Lens and Mirror Equation Calculator

Solve thin-lens and spherical-mirror image distances with the real-is-positive Gaussian sign convention stated.

Element type

Positive converging or concave; negative diverging or convex.

Positive real image; negative virtual image.

Optional.

Optics result

Enter two distances

Real-is-positive Gaussian convention.

Image formation values
QuantityValueUnit
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1 / f = 1 / do + 1 / di; m = -di / do How?

How this is calculated

The solver uses the real-is-positive Gaussian convention. For mirrors it also reports the signed spherical radius as R = 2f.

Formula: 1 / f = 1 / do + 1 / di; m = -di / do

Sources

  1. OpenStax College Physics 2e, Image Formation by Lenses. OpenStax. Retrieved .
  2. OpenStax College Physics 2e, Image Formation by Mirrors. OpenStax. Retrieved .

Method last reviewed