caclculate angle of incidence and angle of reflection

Free calculate the angle of incidence from the surface normal and incident ray direction for reflection and refraction calculations.

Input Parameters

Angle from horizontal (0° = horizontal)

Angle of incoming ray from horizontal

Results

Enter angles to calculate angle of incidence

Angle of Incidence

Definition

The angle of incidence is the angle between the incident ray and the surface normal.

θᵢ = |θᵣₐᵧ - θₙₒᵣₘₐₗ|

Key Points

  • • Measured from normal (90° from surface)
  • • Always between 0° and 90°
  • • Equal to angle of reflection
  • • Used in Snell's law for refraction

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