LCD liquid crystal screen: TN screen, HTN screen, STN screen, VA screen difference?
Classification： Industry News
Release Time：2023-06-29 15:21
TN English name: TwistedNematic; Twisted orientation deflection of liquid crystal molecules 90 ° TN products belong to the category of LCM products, the main advantages are low power consumption and rich product display data TN, STN, FSTN LCD and LCD modules, COB, COG, TAB, CSTN, TFTLCD module products are suitable for mobile phones, industrial display modules, handheld electronic game consoles, calculators, perpetual calendars, electronic watches, electronic pets, electronic scales, car clocks, telephones, air conditioners, multimeters, electronic notepads, automobiles LCD remote control, radio, electronic instrument, walkie-talkie, car stereo, household appliances.
HTN (High Twisted Nematic, High Twisted Nematic) nematic liquid crystal molecules are sandwiched between two pieces of transparent glass. Between the two layers of glass, the orientation of liquid crystal molecules is deflected by 110~130 degrees. This type of LCD is characterized by high contrast, low power consumption, low driving voltage, and insufficient dynamic driving performance, but the viewing angle is wider than that of the TN type.
STN (SuperTwistedNematic) uses an electric field to change the arrangement of liquid crystal molecules that were originally twisted by more than 180 degrees to change the optical rotation state. The applied electric field changes the electric field by scanning line by line. In the process of repeatedly changing the voltage in the electric field, the recovery process of each point Slower, resulting in afterglow. Its advantage is that the power consumption is small, and it has the biggest advantage of saving electricity.
The display principle of color STN is to add a color filter to the traditional monochrome STN liquid crystal display, and divide each pixel in the monochrome display matrix into three sub-pixels, and display red, green and blue through the color filter respectively. base color, a color screen can be displayed. Unlike TFT, STN is a passive passive LCD, which can generally display up to 65536 colors.
Classification: Mainly divided into ordinary STN, FSTN, CSTN and DSTN.
Ordinary STN means that the liquid crystal rotates 180~270 degrees in the liquid crystal screen, and ordinary polarizers are pasted on the top and bottom of the liquid crystal screen. Because of dispersion, the background color of the liquid crystal screen will show a certain color, and the common ones are yellow-green or blue, which is commonly called Yellow-green mold or blue mold.
FSTN (Film+STN), in order to improve the background color problem of ordinary STN, add a layer of compensation film on the polarizer, which can eliminate dispersion and realize black and white display.
CSTN (ColorSTN), color STN, on the basis of FSTN technology, adds a layer of RGB color film to realize color display, and generally has a high number of driving channels.
DSTN (DoubleSTN), double-layer STN, one of which is used as the driving layer and the other as the compensation layer, belongs to the STN black and white technology, compared with FSTN, the contrast is higher, and it can automatically compensate for dispersion with temperature to achieve a wide temperature range high contrast.
The VA panel is a panel type that is widely used in high-end LCDs, and it belongs to a wide viewing angle panel. Compared with TN panels, 8bit panels can provide 16.7M colors and a large viewing angle is the high-end capital of this type of panel positioning, but the price is also more expensive than TN panels, and VA panels can be divided into MVA dominated by Fujitsu. panel and the PVA panel developed by Samsung, the latter is the inheritance and improvement of the former. The VA type panel has the highest frontal (front view) contrast ratio, but the uniformity of the screen is not good enough, and color drift often occurs. Sharp text is its killer feature, and black-and-white contrast is fairly high.