Brewster’s Angle in Physics
Brewster angle is defined as the angle of incidence at which light with parallel polarization state is perfectly transmitted through the boundary with no reflection and light with perpendicular polarization state is reflected. The reflected light is completely polarized and has electric field oscillation confined to single plane only.
Mathematically Brewster Angle is given as
θB = tan-1(n2/n1)
where n1 and n2 are the refractive indices of the two media involved
Derivation of Brewster’s Angle
Brewster angle can be calculated as,
μ = n2/n1
tan θB = n2/n1
θB = tan-1(n2/n1)
θB = tan-1(μ)
Brewster’s Angle and Critical Angle
Critical angle is the angle of incidence at which light is refracted at an angle of 90 degrees with respect to the normal, when it is incident on the boundary between two different media.
Since, μ = 1/Sin θc
Brewster Angle is given as θB = tan-1(n2/n1)
Hence, θB = tan-1(n2/n1) = tan-1(cosec θc )
Brewster’s Law – Definition, Formula, Derivation, Example, Uses
Brewster’s Law states that when unpolarized light strikes a surface at a specific angle (Brewster angle), the reflected light becomes polarized perpendicular to the plane of incidence. According to Brewster Law of polarization, the refractive index of a medium is equal to the tangent of the polarizing angle. This law finds applications in making polarizing filters for reducing glare in sunglasses and improving image quality in cameras, LCD screens, and optical devices by selectively transmitting polarized light.
In this article we will learn in detail about Brewster Law of Polarization, its formula, derivation, relationship with snell’s law and its application. We will also learn about Brewster angle and its relationship with critical angle in this article.
Table of Content
- What is Brewster’s Law
- Brewster’s Law Formula
- Brewster’s Angle in Physics
- Brewster’s Law Experiment
- Applications of Brewster’s Law
- Solved Examples on Brewster Law