What this calculator does
Brewster's Angle works out angle of incidence where reflected light becomes fully polarized, from two refractive indices. Enter your own figures above and the answer updates as you type: nothing is fixed in the code, so the result reflects exactly the numbers you supply.
The formula this calculator evaluates is printed under the tool and explained below, so you can check the working by hand or reuse it in a spreadsheet.
The formula
The inputs explained
| Field | What to enter |
|---|---|
| Refractive index of incident medium (air ≈ 1.00) | A number. Starts at 1. |
| Refractive index of second medium (glass ≈ 1.50) | A number. Starts at 1.5. |
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
How the answer changes with refractive index of incident medium (air ≈ 1.00)
Every other input is held at the calculator’s starting values while refractive index of incident medium (air ≈ 1.00) varies. Select any row to load that scenario into the calculator.