The LCD panel is mainly composed of the following eight parts:
1, backlight (or backlight module):
Since the liquid crystal molecules themselves cannot emit light, if a picture is desired, the liquid crystal screen requires a special light source to provide light, and then the liquid crystal molecules are deflected to produce different colors. The backlight plays a role in providing light energy. Previously, the LCD screen used a cold cathode ray tube called CCFL. The principle of illumination was almost the same as that of fluorescent lamps, and the new LCD screens used LED backlights with more energy-saving and longevity. After the lamp (or LED) emits light, the light is distributed through the light guide plate, and the direction of all the light is concentrated toward the liquid crystal molecules through the reflector on the back surface. Finally, the light is evenly emitted through the prism sheet and the diffuser plate to avoid the situation where the central brightness is too high and the surrounding brightness is too low.
2. Two polarizers on the upper and lower layers:
The role of the polarizer is to allow light to pass through in one direction.
3. Two glass substrates on the upper and lower layers:
The glass substrate is not only as simple as two pieces of glass, but has a grooved structure on the inside and an alignment film attached to allow the liquid crystal molecules to be aligned neatly along the grooves. A TFT thin film transistor and a color filter are attached to both sides of the upper and lower glass layers.
4. ITO transparent conductive layer:
Its function is to provide a conductive path, which is divided into a pixel electrode (P level) and a common electrode (M level).
5, thin film transistor (which we often call TFT):
The TFT-LCD, which is often referred to, actually refers to this thin film transistor, which functions like a switch. The TFT can control the signal voltage on the IC control circuit and transport it to the liquid crystal molecules to determine the angle at which the liquid crystal molecules are deflected. Size, so it is a very important part.
6, liquid crystal molecular layer:
It is the most important element for changing the state of light polarization, and its arrangement and polarization state are determined by electric power and elastic force.
7, color filter:
The light deflected by the liquid crystal molecules can only display different gray scales, but can not provide three primary colors of red, green and blue (RGB), while the color filters are composed of three kinds of RGB filters, and the colors are adjusted by mixing the three colors. brightness. Each pixel in the liquid crystal panel is composed of three points of red, green and blue, and each color point has a different gray scale change.
8, frame glue;
It is to make the upper and lower glass substrates in the liquid crystal panel firmly adhere together, and to "insulate" the entire internal system from the external, preventing dust from entering the color effect.
Related tags: LCD screen manufacturer, LCD screen, LCD display module