Monday, December 27, 2010
【 Weak current College 】 LCD bad/spotlight on the causes and prevention of 】
A constitutive principle, LCD
The LCD looks only one screen plate, in fact, it mainly consists of four main blocks (filters, polarizing plate, glass, cold cathode fluorescent lamp) combination, here to you simple to elaborate.
Filter: TFTLCD Panel's ability to produce colour changes, mainly from color filter, LCD Panel is through the driver's voltage change, so that the liquid crystal molecules line stand, display, and the color of the screen itself is black and white, pass filter-rays can be transformed into color pattern.
Polarizer: polarizer can be converted to a linear polarizer natural light, where performance is the incidence of linear optical polarizing separation of constituent parts, one part is making it through to the other part is absorbing, reflector, scattering functions make it hidden, reduce brightness/bad points.
Cold cathode fluorescent lamp: characterized by small, high brightness, long life. Cold cathode fluorescent lamp by a special design and processing of glass and can quickly after repeated use of light, can withstand up to 30000 switch operation. Because of the cold cathode fluorescent lamps use trichromatic Phosphors, so their luminous intensity increases, the light attenuation, color-change quality is good, so heat generated is extremely low, the effective protection of the life of the LCD screen.
Second, the LCD Brightness/bad point causes and prevention
1. the manufacturer's reasons:
Bright/bad point is also called LCD bright spot, is a type of LCD a physical injury, is mainly due to the bright spot in parts of the screen outside the internal reflection plate subjected to oppression or heating a slight deformation.
LCD screen of each pixel has a red, green and blue primary colors, their common combination makes pixels produce of various colors. To 15-inch LCD monitor, for example, the LCD area 304.1mm * 228.1mm, resolution of 1024 * 768, each RGB RGB pixels by liquid crystal modules. LCD pixels is the LCD into the fixed mould formation of liquid crystal cell under, such as 15 inches liquid crystal cell of the quantity on the LCD monitor is 1024 * 768 * 3 = 235 000! a liquid crystal cell size and? we can simply computing: high = 0.297mm, width = 0.297/3 = 0.099mm! — that is, in the area of 304.1mm * 228.1mm closely arranged under 235 000 area only 0.297mm * 0.099mm size LCD box, but also in liquid crystal cell behind also integrated a separate drive the LCD driver box. Obviously, this kind of production process on the production line requirement is very high, with current technologies and processes, also cannot guarantee that each batch produced LCD without/bad point, manufacturers typically avoid bright/bad point to split flat plate, without/pixel or very few bright/pixel LCD high supplies powerful manufacturers, while those who lit/bad points more LCD are generally low supply small manufacturers producing cheap LCD monitor.
Technically, bright/bad point is the LCD Panel is not fixed pixel, is in the production process. LCD display panel consists of a fixed LCD pixels, in the size of the LCD pixel 0.099mm behind three transistors, corresponding to red, green, blue filter, any one transistor problems i.e. short circuit will make the pixels into a bright/bad points. Also, each LCD pixels behind also integrated a separate drive its micro drive pipe. If the red-green-blue color in one or more generating a fault, then the pixel is not normal that changes color and will become a fixed color dots under certain background color will be obvious to see that this is the LCD bright/bad points. Bright/bad point is the LCD screen in the production and use is not 100% avoided a physical injury, the majority of cases it produces to the screen at the time of manufacture, in use impact or natural wear and tear can lead to lighter/bad points. As long as the composition of a single pixel of color in one or more corrupted, bright/bad points will resultin the production and use are likely to cause damage.
We all know that, in accordance with international practice, the LCD monitor has three following lit/bad point is allowed, however no consumer may wish to purchase the LCD is going to buy one with lighter/pixel monitor, and therefore generally have lit/pixel LCD manufacturers are difficult to sell. In the face as the cause of the production process has three or more and even more brilliant/bad point of Panel manufacturers are going to do with it? in order to get benefits, some manufacturers do not abolish the LCD, in most cases these panels use a professional equipment on bad lit/bad point, bring it on the surface to the naked eye watch no bad lit/bad points. There is also a small number of manufacturers do not even deal with direct input into the Panel production line for production, so as to achieve the aim of reducing costs. These products are really good at prices above advantages, but use will soon produce light/bad points. Market, many inexpensive LCD is processed, so you're buying a LCD monitor's time don't be just for the sake of cheap, buy some unknown brands. Glad I bought a cheap zero bright. Because it won't be long before, you don't want to see things may happen eventually.
2. reasons for using process
There are LCD lit/bad points may be used in the process, simply to say that usually use some considerations when:
(1) do not install multiple systems simultaneously; after install multiple systems during the switching will cause the LCD to some extent of the damage.
(2) maintain normal voltage power,
(3) do not touch the LCD button at any time.
These three points are directly or indirectly affect "LCD box" elements functioning, which may cause light/bad points. Consumers in the use process appears bright/bad point, actually passLive detection of engineers know what causes it, I want to go to the manufacturer as long as not to hurt them a conscience, even on theconsumer/bad point consumers are understandable.