To achieve optimum polarization by reflection, the light must strike a surface at a specific angle known as the Brewster angle. This angle is crucial because it is the point at which the reflected light is completely polarized perpendicular to the plane of incidence.
The Brewster angle varies depending on the materials involved. It can be calculated using the formula:
θ_B = arctan(n2/n1)
In this formula:
- θ_B: Brewster angle
- n1: Refractive index of the first medium (usually air)
- n2: Refractive index of the second medium (the surface being reflected from)
Since different materials have different refractive indices, the Brewster angle will differ from one material to another. For example, the Brewster angle for light transitioning from air to water will be different than that for light moving from air to glass.
In summary, the condition for optimum polarization by reflection is indeed linked to the Brewster angle, and no, this angle is not the same for every material because it is dependent on each material’s refractive index.