Panels are also different. Analysis of LCD panel technology

The LCD panel is the screen of the LCD monitor. Its production, quality, market environment and other factors are related to the quality, price and market trend of the LCD monitor itself, because about 80% of the cost of an LCD monitor is concentrated on the panel.

Although the panel is the main factor, the quality of the control circuit and optimization technology also directly affects the display quality, which is manifested as color differences. The same picture will appear different on different panel displays.

At present, there are three types of mainstream LCD monitor panels in the market, namely: VA, IPS and TN. They have their own liquid crystal materials and panel structures, and their advantages and disadvantages are also different.

1. TN panel

TN stands for Twisted Nematic panel. The low production cost makes TN the most widely used entry-level LCD panel. It is widely used in the mainstream low-end and mid-range LCD monitors on the market. Most of the TN panels we see are improved TN+film, where film is the compensation film, which is used to make up for the lack of viewing angle of TN panels. Currently, the viewing angle of improved TN panels reaches 160°. Of course, this is the limit value measured by the manufacturer under the contrast ratio of 10:1. In fact, when the contrast ratio drops to 100:1, the image has already been distorted or even color cast.

The advantage of TN panel is that due to the smaller number of output gray levels, the liquid crystal molecules deflect quickly and the response time can be easily improved. TN panel is a soft screen and similar water ripples will appear if you gently scratch it with your hand.

2. VA panel

VA panels are the most widely used panel type in high-end LCDs, and they are wide-viewing angle panels. Compared with TN panels, VA panels can provide 16.7M colors and a wide viewing angle, which is the capital of this type of panel positioning at the high end, but the price is also relatively more expensive than TN panels. VA panels can be divided into MVA panels led by Fujitsu and PVA panels developed by Samsung, of which the latter is the inheritance and improvement of the former. VA panels have the highest front (front view) contrast, but the uniformity of the screen is not good enough, and color drift often occurs. Sharp text is its killer feature, and the black-and-white contrast is quite high.

Fujitsu's MVA technology (Multi-domain Vertical Alignment) can be said to be the earliest wide-viewing angle LCD panel technology. This type of panel can provide a wider viewing angle, usually up to 170°, and the grayscale response time can be less than 8ms.

Samsung's PVA (Patterned Vertical Alignment) technology also belongs to the category of VA technology. It is the successor and promoter of VA technology. Its comprehensive quality has surpassed the latter in all aspects, and the improved S-PVA can keep pace with P-MVA, achieving extremely wide viewing angles and faster and faster response times. PVA uses transparent ITO electrodes to replace the liquid crystal layer protrusions in MVA. The transparent electrode can obtain a better aperture ratio and minimize the waste of backlight. VA panels are also soft screens, and similar water marks will appear if you gently scratch them with your hand.

3. IPS panel

IPS (In-Plane Switching) technology is a liquid crystal panel technology launched by Hitachi in 2001. IPS technology is currently used by manufacturers such as Philips, LG, and AOC, but there are not many models available on the market. The biggest feature of IPS panels is that its two electrodes are on the same plane, unlike other liquid crystal modes where the electrodes are arranged in three dimensions on the upper and lower surfaces. Since the electrodes are on the same plane, the liquid crystal molecules are always parallel to the screen regardless of the state, which will reduce the aperture ratio and light transmittance, so IPS applications on LCDs require more backlights.

The advantages of IPS panels are high viewing angle, fast response speed, accurate color reproduction, and low price. However, the disadvantages are serious light leakage and insufficient black purity, which is slightly worse than VA, so it is necessary to rely on optical film compensation to achieve better black.

Compared with other types of panels, the screen of IPS panel is relatively "hard". It is not easy to deform like water pattern when you scratch it with your hand, so it is also called hard screen. If you look closely at the screen, if you see fish scale-like pixels facing left and hard screen, then you can be sure that it is an IPS panel.