At present, most liquid crystal displays on the market adopt 6BIT panels. Here, I'd like to introduce the difference between 6BIT and 8BIT. LCD has three color channels R,G,B G and B. When each channel can achieve 256(2 to the 8th power) grayscale display without the compensation of acquired technology, that is, 256*256*256 is equal to 16.7M color, we call such a panel 8BIT panel. While 6BIT can only display 64*64*64 gray scales, and finally, it can display 16.7M color through hardware dithering and other technical means, so 6BIT's panel can't compare with 8BIT in color. The 8BIT panel has three main features: high contrast, wide viewing angle and relatively slow response time. At present, panels on the market are divided into three categories according to their technologies, VA, IPS and TN, among which VA is divided into MVA and PVA,MVA is a technology of Fujitsu, while PVA is a further development and continuation of Samsung's MVA technology. IPS is a liquid crystal technology developed by Hitachi, which can greatly improve contrast and viewing angle, and increase the degree of color restoration. Therefore, the panels manufactured by the above two technologies must be regarded as 8BIT panels, and the last one is TN technology, which is a cheap synonym. Although its viewing angle is small, the viewing angle becomes larger immediately by sticking a wide viewing angle compensation film on the TFT－LCD surface. In addition, as TN panel is a typical 6BIT panel, the number of color displays is relatively small, so the response time of gray scale is usually faster. Wide viewing angle+super fast response time+low price, most consumers are attracted by this. Seeing this, everyone should understand that buying LCD is not only to judge its quality by the response time, but also the color is a very important factor.
Ips, pva, mva and tn. The first three are new panels, which are characterized by good color (8bit) and large viewable area (double 178 degrees), but the response speed is slightly slower. Type tn is a traditional panel commonly used in computer monitors nowadays, which is characterized by economy and fast response, but its color (6bit) and visible area are not as good as the above-mentioned new panel. The first three types are used for large screens. As we all know, the low cutting cost of TN LCD panel makes LCD display popular rapidly. However, because some users have a high demand for LCD color, they scoff at TN LCD and think that the performance difference between TN LCD panel and VA and IPS LCD panel is not the same level. So, is this really the case? In fact, this issue has been discussed countless times. Below, we will elaborate on some misunderstandings arising from our previous discussion, and hope that everyone will know more about the differentiation of LCD panels.
1. Viewpoint 1: TN panel itself can only display 16.2M colors, but can't really display 16.7M colors. Only the VA or IPS panel can really display 16.7M colors. For this view, we can think it is correct or wrong. Why do you say that? The reason why it is correct is based on the physical material structure of liquid crystal panel: from the physical structure of TN liquid crystal panel, it can only display 16.2M colors at the maximum; From the point of view of VA or IPS panel material LCD panel itself, they can be complete. The principle of liquid crystal color display is that there are three filter bands which only transmit red, green and blue light at the position corresponding to each pixel on the backlight panel, and each band of each pixel has an independent circuit to drive the liquid crystal molecules at the corresponding positions to rotate, so that red, green and blue lights with different brightness are mixed, and the human eye can feel various colors. When the voltage is high, the angle will be large, and when the voltage is low, the angle will be small, which is stepless regulation. The driving voltage can be divided into 2n parts from the highest to the lowest, so that the liquid crystal can display N-bit colors. Therefore, they think that there is no such thing as how many bit colors a board can only support. For any LCD panel, only how many bits are added to drive the color display. That is to say, regardless of TN or wide viewing angle panel, if 6bit IC is loaded, its color number is 16.2M (after dithering), and if 8bit IC is loaded, its color number is 16.7m. This is a theoretical statement, but Samsung SDI is 16.7M color based on 6bit IC. We will elaborate on this topic for you in future articles. Viewpoint 2: The color difference between 16.2M color and 16.7M color is discussed, so what is the difference between TN material and VA or IPS material LCD panel in color display for our naked eyes? Actually, the biggest difference between TN panel and VA or IPS panel is the color fading phenomenon caused by different viewing angles. We can simply look at the principle of PVA panel wide-angle technology: PVA wide-angle technology also belongs to the category of VA technology. In fact, it is very similar to MVA, which can be said to be a variant of MVA. The transparent ITO layer of PVA is used to replace the bumps in MVA, and the manufacturing process is compatible with TN mode. Transparent electrodes can obtain better aperture ratio and minimize the waste of backlight. After all, PVA and MVA are in the same strain, and both of them are equivalent in actual performance. PVA also belongs to NB (normally dark) mode liquid crystal. When the TFT is damaged and failed to receive electricity, the pixel appears dark. This mode greatly reduces the possibility of "bright spots" in the LCD panel.
