Working Principle Of LCD Screen

The liquid crystal material is filled between the two parallel plates, and then the arrangement of the molecules inside the liquid crystal material is changed by voltage, so as to achieve the purpose of shading and transmitting light to display images of different shades, and as long as the two A three-color filter layer is added between the flat plates, and a color image can be displayed.

The structure of the LCD liquid crystal screen is to place liquid crystal material in two parallel pieces of glass. There are many vertical and horizontal thin wires in the middle of the two pieces of glass. The rod-shaped crystal molecules are controlled by whether they are powered on or not, thereby changing the direction, and refract its light to produce a picture. It is much better than CRT, but its price is more expensive.

Liquid crystal is an organic compound composed of long rod-shaped molecules. In their natural state, the long axes of these rod-like molecules are roughly parallel.

One of the characteristics of LCD liquid crystal screen: the liquid crystal must be poured between two planes with thin grooves to work normally. The grooves on these two planes are perpendicular to each other (intersection at 90 degrees), then that is, if the molecules on one plane are aligned north-south, the molecules on the other plane are aligned east-west, and the molecules in the two planes are aligned The molecules in between are forced into a 90-degree twist. Since light travels in the direction of the alignment of the molecules, the light is also twisted 90 degrees as it passes through the liquid crystal. But when a voltage is applied to the liquid crystal, the molecules are re-aligned vertically so that the light can go straight out without any twisting.

The second feature of LCD: it relies more on polarized filters and the light itself. Natural light is randomly distributed in all directions. Polarized filters are actually a series of thinner and thinner parallel lines. These lines form a net that blocks all light rays that are not parallel to these lines. The lines of the polarizing filter are also exactly perpendicular to Di, so they can completely block the light that has been polarized. Light can only penetrate if the lines of the two filters are perfectly parallel, or if the light itself has been twisted to match the second polarizing filter. The LCD is made up of such two mutually perpendicular polarized filters, so under normal circumstances all the light that tries to penetrate should be blocked. However, since the two filters are filled with twisted liquid crystals, when the light passes through the Di filter, it will be twisted 90 degrees by the liquid crystal molecules, and Zui will then pass through the second filter. . On the other hand, if a voltage is applied to the liquid crystal, the molecules will be rearranged and completely parallel, so that the light will not be twisted any more, so it is just blocked by the second filter. In short, power on can block light, and no power can let light out. Of course, the arrangement of the liquid crystals in the LCD screen can also be changed, so that the light is emitted when it is powered on, and will be blocked when it is not powered on.