Brewster's Angle

\tan\theta_B = \frac{n_2}{n_1}

The angle of incidence at which reflected light is completely polarized.

Variables

θ_B

Brewster's angle

n₁

Refractive index of medium 1

Allowed values: 1 or more

unitless

n₂

Refractive index of medium 2

Allowed values: 1 or more

unitless

Your notes

0/5000

Check value

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n₁ = 1.5 (Refractive index of medium 1)
n₂ = 2.5 (Refractive index of medium 2)

Result: θ_B = 59.036243 °

Where this formula is listed

Optics formulas, under Polarization.
In the optics list it comes after Constructive Interference Condition and before Malus's Law.
Optics formula sheet, one of 34 formulas printed with symbol keys and SI units.
The full formula index, grouped by category and topic.

Common questions

What is the Brewster's Angle formula?

Brewster's Angle is written tan θ_B = n₂/n₁. The angle of incidence at which reflected light is completely polarized. It belongs to Optics, under Polarization.

What are the units in tan θ_B = n₂/n₁?

In SI units, θ_B is brewster's angle, measured in °; n₁ is refractive index of medium 1 (dimensionless); n₂ is refractive index of medium 2 (dimensionless).