the lenses you actually wear - 1 diopter. | ||