Brewster's Angle Calculator
Interactive Brewster's Angle Calculator for optics enthusiasts and professionals. Calculate the angle at which light with a specific polarization is perfectly transmitted through a surface with no reflection.
Interface
Provide the refractive index for the incident medium (n₁) and the transmitting medium (n₂) to compute Brewster's angle.
Angle (degrees) where reflected light is perfectly polarized and no reflection occurs for p-polarized light.
How to Use This Calculator
This tool helps physics students and optics professionals determine Brewster's angle at an interface. Enter the refractive index of the medium where light originates (n₁) and the index of the medium it enters (n₂). The calculator produces the angle in degrees where a particular polarization is completely transmitted with zero reflection.
Methodology
The calculation uses Snell's Law and Fresnel equations to derive Brewster's angle. It computes the arctangent of the ratio between the refractive indices and converts the result from radians to degrees, which matches how polarization-based optics experiments are analyzed.
Data Source and Methodology
All computations apply the conventional optics model for Brewster's angle. The calculator is audited for clarity and matches equations found in physics references on polarization at interfaces.
Glossary of Variables
- n₁: Refractive index of the incident medium (e.g., air = 1.0).
- n₂: Refractive index of the second medium (e.g., glass ≈ 1.5).
- θB (Brewster's Angle): The incidence angle at which p-polarized light encounters zero reflectance.
Example Calculation
Assume n₁ = 1.0 (air) and n₂ = 1.5 (glass). The calculator evaluates θB = arctan(1.5 / 1.0) and returns ≈ 56.31°. This is where reflected light is completely polarized.
Frequently Asked Questions
What is Brewster's Angle?
Brewster's Angle is the incidence angle at which reflected light is fully polarized with no reflection of p-polarized components.
Why is Brewster's Angle important?
It helps design anti-reflective coatings and optical setups where polarization control is critical.
Can Brewster's Angle exceed 90°?
No, Brewster's Angle always occurs between 0° and 90° at the interface boundary.
Does Brewster's Angle depend on wavelength?
Yes. Refractive indices vary with wavelength, so Brewster's Angle can shift slightly across colors.
How can I verify Brewster's Angle experimentally?
Adjust the incidence angle until the reflected beam is completely polarized; that is the Brewster angle.