Question

3. What is the name of the angle at which windows are typically oriented in lasers? Find the angle shown in the figure below, given that the laser tube has a refractive index of n 1.5 Which type of polarization oscillates and is emitted by the laser?

Answer 1

The angle at which windows are typically oriented in lasers is called Brewster's angle.

It is an angle of incidence at which p- polarized light is perfectly transmitted through a transparent dielectric surface.

at this angle, the unpolarized (monochromatic or light with various wavelengths ) is incident, light is s- polarized and reflected.

glass refraction index= 1.5 , and refraction index of air = 1.

therefore , Brewster’s angle = tan^-1(1.5/1) = 56.3^o

polarization is of two types P- polarized(electric field parallel to the plane of the incident) and s- polarization(electric field perpendicular to plane of the incident)

when the light is incident at this angle, then it is reflected and produce s-polarized.

when p- polarized light is incident, then it is perfectly transmitted without reflection