Describe, with the aid of a diagram, how a wave can be plane polarized.
Light is a transverse wave. In an unpolarized light wave, the vibrations occur randomly in all directions perpendicular to the direction of travel.
To produce plane-polarized light, pass the unpolarized light through a Polaroid sheet (polarizer). The Polaroid transmits only the component of vibration parallel to its transmission axis and absorbs the components in other directions. The emergent wave therefore vibrates in one direction only and is said to be plane polarized.
Plane polarization of light by transmission through a Polaroid sheet.
In the diagram, the transmitted electric-field vibrations are all vertical, parallel to the transmission axis of the polarizer. Thus, they are restricted to one plane containing the direction of propagation.
Light is a transverse wave. In an unpolarized light wave, the vibrations occur randomly in all directions perpendicular to the direction of travel.
To produce plane-polarized light, pass the unpolarized light through a Polaroid sheet (polarizer). The Polaroid transmits only the component of vibration parallel to its transmission axis and absorbs the components in other directions. The emergent wave therefore vibrates in one direction only and is said to be plane polarized.
Plane polarization of light by transmission through a Polaroid sheet.
In the diagram, the transmitted electric-field vibrations are all vertical, parallel to the transmission axis of the polarizer. Thus, they are restricted to one plane containing the direction of propagation.