Determine how much light will bend when passing from one medium to another using Snell's Law.
Optical Parameters
°
Common Indices
Calculation Results
Enter parameters to calculate
About this calculator
Quick Reference
n₁Index of incident medium
n₂Index of refractive medium
θ₁Angle of incidence
θ₂Angle of refraction
Overview
Refraction is the change in direction of a wave passing from one medium to another. The angle of refraction depends on the indices of refraction and the incident angle.
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Pro Tips
If n₂ > n₁, light bends towards the normal (θ₂ < θ₁).
If n₂ < n₁, light bends away from the normal (θ₂ > θ₁).
If the angle is too steep coming from a denser medium, total internal reflection occurs.
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Fun Facts
"Straws look bent in a glass of water because of refraction."
"The 'twinkling' of stars is caused by refraction as light passes through turbulent air."
"Lenses in cameras and glasses use refraction to focus light."
