Difference between revisions of Diopters

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Diopters is a measure of the power of a [[lens]] (or mirror).  It is equal to 1/[[focal length]] in meters.  In EM we refer to the [[cm measurement]] to calculate diopters needed to correct [[refraction]] of the eye.
Diopters is a measure of the power of a [[lens]] (or mirror).  It is equal to 1/[[focal length]] in meters.  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 1/0.5=2 diopters.


Diopters are cancels each other. If you're wearing -2 diopter contacts 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]]
A lens with a negative diopter sign compensates for [[nearsightedness]] while a lens with a positive diopter sign compensates for [[farsightedness]]


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-10.00+ - Very high myopia. Field of view significantly reduced.
-10.00+ - Very high myopia. Field of view significantly reduced.
Diopters are calculated by the formula D=1/f where f is the distance in meter to blur.
If you can see 50cm clearly your diopters will be 1/0.5=2 diopters.