PHYSICAL QUANTITY

Lens power: formulas and units of measurement

Lens power: symbol D, unit diopter. Formulas and explanations for Optics.

D

\text{dpfr}

diopter

KEY CONNECTIONS

Formulas

D = \frac{1}{F}

D = 1 / F

D = \frac{1}{d} + \frac{1}{f}

D = 1 / d + 1 / f

D = D_{1} + D_{2}

D = D₁ + D₂

NOTATION

$D$: Optical power is the ability of a lens to collect or scatter light.
$F$: Focal length is the distance from the optical center of the lens to its main focus.
$d$: Object distance - the distance from the lens to the object in question.
$f$: Image distance is the distance from the lens to the resulting image.
$D_1$: The optical power of the first lens is the refractive power of the first lens of the system.
$D_2$: The optical power of the second lens is the refractive power of the second lens of the system.

THEORY

PRACTICE