Snell’s Law Calculator

Snell’s Law Calculator

Ref. Index1

Ref. Index2




Snell’s Law(Law of Refraction): gives us a way of predicting the amount of bend. It involves the angles that the incident ray and the refracted ray make with the normal to the surface at the point of refraction

Refraction depends on the media through which the light rays are travelling which is represented by the refractive index, numbers which are constant for given media


Ref. Index1 * Sin(θincidence) = Ref. Index2 * Sin(θrefraction)

Ref. Index1 : Refractive Index of 1st medium

Ref. Index2 : Refractive Index of 2nd medium

θincidence : Angle of Incidence of 1st medium i.e. angle between incident ray and normal.

θrefraction : Angle of Refraction of 2nd medium i.e. angle between refracted ray and normal.

For Example:

Suppose,Ray of light of wavelength 600 nm travels from water into air, so that it makes a 15° angle with the normal of the boundary. Suppose we wish to find the angle of refraction (x), where refractive index of water is 1.33 and refractive index of air is 1.00029. Then, Snell’s Law gives

1.33 * sin 15° = 1.00029 * sin x

x = 20.12°

Units: Refractive Index of various mediums