Determine the focal length of a thin lens from its radii of curvature and the refractive index of the lens material. Supports biconvex, biconcave, and plano configurations.
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Refractive index of the lens material.
First surface radius. Positive if center is behind the surface.
Second surface radius. Negative if center is in front of the surface.
How this calculator works
The lens maker's equation relates focal length f to the refractive index n of the lens material and the radii of curvature R1 and R2 of the lens surfaces.
Common questions about this calculator
These calculators are for educational and informational purposes only. While we strive for accuracy, results should be verified for critical applications. Always consult authoritative sources for engineering or scientific work.
