According to different backlight sources, LCD can be divided into CCFL and LED.
Many users think that liquid crystal displays can be divided into LED and LCD, which to some extent is misled by advertisements.
The LED display screen mentioned in the market is not an LED display screen in the real sense. To be precise, it is an LED backlight liquid crystal display. The liquid crystal panel is still a traditional LCD display screen. In a sense, this is somewhat fraudulent!
South Korea's Samsung company was once convicted by the British Advertising Association of violating the country's advertising law because its 'LEDTV' LCD TV was suspected of misleading consumers.
For liquid crystal displays, the most important key is their liquid crystal panel and backlight type, while the liquid crystal panel of displays on the market generally adopts TFT panel, which is the same, the only difference between LED and LCD is that their backlight types are different: LED backlight and CCFL backlight (That is, fluorescent lamps), Respectively, diode and cold cathode lamp tube.
LCD is the acronym of Liquid Crystal Display, which means 'Liquid Crystal Display', that is, Liquid Crystal Display. And LED refers to a liquid crystal display (LCD)One of them, that is, LED (Light emitting diode)Liquid Crystal Display for backlight source (LCD).
Visible, LCD is, including LED.
What corresponds to the LED is actually CCFL. Refers to CCFL (Cold Cathode Fluorescent tube)Liquid Crystal Display as backlight source (LCD).
The advantage of CCFL is good color performance, but the disadvantage is high power consumption. Refers to the LED (Light emitting diode)Liquid Crystal Display as backlight source (LCD), Usually refers to WLED (White LED).
The advantages of LED are small volume and low power consumption, so using LED as backlight source can achieve higher brightness while taking into account both lightness and thinness.
The main disadvantage is that the color performance is worse than CCFL, so most professional drawing LCD still uses traditional CCFL as backlight light source. TN (Twisted Nematic): Twisted directional liquid crystal with positive TN-
LCD to speak, when no voltage is applied to the electrode, the LCD is in the 'OFF' state, and the light energy penetrates the LCD in the white state;
When the LCD with voltage applied to the electrode is in the 'ON' State, the long axis direction of the liquid crystal molecules is arranged along the direction of the electric field, and the light cannot pass through the LCD and is in a black state.
Selectively applying a voltage to the electrode can show different patterns.
Torsion angle 0 ~ 90 degrees, View Angle 0 ~ About 30 degrees, small viewing angle, poor contrast, used to be used in electronic computers, watches, and so on. STN (Super-Twisted Nematic)
: Super-twisted directional liquid crystal, for STN-
LCD, the distortion angle of the liquid crystal is larger, so the contrast is better and the viewing angle is wider. STN-
LCD is based on the principle of birefringence display, its base color is generally green, blue font, become Green mode.
When the purple polarizer used, the base color turns gray and becomes gray. FSTN (Formulated STN)
: The thin film compensates the super-twist directional liquid crystal. When the STN substrate uses the polarizer of the compensation film, the primary color will become close to White. This stthe STN to become a black and white die, which is FSTN.