What is a screen display
Author:Zhang Jian Time:2021-08-05 16:51 Browse(912)
LCD screen of display
LCD is divided into a, B, C and a +. A screen is generally the best one.
as the name suggests.

What is a screen display

LCD is the hardware that uses LCD to display all kinds of graphics and colors.
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what is LCD<
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liquid crystal is a kind of almost completely transparent material.
its molecular arrangement determines the path of light through liquid crystal.
until the 1960s, it was found that charging liquid crystal would change its molecular arrangement, and then cause the distortion or refraction of light, This led to the idea of inventing liquid crystal display device.
liquid crystal display for short.
the world's first liquid crystal display device appeared in the early 1970s.
it was called TN-LCD (twisted nematic) liquid crystal display.
even if it was monochrome display.
it was still promoted to electronic watch, electronic display, electronic display and electronic display In the 1980s, STN-LCD (ultra twisted nematic) liquid crystal display appeared, and TFT-LCD (thin film transistor) liquid crystal display technology was developed, but the liquid crystal technology is still immature and difficult to popularize.
in the late 1980s and early 1990s, Japan mastered the production technology of STN-LCD and TFT-LCD, The LCD industry began to develop rapidly.
TFT (thin film transistor) LCD is a kind of active matrix liquid crystal display (am-lcd).
different from TN technology,
TFT display adopts "back transparent" illumination mode, which means the imaginary light source path is not from top to bottom like TN liquid crystal,But from the bottom to the top.
in this way, a special light tube is set on the back of the liquid crystal.
when the light source irradiates, it is transmitted upward through the lower polarizing plate.
because the electrodes of the upper and lower interlayer are changed into FET electrodes and common electrodes.
when the FET electrode is turned on, the performance of liquid crystal molecules will also be changed, and the display purpose can be achieved by shading and transmitting light, The response time is greatly improved to about 80 ms.
because it has higher contrast and richer colors than TN-LCD.
the screen update frequency is also faster, Therefore, TFT is commonly known as "true color."
compared with DSTN,
the main feature of TFT-LCD is that each pixel is equipped with a semiconductor switching device.
because each pixel can be directly controlled by a point pulse.
therefore, each node is relatively independent and can be continuously controlled.
this design method not only improves the response speed of the display screen.
but also improves the display performance The color of TFT is more lifelike than that of DSTN.
at present.
most notebook manufacturers use TFT-LCD.
the early TFT-LCD is mainly used in the manufacture of notebook computers.
although TFT has great advantages over DSTN at that time.
however, due to technical reasons, TFT-LCD has the advantages of high response time, low cost and low cost There is still a big gap between the brightness and visual angle of the desktop TFT-LCD and the traditional CRT display.
the extremely low yield leads to its high price.
however.
with the continuous development of technology, the yield continues to improve, and some new technologies appear,The TFT-LCD has made great progress in response time, contrast, brightness and viewing angle, and has narrowed the gap with traditional CRT displays.
nowadays.
the response time of most mainstream LCD displays has been improved to less than 50ms, All of these pave the way for LCD to go mainstream.
the application market of LCD should be said to have great potential.
however, in terms of LCD panel production capacity.
the world's LCD is mainly concentrated in three major production bases, namely Taiwan, South Korea and Japan.
Asia is the center of LCD panel R & D and manufacturing.
while Taiwan, Japan and Japan are the main production bases of LCD panel At present, the mainstream TFT panels are a-Si (amorphous silicon thin film transistor) TFT technology and LTPS TFT (low temperature polycrystalline silicon) TFT technology.
in the aspect of a-Si.
the technologies of the three production bases have their own merits.
Japanese manufacturers have developed resolution up to 2560 × Therefore, some people think that a-Si TFT technology can fully meet the needs of high-resolution products. However, due to the immaturity of the technology, It can not meet the needs of high-speed video image or animation.
LTPS TFT can save cost relatively.
this is of great significance for the promotion of TFT LCD.
at present.
