The LCD screen itself does not emit light, and the backlight provides a light source for LCD screen imaging. However, the polarization direction of the emitted light is inconsistent and radiates. If such light passes through the twisting of LCD molecules, what we see on the screen may be a vast expanse of white or colorful green blocks. When the backlight passes through the incident polarizer of the liquid crystal box, only the light with the same vibration direction as the incident polarizer's polarization axis remains, that is, the surface is linearly polarized light. After passing through the liquid crystal box, the polarized light is then emitted from the polarizer.
The polarizer of an LCD screen serves as a filter for light. If there is no polarizing film on a LCD screen, there will be no display, because when the LCD screen is working, it mainly filters the light in the X or Y direction. At this time, only parallel light is available. Without polarizing film, it cannot be seen by the naked eye. Polarizing film is very thin, and if there are scratches, punctures, or abrasions, it cannot be used in production, so be careful when using it.
The function of polarizer is to play a developing role together with liquid crystal. In the production process, generally, the first step is to print two ordinary tempered glass pieces onto the circuit, apply a rubber frame around them, fold and press them in half, then inject liquid crystal in the middle of the two glass pieces, seal them above and below the glass, and attach polarizing films.
Both the upper and lower glass layers should be coated with polarizers, but pay attention to the direction. If the lower polarizer filters X-direction light, the upper layer can only filter Y-direction light. If the upper and lower layers are in the same direction, users cannot see anything. Although the LCD display is working normally, polarization cannot be seen with the naked eye. Nowadays, LCD screens usually only have an upper screen and no lower screen, which is a product of technological innovation.
Ruxin Gaoliang is committed to creating long-term value for our customers. We are a high-quality domestic LCD display manufacturer with 13 years of experience in research, development, production, and sales, specializing in various types such as high brightness screens, bar screens, and small-sized LCD screens. We provide one-on-one professional services for you.