How does TFT Display work?

- Nov 11, 2019-

TFT is the short "thin film transistor" of the "active", commonly referred to as a thin-film liquid crystal display, and in practice refers to a thin-film transistor (matrix)--which can be used to control the iTFT Display ndividual pixels on the screen, that is, the so-called active matrix tft. So what's the picture? The basic principle is simple: the display screen is composed of a plurality of pixels which can emit light of any color, so that the purpose is achieved by controlling each pixel to display the corresponding color. In a tft lcd, a backlight technique is generally employed in order to be able to accurately control the color and brightness of each pixel, it is necessary to install a blind-like switch after each pixel, and when the "Louver" is turned on, the light can pass through, and the light cannot be transmitted after the "Louver" is closed. Of course, technically, it's not as simple as it was. lcd (liquid crystal display) is the characteristic of liquid crystal (when heated to a liquid state, and when it is cooled, the crystal is solid), and the liquid crystal has three forms: 


*Layered (smectic) liquid crystals similar to clay

*like fine match rods filamentous (nematic) liquid crystals 

*similar cholesterol-like (cholestic) liquid crystals 

4.3INCH TFT Display

The use of a liquid crystal display is a filament, and when the external environment changes its molecular structure will also change, so that it has different physical properties--the purpose of allowing light to pass or block the light--that is, just the shutter of the side.


The three primary colors are known so that each pixel on the display screen needs three similar basic components as described above to control the three colors of red, green and blue, respectively. 

4.3INCH TFT Display

The most common use today is a twisted nematic liquid crystal display (tft lcd), which is the working principle of such a tft display as explained. The existing technology is very different and we will be described in detail in the second part of this article.


On the upper and lower layers there are grooves in which the upper layers of the grooves are arranged in the longitudinal direction and the lower layers are arranged laterally. When the voltage-free liquid crystal is in a natural state, a 90-degree twist can occur after the light that diverges from the schematic diagram of the twisted nematic tft display of the light-emitting figure 2a through the interlayer, so that it can be smoothly transmitted in the lower layer. 


When a voltage is applied between the two layers, an electric field is generated, at which time the liquid crystal is vertically arranged so that the light does not twist--the result is that the light cannot pass through the lower layer. 


Tft pixel architecture: color filters are divided into red, green and blue according to color. They are arranged on glass substrate in turn to form a group of (dot pitch) corresponding to a pixel. Each monochromatic filter is called sub-pixel. In other words, if a tft display supports a maximum resolution of 1280 × 1024, at least 1280 × 3 × 1024 subpixels and transistors are required. 


For a 15-inch tft display (1024 × 768), then a pixel is about 0.0188 inches (equivalent to 0.30mm), and for an 18.1-inch tft display (1280 × 1024), it is 0.011 inches (equivalent to 0.28mm). As we all know, pixels are decisive for displays, and the smaller each pixel, the greater the maximum resolution that the display can achieve. However, due to the limitations of the physical characteristics of transistors, the size of each pixel in tft is basically 0.0117 inches (0.297mm) at this stage, so for a 15-inch display, the maximum resolution is only 1280 × 104.