A liquid crystal display (liquid-crystal display) is a flat-panel display device consisting of a certain number of color or black-and-white pixels placed in front of the light source or the reverse side. LCD monitors are low power consumption and are therefore favored by engineers for use in battery-operated electronic devices. Its main principle is to stimulate the liquid crystal molecules to generate dots, lines and faces to match the back lamp.
Each pixel of the liquid crystal display is composed of a liquid crystal molecular layer suspended between two transparent electrodes (indium tin oxide) and two polarizing filters having polarization directions perpendicular to each other on the outer sides.
If there is no liquid crystal between the electrodes, the light passes through one of the polarizing filters and its polarization direction will be completely perpendicular to the second polarizing plate, and thus is completely blocked. However, if the direction of polarization of the light passing through a polarizing filter is rotated by the liquid crystal, it can pass through another polarizing filter. The rotation of the liquid crystal to the polarization direction of the light can be controlled by an electrostatic field, thereby achieving control of the light.