How a Tft Display Works

Ⅰ. What is the TFT display

The TFT display is a thin-film liquid crystal display, but actually refers to a thin-film transistor, which can “actively” control each independent pixel on the screen and is the origin of the so-called active matrix TFT.

Ⅱ.  The working principle of TFT display

1. The display screen is composed of many pixels that can emit light of any color. As long as each pixel is controlled to display the corresponding color, the goal can be achieved.

2. Backlight technology is generally used in TFT and LCD. In order to accurately control the color and brightness of each pixel, it is necessary to install a shutter-like switch after each pixel. When the “blinds” are opened, light can pass through. When the “blinds” are closed, light cannot pass through.

3. There are generally three forms of liquid crystals: smectic liquid crystals similar to clay, filamentous liquid crystals similar to fine matchsticks, and liquid crystals similar to cholesterol. The TFT liquid crystal display screen uses filaments. When the external environment changes, its molecular structure will also change, and thus have different physical characteristics. It can achieve the purpose of making light pass through or blocking light—that is, the blinds just mentioned.

4. Everyone knows the three primary colors, so each pixel on the display screen needs three similar basic components described above to control the three colors of red, green, and blue respectively.

5. The TFT display screen has grooves on the upper and lower layers. The grooves on the upper layer are arranged vertically and the grooves on the lower layer are arranged horizontally. When no voltage is applied to the liquid crystal in its natural state, the light emitted from the schematic diagram of the working principle diagram of the luminous image twisted nematic TFT display screen will be twisted by 90 degrees after passing through the interlayer, so that it can be smoothly transmitted through the lower layer.

6. When a voltage is applied between the two layers, an electric field will be generated. At this time, the liquid crystals will be aligned vertically, so the light will not be twisted, and the result is that the light cannot pass through the lower layer.

Ⅲ TFT display pixel structure

Color filters are divided into three types: red, green, and blue according to their colors. They are arranged on the glass substrate to form a group corresponding to one pixel. Each monochromatic filter is called a sub-pixel. In other words, if a TFT display screen supports a maximum resolution of 1280×1024, then at least 1280×3×1024 sub-pixels and transistors are required. Pixels are decisive for the TFT display. The smaller each pixel is, the greater the maximum resolution that the display can achieve.