Pn Junction

Plane polarized light consists of waves oscillating in a single plane perpendicular to the direction of propagation.

Obtaining polarized light by refraction:

When unpolarized light is incident at Brewster's angle on a transparent medium, the reflected light becomes plane polarized.

Uses of polaroid:

• Reducing glare in sunglasses and cameras.
• Enhancing contrast in liquid crystal displays (LCDs).

The depletion layer is the region around the - junction where mobile charge carriers are depleted, leaving behind immobile ions.
In a - junction, due to diffusion, electrons and holes recombine near the junction, leaving behind a region with immobile ions. This region forms the depletion layer, acting as a potential barrier for current flow.