Introduction In general, refers to a display monitor, and some dual monitor graphics card can output, another is called the monitor. Monitor the development of experienced black and white to color, from blinking to not blinking, and then the development of BSV LCD technology from CRT (cathode ray tube) to the LCD (liquid crystal). Monitor as an important application products, various types of monitors emerging, LCD (LCD), plasma (PDP), a light-emitting diode (LED) technology, monitors, etc. advanced products have been widely used. 2 Application monitor as a display terminal closed-circuit monitoring system is in addition to the camera monitoring system outside an integral part. For a long time the monitor is mainly used in finance, jewelry stores, hospitals, subway, train stations, airports, exhibition of the commercial office, leisure and entertainment, etc., responsible for the security aspects. The development of technology, the entire cost of closed-circuit surveillance system has been well adjusted. More and more small businesses also have affordability, began to build their own monitoring system to achieve security or other monitoring needs. Monitor picture Monitor Picture 3 points classification by size: LCD monitor into 8/10/12/15/17/19/20/22/24/26/32/37/40/42/46/47/52 / 57/65/70/82/108-inch monitors. Divided by color: color, black and white monitor. Press Scan points: interlaced and progressive scan. By type: all-aluminum LED monitors, LCD monitors, rear projection, CRT monitors, plasma monitors. The screen points: flat, puping, spherical and so on. Material: CRT, LED, DLP, LCD and so on. According to zoning: security monitor, monitor monitors, radio and television monitors, industrial monitors, computer monitors. 4 distinguish the difference between a monitor and a TV monitor in function than the TV simple but in terms of performance, but it requires more demanding than television, the main difference is reflected in the three "degrees." Since the conventional image definition television receiving stations is emitted RF signals, the signal corresponding to the bandwidth of the video image is usually less than 6M, thus HDTV is typically greater than 400 lines, require the monitor has a high image clarity degree, so the professional circuit monitors the channel than traditional TV should have the bandwidth in terms of compensation and boost circuit, so that the pass band wider, higher image sharpness. If color reproduction clarity primarily by video channel amplitude-frequency characteristics of the decision, then the degree of reduction is mainly by the monitor in the red (R), green (G), and blue (B) three-color chromaticity and luminance signal phase of the signal is determined. Since the monitor is typically observed as a static image, and thus the color reproduction of the monitor is higher than the TV request, so as the professional monitor discharge passage in brightness, chroma processing and R, G, B should have treatment Exact compensation circuit and delay circuit to ensure the light / color signal and R, G, B signal phase synchronization. Color LCD monitor has been concerned about people, many manufacturers have made 16.2M and 16.7M these two criteria, these two standards can reflect the intuitive color reproduction capability of the LCD monitor. If the color of the LCD monitor more stringent requirements, it is the best option with the product 16.7M in. Monitor machine stability when composing CCTV, usually 24 hours a day, 365 days a year of continuous uninterrupted electricity use (and the TV is usually only a few hours a day of work), and some monitors application environment may be more poor, which require 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 the TV, but you must also monitor the use of fully shielded metal housing to ensure electromagnetic compatibility and interference performance; in the selection of components, various components of the voltage characteristics, current, temperature, humidity, etc. used to be higher than the TV monitor using components; and in the installation, commissioning and machine components, especially the aging process requirements, the monitor is also higher, when TV manufacturing machine aging is usually on the line is energized about 8 hours at room temperature, and monitor the machine Aging is required on the aging pipeline temperature, humidity closed environment energized aging more than 24 hours, in order to ensure the stability of the whole machine. From the above analysis shows that, if you use the TV as a monitor terminal monitoring system, except possibly feel more blurred image (lower resolution, color fidelity is poor), the TV using the components do not fit no intermittently require continuous use. If forced to use the TV as a monitor. Ranging from easy-to-failure, severe cases may be due to the high operating temperatures of the TV and cause an accident. The difference between CRT and LCD monitors use a cathode ray tube (CRT) and liquid crystal color monitor display (LCD) color monitor on the image to reproduce the principles are different, the former driver realized using magnetic deflection field scanning way (also known as simulation-driven approach), while the latter uses dot-driven approach (also known as digital-driven approach). Thus the former tend to use TV lines to define its clarity, while the latter is defined by the number of pixels resolution. Resolution CRT monitor is mainly determined by the channel bandwidth is narrow and the pitch and convergence errors tube monitor, and the latter by the number of pixels of the LCD screen using decision. CRT monitor with a low price, high brightness, wide viewing angle, high service life advantages, but there are small LCD monitor (flat-shaped), light weight, the advantages of no radiation flicker-free images, but LCD monitors The main disadvantage is the high cost, narrow viewing angle (when viewing the image darker side, anti-color color drift appear worse), life is short (usually LCD screen burn-in after 5000 hours at 60% brightness drop below normal brightness, but The average life expectancy of up to CRT 30,000 hours) and other shortcomings. Viewing area at the time of purchase of the LCD monitor, the first consideration is the "face" in size. For the LCD monitor, its size of the panel is the size of the viewing area, which is a little different with the CRT monitor. Specifications of the same monitor, bigger than the CRT LCD viewing area some, usually the equivalent of 17 inches 15 inches LCD CRT, 17-inch LCD with the equivalent of 19 inches CRT, which is equivalent to 21 inches 19 inches LCD CRT. LCD Monitor 20 inches, 32 inches and 40 inches in three sizes, 20 inch 4: 3 display mode; 32 and 40 inches for the 16: 9 display mode. Response time is the biggest selling point