Basic Introduction of LCD segment code LCD screen
1 brightness LCD is a substance between solid and liquid, which itself cannot emit light, additional light sources are required. Therefore, the number of tubes is related to the brightness of LCD. The earliest liquid crystal display has only two lamps, up to now, the lowest universal type is also four lamps, and the high-end is six lamps. The four-lamp design is divided into three placement forms: one is that there is one lamp on each of the four sides, but the disadvantage is that there will be a shadow in the middle. The solution is to arrange the four lamps horizontally from top to bottom, the last one is the 'U' type of placement, which is actually two lamps produced by two lamps in disguised form. The design of the six tubes actually uses three tubes. The manufacturer bends the three tubes into a 'U' shape and then places them in parallel to achieve the effect of the six tubes. 2 The Control IC, filter, orientation film and other accessories selected in the manufacture of contrast LCD are related to the contrast of the panel. For ordinary users, the contrast ratio of 350: 1 is enough, however, such a contrast level in the professional field cannot meet the needs of users. Compared with CRT monitors, which can easily reach a contrast ratio of 500: 1 or even higher, only high-grade liquid crystal displays can reach such a level. On the market, Samsung, Asus, LG and other first-line brands can reach the level of 1000: 1 contrast today, but it is difficult to accurately measure the contrast by instruments, therefore, when choosing, you still have to see it yourself. 3 Visual angle the viewing angle of LCD is a headache problem. When the back light source passes through the bias plate, liquid crystal and orientation layer, the output light has directivity. That is to say, most of the light is emitted vertically from the screen, so when viewing the LCD from a large angle, you cannot see the original color, or even only all white or all black. In order to solve this problem, manufacturers have also started to develop wide-angle technology. So far, there are three popular technologies, tn film and IPS (IN-PLANE-SWITCHING)And MVA (MULTI- domain vertical alignMENT). 4 Signal response time, the response time refers to the response speed of the liquid crystal display to the input signal, that is, the reaction time of the liquid crystal from dark to bright or from bright to dark (Brightness from 10%-->90% or 90%-->10% of the time), Usually in milliseconds (ms)Is the unit. To clarify this point, we should also talk about the human eye's perception of dynamic images. There is a phenomenon of 'visual residue' in human eyes, and high-speed moving pictures will form a short impression in human brains. Cartoons, movies and so on, until now, the latest games just apply the principle of visual residue, making a series of gradual change images display rapidly and continuously in front of people's eyes, thus forming dynamic images. The display speed of pictures that people can accept is generally 24 pictures per second, which is also the origin of the playback speed of movies at 24 frames per second. If the display speed is lower than this standard, people will obviously feel the pause and discomfort of the picture. According to this indicator, the display time of each screen needs to be less than 40 MS. In this way, for the liquid crystal display, the response time of 40ms becomes a barrier, and the display above 40ms will have obvious picture flicker, which makes people feel dizzy. If you want the image to be non-flashing, you 'd better reach a speed of 60 frames per second.