Simply put, the basic principle of screen display is to fill liquid crystal material between two parallel plates. The arrangement of molecules in liquid crystal materials is changed by voltage to display different shades and uniform images in order to achieve the purpose of shading and translucency. Moreover, as long as a three-color filter layer is added between two plates, the color image can be displayed.
Only by understanding its structure and principle and its technical and technological characteristics, can we have a definite aim in selecting and purchasing, and be more scientific and reasonable in application and maintenance. Liquid crystal is an organic compound composed of long rod-like molecules. In the natural state, the long axes of these rod-like molecules are roughly parallel. The first characteristic of LCD is that liquid crystal must be injected between two planes with thin grooves in order to work properly. The slots on the two planes are perpendicular to each other (90 degrees intersect), that is to say, if the molecules on one plane are arranged in the North-South direction, the molecules on the other plane are arranged in the East-West direction, and the molecules between the two planes are forced into a 90 degree twist state. As light travels along the molecular alignment, it is also reversed by 90 degrees as it passes through the liquid crystal. But when a voltage is applied to the liquid crystal, the molecules are rearranged vertically so that the light can be directed out without any twist.
The second feature of LCD is that it relies on polarization filters and light itself, and natural light is scattered randomly in all directions. Polarization filters are actually a series of thinner and thinner parallel lines. These lines form a network to block all light rays that are not parallel to these lines. The line of the polarization filter is just perpendicular to the first line, so that the polarized light can be completely blocked. Only when the lines of the two filters are completely parallel or the light itself has been twisted to match the second polarized filter can the light penetrate. On the one hand, LCD is made up of two polarized filters which are perpendicular to each other, so under normal circumstances, all the light that is trying to penetrate should be blocked.
However, due to the distorted liquid crystal between the two filters, the liquid crystal molecule will twist 90 degrees after the light passes through the first filter, and finally pass through the second filter. On the other hand, if a voltage is applied to the liquid crystal, the molecules are rearranged and completely parallel, so that the light is no longer twisted, so it is blocked by the second filter. In short, the light will be blocked by adding electricity, and light will be emitted without adding electricity. Of course, it can also change the arrangement of liquid crystals in LCD, so that light can be emitted when electrified, but not blocked when electrified. But because the LCD screen is almost always on, only the "power-up will block the light" scheme can achieve the most power-saving purposes.
