Brewster's Angle Calculator

Calculate the angle of perfect polarization using Brewster's law: θB = arctan(n₂/n₁)

Calculate Brewster's Angle

Refractive index of initial medium (typically air = 1.000)

Refractive index of reflecting medium

Brewster's Angle Results

Brewster's Angle

0.00°
Angle of perfect polarization

Critical Angle

N/A
No total internal reflection

Polarization Ratio

N/A
n₂/n₁ ratio

Brewster's Law: θB = arctan(n₂/n₁)

Perfect Polarization: Reflected light is 100% linearly polarized

Condition: Angle of reflection + angle of refraction = 90°

Physics Analysis

Common Materials

Interface Examples

Key Concepts

θ

Brewster's Angle

Angle of incidence for perfect polarization

P

Polarization

Reflected light becomes linearly polarized

n

Refractive Index

Material property affecting light speed

Applications

🕶️

Polarized sunglasses

📸

Photography filters

🔬

Optical instruments

💻

LCD displays

🌊

Glare reduction from water

🚗

Anti-glare car windows

Understanding Brewster's Angle

What is Brewster's Angle?

Brewster's angle is the angle of incidence at which light with a particular polarization is perfectly transmitted through a transparent dielectric surface, with no reflection. When unpolarized light hits a surface at this angle, the reflected light becomes completely linearly polarized.

Physical Principle

  • Reflection and refraction angles sum to 90°
  • p-polarized light experiences zero reflection
  • s-polarized light is partially reflected
  • Result: reflected light is linearly polarized

Brewster's Law

θB = arctan(n₂/n₁)

  • θB: Brewster's angle
  • n₁: Refractive index of initial medium
  • n₂: Refractive index of second medium

Note: Named after Scottish physicist Sir David Brewster (1781-1868) who discovered this phenomenon in 1815.

Polarization Types

s-Polarized

Electric field perpendicular to plane of incidence, partially reflected at Brewster's angle

p-Polarized

Electric field parallel to plane of incidence, zero reflection at Brewster's angle

Unpolarized

Equal mix of s and p components, becomes linearly polarized after reflection