The tft-lcd liquid crystal display screen is a thin film transistor liquid crystal display screen

- Oct 08, 2019-

The tft-lcd liquid crystal display screen is a thin film transistor liquid crystal display screen, that is, the "true color" (tft) .tft liquid crystal display screen has a semiconductor switch for each pixel, and each pixel can be directly controlled by the tft liquid crystal display screen through the point pulse, so each node is relatively independent and can be continuously controlled, which not only improves the reaction speed of the display screen, but also accurately controls the display color level. So the color of tft liquid crystal is more real. In the fierce competition of many flat panel displays, why tft-lcd can stand out and become the mainstream display of the new generation is by no means accidental, and it is the necessity of the development of human science and technology and the development of thinking mode. Liquid crystal avoids the difficult luminous problem one after another. The light emitting display device is decomposed into two parts, that is, the light source and the control of the light source, by using the excellent characteristics of the liquid crystal as the light valve. As a light source, no matter from luminous efficiency, full color, or life, has achieved brilliant results, and is still deepening. Since the invention of LCD, the backlight source has been constantly improving, from monochromatic to color, from thick to thin, from side fluorescent lamp to flat fluorescent lamp. The latest achievements in luminous light source will provide a new backlight source for lcd. With the progress of light source technology, there will be updated better light source and applied by lcd. The rest is the control of the light source, the technology and process of semiconductor large scale integrated circuit (VLSI), the production process of thin film transistor (tft) is successfully developed, the matrix addressing control of liquid crystal light valve is realized, and the cooperation between light valve and controller of liquid crystal display is solved, so that the advantages of liquid crystal display can be realized. 

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The tft of how tft works is the abbreviation of "thin film transistor", which generally refers to the thin film liquid crystal display, but in fact refers to the thin film transistor (matrix), which can "actively" control the independent pixels on the screen, which is the origin of the so-called active matrix tft (active matrix tft). So how on earth did the image come into being? The basic principle is simple: the display screen consists of many pixels that can emit light of any color, as long as each pixel is controlled to display the corresponding color. Backlight technology is generally used in tft 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 shutter is turned on, the light can pass through, while the shutter can not pass through when the shutter is closed. Of course, it's not technically as simple as it just said. LCD (liquid crystal display) makes use of the characteristics of liquid crystals (liquid when heated and crystallization as solid when cooled). There are three forms of liquid crystals: clay-like layered (smectic) liquid crystals, like fine matches, filamentous (nematic) liquid crystals, cholesterol-like (cholestic) liquid crystal displays, which use filamentous. When the external environment changes, its molecular structure also changes, so it has different physical properties-it can achieve the purpose of allowing light to pass through or block light-that is, the blinds, for example. You know the three primary colors, so each pixel on the display screen needs the three similar basic components described above to control the red, green and blue colors respectively. The most commonly used is the twist nematic tft liquid crystal display (twisted nematic tft lcd), figure below is the explanation of the working principle of this kind of tft display. There are great differences in existing technologies, which we will cover in detail in the second part of this article. There are grooves in the upper and lower layers, in which the grooves in the upper layer are arranged longitudinally and the lower layers are arranged horizontally. When the liquid crystal without voltage is in a natural state, the light emitted from the working principle of the tft display from the light emitting figure 2A to the column display through the interlayer will be distorted by 90 degrees, so that it can pass through the lower layer smoothly. When a voltage is added between the two layers, an electric field is generated, and the liquid crystals are arranged vertically, so the light does not twist-as a result, the light cannot pass through the lower layer. (2) tft pixel structure: according to the color, the color filter is divided into three kinds: red, green and blue, and then arranged on the glass substrate 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. 

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