Japanese manufacturers have the ability to mass produce 12.1 inch LTPS TFT LCD.
while Taiwan, China has developed LTPS component manufacturing technology and LTPS SXGA panel technology.
South Korea lacks special designers in this aspect However, major companies such as Samsung have launched LTPS products,It shows the strength of Korean manufacturers.
however.
at present, LTPS technology is not mature, and its products are concentrated in small screens with low yield, Compared with LTPS,
a-Si is undoubtedly the mainstream of TFT LCDs.
the investment strategies of a-Si TFTs of Japanese companies are almost all based on the third generation LCD products.
the output is increased through the improvement of manufacturing technology and yield, To reduce costs.
Japan has been taking the high-end route.
its technology is undoubtedly the most advanced.
due to the Limited R & D force.
Taiwan's a-Si TFT technology mainly comes from the transfer of Japanese manufacturers, but because Taiwan's enterprises are generally labor-intensive, the technology content and price are low, South Korea has a strong R & D strength in a-Si.
for example, Samsung mass produced the world's first 24 inch a-Si TFT lcd-240t, with a response time of less than 25ms, which can meet the needs of general applications; And the viewing angle reaches 160 degrees, which makes LCD not inferior to CRT in traditional weakness.
Samsung 240t marks the maturity of large screen TFT LCD technology.
it also shows the world the strength of Korean manufacturers without doubt.
in addition to the competition between the above two TFT technologies.
sed will become a powerful enemy of TFT LCD.
however.
sed is still a concept product, It is difficult to enter the mainstream market in a short period of time.
although LCD has been greatly reduced at present, the price is still higher than that of CRT.
therefore, the cost issue is the focus of attention.
in fact.
the price of LCD is higher than that of CRTThe production cost of TFT is the same as that of CRT, However, the low yield leads to the high cost of TFT panel.
TFT panel is cut from a large substrate.
LCD products also need a large number of transistor arrays to control the three primary colors.
the current manufacturing technology is difficult to ensure that tens of millions or even hundreds of millions of transistors on a large substrate do not have a problem.
if there is a problem with a transistor.
then that is the case The corresponding color of the point corresponding to a transistor will have problems (only certain fixed color can be displayed), so this point is commonly known as "bad point"
the probability of bad point occurrence depends on the location.
therefore, a substrate is likely to be wasted a lot.
at present, the general LCD requires less than 5 bad points.
however, some large manufacturers have reduced the standard to 3 or even 0, This will reduce the rate of good products.
and some small factories will expand the number of bad products.
in this way, the cost will naturally drop sharply, and the product quality will decline, This is one of the reasons why some manufacturers can significantly reduce the price of LCD.
although many manufacturers have the ability to produce LCD at present, only a few manufacturers have the ability to manufacture TFT panels.
Acer is a well-known enterprise in the IT industry.
although Acer has no ability to produce TFT panels, it has a close relationship with Taiwan Daji, However,
limited to the technical strength of Taiwan enterprises, Acer LCD products are mainly concentrated in the middle and low end.
Philips is a world-famous manufacturer of display equipment.
its display sales have been among the top in China, and it has reached an alliance with LG in South Korea to jointly develop and manufacture TFT panels.
Philips is a world-famous manufacturer of display equipmentSimilarly, due to technical reasons and market positioning problems, Philips products are mainly concentrated in the middle end, and the action of Philips in the retail market has not been very obvious.
Samsung, as another powerful R & D and manufacturer of display equipment,
has invested a lot of energy in LCD, and is committed to continuously enriching its product line, At present, Samsung products cover high, middle and low-end markets.
LCD technology is still in the stage of continuous development and improvement.
the development directions of the three major producing areas are different, and there are both competition and cooperation between them.
it is these factors that promote the development of LCD.
reference materials: http://www.g-ym.com/bbs/printpage.asp?BoardID=124&ID=1901.
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