TFT (Thin Film Transistor)

TFT (Thin Film Transistor) is an active matrix type LCD liquid crystal displays (LCD) AM - the kind. LCD flat panel display, special tft-lcd, is the only one in the brightness, contrast, power consumption, long life, bulk and weight etc comprehensive performance in an all-round way to catch up with and more than CRT display device, its excellent performance, mass production characteristics, a high degree of automation, the raw material cost is low, the vast room for development, will quickly become a new century mainstream product, is the 21st century global economic growth of a window.

Main features

And TN technology different is, TFT displays using "back through type" illuminate way -- imaginary light path is not like TN LCD that from go up to below, but from below. This approach is in liquid crystal back set special ray tube, illuminant irradiation time by partial plate under upward passes. Due to the fluctuation of interlining electrodes into an FET electrode and generic electrodes, in an FET electrode turn-on, liquid crystal molecules performance will change also, can pass shading and pervious to light to achieve the purpose of display, response time greatly improve to 80ms around. Due to its LCD higher than TN - the contrast and richer color, screen update frequency also faster, so TFT commonly known as "truecolor".

Relative to character, tft-lcd DSTN the main characteristic is for each pixel configure a semiconductor switching devices. Since each pixel can directly control through the point pulse. Thus each node is relatively independent, and available for continuous control. This design method not only improves the speed of response display screen, also can accurately control and display gray, this is DSTN more lifelike TFT colour is the reason.

application

At present, most of the laptop computer manufacturers products all adopt tft-lcd. Early tft-lcd mainly used for laptop manufacture. Although at that time DSTN TFT relative to a huge advantage, but because of technical reasons, tft-lcd in response time, brightness and visual Angle with the traditional CRT display also has the very big disparity. Add an extremely low yield resulted in its high price, which desktop's tft-lcd become unreachable fuck.

However, with the development of technology, roa unceasing enhancement, plus some new technologies to emerge, make tft-lcd in response time, contrast, brightness, visible Angle has made great progress, narrowing the gap with traditional CRT display. Nowadays, most mainstream LCD monitor response time are raised to 16ms below, all of these LCD towards mainstream paved the road.

LCD application should say is huge potential market. But just LCD panel production ability is concerned, the world's LCD mainly concentrated in China Taiwan, South Korea and Japan's three main production base. Asia is the LCD panel r&d and manufacturing center, and Taiwan, Japan, HanSanDa origin of development are different.

Mainstream TFT panel

Current main TFT face plate has a - Si (amorphous silicon TFT (thin film transistor) technology and LTPS TFT (low temperature polycrystalline silicon) TFT technology.

In a - Si aspects, three production base of technology is special. Japanese manufacturers have developed 256 x 2048 resolution as high as the LCD products. Therefore, some people think that a - Si TFT technology can fully satisfy high resolution product needs, however, because technology not mature, it is still not enough high-speed video image or animation etc needs. LTPS TFT relative ok and managing cost, this regarding the TFT LCD promotion has important significance. At present, the Japanese manufacturers have mass-production 12.1 inch TFT LCD LTPS ability. While China Taiwan developed LTPS LTPS components manufacturing technology and SXGA panel technology. South Korea in this respect lack of special design personnel and r&d experts, but as samsung mainly enterprise have introduced LTPS products, show the strength of the Korean firms. But now, LTPS technology is not mature, product concentrated in small screen, and roa low, there is no cost advantages from talking about.

Compared with LTPS, a - Si TFT LCD is undoubtedly at present the mainstream. Japanese company is a - SiTFT investment strategy on almost all to the third generation LCD products, through manufacturing technology and roa improvement to increase production and reduce the cost. Japan has been walking high-end course, its technology is undoubtedly the most advanced. Due to the r&d strength is limited, Taiwan's a - Si TFT technology mainly from Japanese manufacturers, but due to the transfer of Taiwan enterprises generally belongs to labor-intensive technology, price low, production the low-end products. South Korea in a - Si has strong r&d competence, such as samsung will mass-production global first 24-inch TFT LCD - a - Si 240T, its response time less than 25ms, can satisfy general application needs; While viewing angles reached 160 degrees, making the LCD in traditional weak do not lose to CRT. Samsung 240T marks the big screen TFT LCD technology maturity, and also to show the strength of the Korean firms is beyond doubt.

Tft-lcd market analysis

Tft-lcd is an active matrix liquid crystal display (LCD) AM the typical representative of the study, the most active, the fastest growing, application, the most rapidly growing also in notebook computer, video cameras and digital camera monitor, the application of coquettish, in addition, it in the geography information system and the cockpit, portable DVD, desktop computers and multimedia monitor all aspects to obtain the very good applications. Color tft-lcd idea at first by americans (Westinghouse) in 1972 proposed, Japanese Toshiba company in 1982 the lead in realizing this technique of the scale production, but then production technology still not mature. Since 1993 Japan mastered tft-lcd production technology by CGA outlets already since resolution (320 * 200) to today's UXGA (1600 * 1200), substrate sizes have first generation of 240 * 270-32O * 400mm2 development to Japan in 2001 sharp, samsung electronics and LG Philips company respectively the horse - seventh generation 13.5 * 1700 mm2. At present, the application of tft-lcd mainly in small size of the mobile phone market, medium size of PDA with notebook computer market, large size LCD monitor and LCD TV market such five aspects. 2005 tft-lcd will be mainly used in displays (39%), notebook computers (25%), cell phone (16%), liquid crystal TV (10%), PDA (6%) five areas, market sale amount will be more than 250 million us dollars, accounting for LCD market proportion more than 90%, become LCD and even the whole flat panel display technology leading technology.