The LCD display is a flat and ultra-thin display device. It consists of a certain number of color or black and white pixels and is placed in front of a light source or reflective surface. LCD monitors have very low power consumption, so they are popular with engineers and are suitable for battery-powered electronic devices. Its main principle is that the current stimulates the liquid crystal molecules to generate dots, lines, and surfaces in cooperation with the back light tube to form a picture.

Liquid crystal is an organic compound that exhibits both the fluidity of liquids and the optical anisotropy of crystals under normal temperature conditions, so it is called "liquid crystal." In external conditions such as electric fields, magnetic fields, temperature, and stress, Under the influence, its molecules are easily rearranged, which causes various optical properties of liquid crystals to change. The anisotropy of liquid crystals and their molecular arrangement are easily controlled by external electric and magnetic fields. It is the physical basis of using this liquid crystal That is, the "electric-optical effect" of liquid crystal, which realizes the modulation of light by electrical signals, thereby making a liquid crystal display device. Under the action of different current electric fields, the liquid crystal molecules will be regularly rotated 90 degrees to arrange, resulting in a difference in light transmission. There is a difference between light and dark under power ON / OFF, and each pixel is controlled according to this principle to form the desired image.

The physical characteristics of liquid crystals are: when the power is turned on, the arrangement becomes orderly, allowing light to pass easily; when the power is not turned on, the arrangement is disordered, preventing light from passing. Let the liquid crystal block like a gate or let light pass through. Technically speaking, the LCD panel contains two pieces of very delicate sodium-free glass material, called Substrates, with a layer of liquid crystal sandwiched between them. When the light beam passes through this layer of liquid crystal, the liquid crystal itself will stand in a row or twist in an irregular shape, thus blocking or allowing the light beam to pass through smoothly. Most liquid crystals are organic complexes composed of long rod-shaped molecules. In the natural state, the long axes of these rod-shaped molecules are approximately parallel. Pour the liquid crystal into a well-processed slotted plane, and the liquid crystal molecules will be aligned along the grooves, so if those grooves are very parallel, the molecules are also completely parallel.