Advantages: 1, low-voltage, micropower low operating voltage, as long as 2-3V, operating current of only a few microamps, the power consumption is only 10-6-10-5W / cm2, which is any other display devices I can not do. 2, the basic structure of the flat-panel liquid-crystal monitor two pieces of conductive glass, liquid crystal filling a thin middle-shaped box. A high numerical aperture most favorable as the display window display area B are more likely to expand a small C facilitates automated mass production of low production costs after only a few millimeters thin device D 3, passive display type liquid crystal itself does not light, modulated by the outside world Optical achieve display purposes, which rely on different external light reflection and transmission to achieve the formation of different contrast display purposes. LCD can not be displayed in the dark, but in the nature of human visual information obtained, more than 90LL% is light reflected by an external object, rather than the object itself light, so passive display more suitable for the human visual, it is not likely to cause eye fatigue. 4, the amount of information displayed in the LCD monitor, do not take quarantine measures between each pixel, so in the same display area can accommodate more pixels, made in favor of a high-definition TV displays. 5, easy to color of a general liquid crystal colorless, very easy to use color filters to achieve color. LCD can reproduce color CRT monitor can be comparable. 6, long life as long as the liquid crystal component parts are not damaged, the LCD itself due to the low operating voltage, current, so almost no deterioration, long life. 7, no radiation, no pollution CRT display X-ray radiation, PDP display has a high-frequency electromagnetic radiation, and liquid crystal display does not appear these problems. Disadvantages: 1, viewing angle small due to the principle of relying on most LCD anisotropy of the liquid crystal molecules of different incident light, the reflection rate is not the same, so a smaller viewing angle, only 30-40 degrees. As the viewing angle becomes large, the contrast deteriorate rapidly. 2, slow response LCD mostly rely on under an applied electric field, the arrangement of the liquid crystal molecules changes, so the response rate viscosity greatly influenced by the material. Response speed is generally 100-200ms, the lower the temperature, the slower the response speed, poor dynamic image quality. 3, the fear of high temperature heat will destroy the orientation of the liquid crystal layer, causing irreparable damage. Local temperature will form an afterimage. 4, due to non-self-luminous dark see what is crystal 2-2 fourth state of matter - liquid crystal substance we know there are three states: solid, liquid and gas. Usually solid was heated to the melting point of the liquid becomes transparent. However, some organic material not change directly from a solid to a liquid, but through an intermediate state, and then into a liquid. This intermediate state appearance hazy liquid fluidity, and also optically anisotropic birefringent crystal unique characteristics. In an intermediate state of matter, on the one hand like a liquid having fluidity and continuity, on the other hand has the same anisotropy as crystal, like this orderly fluid is a liquid crystal. Some parts of the basic structure of the different types of 2-3 pieces of LCD monitor LCD monitor member may be different, if not polarizing. But the two conductive glass holding a liquid crystal layer, sealing to the same basic structure of a flat box. If you need a polarizing plate, then attached to the outer surface of the conductive polarizing glass. 2-4 are three ways to explain the TN-type liquid crystal display of the TN-LCD of about 10um having positive dielectric anisotropy nematic liquid crystal rear (twisted nematic LCD monitor member) between the two conductive glass substrates charged (Np liquid crystal), liquid crystal molecules are aligned along the surface, but the molecular long axis between the upper and lower substrates are continuously twisted by 90 degrees, forming a twisted (TN) liquid crystal cells arranged. 1, the reflection type optical reflective outer can save power TN type (twisted nematic) liquid crystal devices typically operate in a reflective, the incident light first passes through the liquid crystal cell and then reflected by the reflector. The reflector consists of a diffuse reflector and a mirror composed, they adhere to the outer surface of the glass at the bottom. When two orthogonal polarizers, the device operates in a positive display, no power on time by the polarizer into linearly polarized light passes through the liquid crystal layer, the polarization direction through 90 degrees, just under the polarizer can be reached by reflector light reflected polarization has not changed, once again through the liquid crystal cell and the polarizing reach of the human eye. When coupled with a high enough voltage, liquid crystal molecules with an electric field parallel to the plane of polarized light rotation no longer happen, so light can not pass through the liquid crystal cell reaches the reflecting surface. Reflective even under direct sunlight will not be washed. However, when the background brightness in dark or high enough to observe a liquid crystal device, we need to add other artificial light. To do this often equipped with a light bulb at the edges of the diffuse plate. 2, a transmissive TN liquid crystal may operate in a transmissive polarizer above the liquid crystal cell is a linear polarizer. Below the linear polarizing plate analyzer. Their polarization axes parallel to each other, and are consistent with the liquid crystal molecules are aligned at the top surface of the substrate. When combined with external electric field (relaxation state) as the incident light to reach the bottom of the liquid crystal cell, the plane of polarization of the light will be analyzer polarization axis perpendicular to the light is blocked by the analyzer, the liquid crystal cell from the back at the past opaque, add After the external electric field, the rotation does not occur when the incident light through the liquid crystal cell, from passing through the analyzer, if the liquid crystal cell is transparent. So is the light transmissive liquid crystal on display after display modulation of the incident light. 