Lensmaker's Equation Calculator
Use the Lensmaker's equation to determine the focal length and optical power (in diopters) of a lens from its refractive index and radii of curvature.
Inputs
Positive = center of curvature on right side
Negative = center of curvature on left side
Results
Focal Length
20.00 cm
Optical Power
5.00 D
Type
Converging (positive)
Lensmaker's Equation Results
| Parameter | Value |
|---|---|
| Focal Length f | 20.0000 cm |
| Optical Power P | 5.0000 D (diopters) |
| Refractive Index n | 1.5000 |
| R₁ | 20 cm |
| R₂ | -20 cm |
| Lens Type | Converging (positive) |
| (n-1) | 0.5000 |
| Formula | 1/f = (n−1)[1/R₁ − 1/R₂] |
Frequently Asked Questions
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