Brewster’s Angle Apparatus OE-7035



The Brewster’s Angle Apparatus is designed to study the Brewster’s angle phenomenon and the polarization of reflected light. When light encounters a boundary between two media with different refractive indices, some of it is reflected and other part is transmitted. The fraction that is reflected is described by the Fresnel equations, and is dependent upon the incoming light’s polarization and angle of incidence.

When a light beam incident on a transparent material can be resolved into two light components i.e. parallel (P) and orthogonal (S) components. These components have different reflection coefficients and Brewster found that at a particular angle of incidence β (called Brewster angle), reflection co-efficient of parallel component goes zero. At this angle, direction of reflected and transmitted beam is orthogonal to each other.


Experiment Performed

  • To measure and plot the graph-reflectivity versus angle of incidence.
  • To find the Brewster’s angle (also known as the polarization angle) of glass plate and determination of refractive index.



  • Compact and integrated design
  • Good Quality polarizer
  • Sensitive photo detector
  • Precise measurement of rotation




Experimental set up Contain Quantity
Optical rail with stands length 1000 mm

Rotational stage

Kinematic laser mount

Polarizer with rotation mount

Glass slide

Diode laser <5mW (650nm or 532nm)

Diode laser power supply

Photo Detector with mount

Photo Detector Current meter