3, projection another very rapid development in recent years of LCOS (LConSilicon) is a typical projection. In LCOS active matrix made directly on the silicon chip, the size can be made small, and can take full advantage of already very mature silicon integration process. It will be explained in the rear projection TV. Monitor Monitor is the standard output monitoring system, with the front-end to send monitors to watch over the images. Monitor sub-color, black and white, sizes 19,22,26,32,37,42,46,47,55 inch, commonly used is 26 inches. Monitors also have a resolution, like the camera with the line number indicates the general requirements for the monitor to match the number of lines and the actual use of the camera. In addition, some monitors there is an audio input, S-video input, RGB component input, etc., in addition to audio input monitoring system used, the remaining functions for most image processing. A performance difference, the difference between a monitor and a TV monitor on the TV function than simple but in performance, but requires more demanding than television, the main difference is reflected in the three "degrees." 1. Since the conventional television image clarity is received television emitted RF signals, the signal corresponding to the bandwidth of the video image is usually less than 6M, and thus the clarity of television lines typically greater than 400, requires a monitor with high image clarity, so professional monitor on channel circuit compared to traditional TV in terms of compensation and should have the bandwidth boost circuit, so that the pass band wider, higher image sharpness. 2. If the color reproduction of clarity is mainly composed of video channel amplitude-frequency characteristics of the decision, the reduction of the principal by the monitor in red (R), green (G), and blue color signal (B) three primary colors and the phase of the luminance signal is determined. Since the monitor is usually observed as a static image, and thus to monitor color reproduction of the requirements higher than the TV, put it as the professional channel monitors in brightness, color processing and R, G, B treatment should have Exact compensation circuit and a delay circuit to ensure that the light / color signal and R, G, B signal phase synchronization. 3. Monitor when the machine stability constitute CCTV, usually 24 hours a day, 365 days a year continuous uninterrupted electricity use (TV usually work only a few hours per day), and some application monitor environment It may be more severe, which requires higher reliability and stability of the monitor. In contrast, in the design, monitor current, power, temperature and resistance to electrical interference, capacity and margin electric shocks and MTBF use of time are much larger than the TV and TV, while the monitor must the use of fully shielded metal housing to ensure electromagnetic compatibility and interference performance; in the selection of components, all aspects of the characteristics of components pressure, current, temperature, humidity and other monitor uses are higher than TV using the components; and in the installation, commissioning, especially components and the aging process requirements, monitor requirements are higher, the TV manufacturing machine aging is usually in the pipeline for about eight hours at room temperature energized, and monitor the machine Aging is required on the aging line of high temperature, high humidity closed environment energized aging for more than 24 hours to ensure the stability of the machine. If you use the TV as a monitor terminal monitoring system, except possibly feel more blurred image (low-resolution, color fidelity is poor), the TV using the components without interruption claim is not suitable for continuous use. If forced to use the TV as a monitor. Ranging prone to failure, severe cases may be due to the high operating temperature of the TV and cause an accident. Two, CRT monitors and LCD monitors use a cathode ray tube performance difference (CRT) color monitors and liquid crystal display (LCD) color monitor on the image reproduction principle is different, the former uses magnetic deflection drive to achieve horizontal and vertical scan mode (also known as analog driving mode), while the latter uses a dot-driven approach (also known as digital drive mode). Thus the former tend to use TV line to define its clarity, while the latter is defined by the number of pixels resolution. Definition CRT monitor dot pitch and convergence errors are mainly channel bandwidth and CRT monitors decisions, the latter by the number of pixels used in LCD screens decision. CRT monitor has a low price, high brightness, wide viewing angle, higher life advantages, but there are small LCD monitors (flat-shaped), light weight, the advantages of no radiation, flicker-free images, but LCD monitors The main disadvantage is the high cost, narrow angle (side view when the image is darkened, color drift occurs worse inverse), life is short (typically LCD screen burn-in after 5000 hours its brightness reduced to 60% below normal brightness, but CRT's average life expectancy up to 30,000 hours) and other shortcomings. Of course, LCD flat panel display device as a most sophisticated leading-edge products, has been more and more attention of domestic and foreign manufacturers, whose technology is constantly progress. 2008 new thin-film product body horizontal viewing angle in-plane switching technology (TFT) LCD screen technology has up to 160 °, vertical viewing angle is up to 140 °; at the same time, the price of LCD screen will be gradually as the product of gradually rising popularity and production gradually decreased; LCD's life will continue to progress with the LCD backlight and liquid crystal materials technology improves. LCD monitor is entirely possible to replace CRT monitors monitor the market to become mainstream products.