Polarization

Slotted Wave  A string can oscillate in a single plane. Transmission axisTransmission axis

Blocking Slot  The string is blocked if the slot is perpendicular to the motion.

Partial Blockage  If the string is at an arbitrary angle, part of the amplitude is blocked. Pass component parallel to slotPass component parallel to slot

Microwave Grid  EM waves can be polarized like a string. Grid slots must match wavelengthGrid slots must match wavelength

Polarized Light  Visible light has a wavelength that matches the size of large molecules.  Unpolarized light partially passes through  Polarized light is blocked based on the angle.

Liquid Crystal  Liquid crystal molecules are long and have electric dipole properties. Polarize light that passes throughPolarize light that passes through Respond to electric fieldRespond to electric field  A second polarizer changes light to dark.

LCD  An LCD display uses polarized light.  An external polarizer can detect the polarization. Tilt angle 90 degress  LCDs can use color as well.

Scattering  Molecules in the air scatter light.  Polarization occurs at an angle from the sunlight. next