Enter the refractive indices of two different mediums and the angle of refraction into the calculator to determine the angle of incidence.

Angle of Incidence Formula

The following formula is used to calculate the angle of incidence.

θ1 = sin^{-1} ( n2 * sin (θ2) / n1 ) 
  • Where θ1 is the angle of incidence
  • θ2 is the refraction angle
  • n2 is the refractive index of medium 2
  • n1 is the refractive index of medium 1

To calculate the angle of incidence, multiply the refractive index of the 2nd medium by the sine of the refraction angle, then divide by the refractive index of the 1st medium. Finally, take this result and take the inverse sine of it to get the angle of incidence.

Angle of Incidence Definition

An angle of incidence is defined as the angle between the ray incident on a surface and the line perpendicular to the surface.

Angle of Incidence Example

How to calculate the angle of incidence?

  1. First, determine the refractive indices.

    Calculate the refractive index of both mediums.

  2. Next, determine the angle of refraction.

    Calculate or measure the refraction angle.

  3. Finally, calculate the angle of incidence.

    Calculate the angle of incidence using the equation above.

FAQ

What is a refraction?

A refraction is defined as the change in the relative angle of reflected light based on the speed of light through two different mediums.