LCD (liquid crystal display) uses the latest full-color display technology, and the principle is simple and easy to understand. Basically, the concept of the whole liquid crystal display technology is to use the physical characteristics of liquid crystal: when powered on, the arrangement becomes orderly, so that light can pass easily; When there is no electricity, the arrangement is disordered to prevent light from passing through. Let the liquid crystal block like a gate or let light pass through. In terms of technology, the liquid crystal panel contains two rather exquisite sodium free glass materials, called substrates, with a layer of liquid crystal sandwiched between them. When the light beam passes through this layer of liquid crystal, the liquid crystal itself will stand or twist in an irregular shape, so as to block or make the light beam pass smoothly.
Compared with CRT display, LCD overcomes the disadvantages of large volume, power consumption and flicker of CRT, but it also brings some problems, such as high cost, poor viewing angle and unsatisfactory color display. However, technically speaking, the advantages of LCD are still obvious, and the specific performance is as follows:
- Smaller volume and lighter weight
Due to the use of picture tube technology for imaging, the traditional CRT display needs to contain a vacuum picture tube, and then equipped with an electron gun at the tail end, so that its length generally exceeds 30 cm, and the volume of the whole display is of course larger. For example, the liquid crystal display is made of liquid crystal materials, and then the corresponding imaging technology is used to achieve the display purpose. There is no need to install a picture tube inside the display. Of course, the volume is small. For example, the volume of EMC’s 15 inch liquid crystal display bm-568 is only one-half to one-third of the volume of 19 inch CRT display, which has great elasticity when placed, Of course, its small volume also greatly reduces its weight.
- Larger relative display area
Due to the limitation of display technology, the size of traditional CRT display is smaller than the display area of fluorescent screen. Generally, a 15 inch CRT display, although the size is 15 inches, its real visual range may only be about 14.1 inches, while a 17 inch display may only have a display area of 15 to 16 inches below it. However, due to the different surface image principle of LCD, the size marked is the actual display area. For example, the display area of Samsung’s 15 inch LCD is completely 15 inches, which is equivalent to the display area of a 17 inch CRT display. If the price difference between the two is not much, of course, it is much more cost-effective to buy a LCD.
- Zero radiation, no flicker
CRT display adopts cathode picture tube for imaging. The electron beam contained in it will produce a lot of static electricity and radiation when moving. The faster the electron beam runs, the greater its radiation. Long term use of human body will cause damage to eyes and skin, resulting in myopia, skin allergy and other problems. Because the liquid crystal display adopts liquid crystal materials, there is no need to use electronic beams during operation, so there are no problems affecting vision such as static electricity and radiation. In addition, the formation of a picture of CRT display is formed through horizontal scanning. There is no flicker only when the scanning frequency reaches a certain value. LCD does not need any scanning process. A picture is formed almost at the same time. Even if the refresh frequency is very low, there will be no flicker.
- Low power consumption and strong anti-interference ability
In addition to the circuit and image power consumption, CRT displays also have the power consumption of the display screen, while LCD displays are mainly backlight and circuit power consumption, and the power consumption of the display screen is negligible. For example, the power consumption of EMC’s 15 inch display bm-568 is only 35 watts, which is nearly 50% less than that of CRT products with the same display area. In addition, unlike CRT display, LCD is not imaged with color picture tube and electron gun. It does not need to consider the high radiation impact caused by improving the electron beam emitted by the electron gun, but only obtains the brightness through the backlight emitted by the fluorescent tube. Therefore, it has stronger anti-interference ability, and will receive good display effect even in the environment with concentrated light.
- Higher picture quality
The traditional CRT display adopts the analog display mode, and the signal output of the display card adopts the analog output mode, which may cause the loss of image and the decline of image quality in the transmission process, while the signal transmission of the LCD adopts the digital mode, which is that the display card directly inputs countless word signals, which will not cause the loss of signals, However, at present, most LCD still adopts VGA interface for analog display, and only a few manufacturers such as EMC, Samsung and Acer have set up digital video signal interface.
- The use function is more intelligent
Due to the different materials and technologies used in LCD, some of its parameters are generally fixed, which requires more intelligent performance adjustment of LCD. In this regard, each manufacturer has its own mature technology. Generally speaking, there are two main types. One is similar to EMC auto set automatic adjustment and optimal setting function, as long as one of the parameters is adjusted, Other parameters are automatically adjusted to the corresponding values and are the best values to ensure the best display effect. The other is the single key recovery function, that is, one key is prefabricated, and all parameters can be changed back to the preset settings at the factory with one