of the LCD monitor and improve the response time of 25ms from the beginning to now gray 4ms, faster fast breathtaking. Response Time Monitor can determine the picture frames displayed per second, faster than usual when the screen displays 25 frames per second, the human eye will quickly transform the screen as a continuous screen. In high-speed ball running, screen-speed switching / time to move, to achieve the best results, you need the screen display speed of 60 frames per second or more, the response time of 16ms or more to meet the requirements, that is, the response time is smaller, fast The effect of changes in the display screen of the more perfect. The market mainstream LCD monitor response time is 8ms, cost is also very high, up to 125 frames per second display rate, comparable with a CRT monitor. No excessive demands for the number of consumers to say, 12ms, 16ms product is a good choice, conventional fixed cameras, speed dome camera image significantly depending fully met. Contrast LCD is a substance that is between the liquid and the crystal itself does not emit light, so the backlight brightness determines its brightness. In general, the higher the brightness of the LCD monitor, the more vivid color display, real effect is better. LCD monitor brightness expressed in units of cd / m (lumens), the general brightness of the LCD monitor is 250cd / m. If the brightness is too low, the displayed color will dim to see for a long time will feel very tired. Contrast is the ratio of brightness, that is, in a dark room, divided by the brightness of the white screen at black screen brightness under. Therefore, the brighter white, black, the darker, the higher the contrast, the more clear and bright screen display, the stronger the color layering. General contrast LCD monitor 300: 1, some of the better up to 400: 1 or more, while the traditional CRT monitor can be up to 500: 1. If the contrast is less than 250: 1, we will have a fuzzy feeling when you look at the screen. For weather monitoring projects, high-brightness / high contrast LCD monitor is the most appropriate choice. Of course, not the brightness, contrast, the higher the better, prolonged viewing of high-brightness LCD screen, the eye is also very easy to fatigue, high brightness LCD monitor will cause excessive wear and tear of the lamp, affecting life. It is also taken into account a number of reasons, weigh the pros and cons of both. Viewing angle LCD monitor is due to light through the liquid crystal to near vertical angle shot forward, and thus we have to observe when the screen from another point of view, and did not like to see the CRT monitor can be clearly seen, while will see significant color distortion. This is caused by the size of the viewing angle. Specifically, the viewing angle is divided into horizontal viewing angle and vertical viewing angle. In the choice of LCD monitors, should try to choose the viewing angle of the product. LCD monitor viewing angle substantially more than 140 degrees. 75 ° / 75 ° / 75 ° / 75 °, viewing angle (up / down / left / right): 88 ° / 88 ° / 88 ° / 88 °. In addition to the panel response time, viewing angle, color reproduction capabilities, dead pixels, highlights how much is to judge the merits of the monitor is another important criterion. Dead pixels into bright, dark spots and color spots, all refer to the physical pixel on the LCD panel can not be repaired. LCD screen is divided according to the difference between dead pixels and color purity, viewing angle and other parameters for a number of levels: AA grade: no dead pixel LCD screen as AA; A Grade: 3 dead pixels or less, of which no more than one bright spot, Highlights of the screen and not in the center of the region; Class B: 3 dead pixels or less, which highlights not more than two, and not on the screen highlights the central region; Class C: more than 3 dead pixels. Clarity of definition monitor is a monitor video channel bandwidth and CRT dot pitch and convergence errors determined for PAL signals, its channel bandwidth and clarity translated this relationship 1M78 line of the NTSC concerned, for 1M56 line; in addition, to ensure that the appropriate definition monitors, CRT monitor uses the pitch and convergence errors must also meet the corresponding requirements, for example in terms of convergence error: ≤ level of horizontal resolution monitor Width (mm) / center convergence errors (mm). It must be noted that some manufacturers in the appearance of the monitor's resolution monitor nominal exaggerated behavior. In fact, for the clarity of judgment one can monitor it through the image discrimination subjective evaluation, on the other hand can also special instruments ---- Multiburst image with an image signal generator displays the results come out discrimination. 5 Maintenance first monitor to avoid a collision with some hard object or friction. Monitor product is fragile because it's anti- "strike" capability is very small, many crystals and sensitive electrical components can be damaged when subjected to impact, and therefore usually have to be careful not to let the monitors have access to those It is easy to damage the object. Also you usually have to pay attention when cleaning the screen, do not spray cleaner directly onto the screen, because these liquids are likely to flow to the screen causing a short circuit and affect use. And should the cleaner sprayed on a soft clean cloth, then wipe the screen will be very good to avoid danger. Secondly, if you accidentally spray cleaner onto the screen, liquid detergent is injected into the screen which you do not have to worry too much. If it is found just in front of the boot screen mist the surface with a soft cloth and gently rub on it, if water has entered the LCD monitor, then the temperature is slightly higher than the LCD monitor on the place, such as table lamps will gradually evaporate the water inside. But if in case the screen "pan boom" more serious, users still call professional maintenance staff for their help request more appropriate. Because more serious moisture will cause damage to components of the liquid crystal electrode corrosion caused permanent damage. So do not let the liquid while avoiding or water into which the monitor screen, but also to try to monitor the product in a dry and ventilated environment in which to use, to avoid unnecessary trouble. Third, it is best not to use a screen saver. Why is that? Then look down you will know. Since the core structure of the LCD monitor and the "sandwich" Similarly, it is intermediate between two glass substrates is filled with liquid crystal molecules movement, signal voltage directly controls the switching state of a thin film transistor, and then a transistor control of liquid crystal molecules, liquid crystal molecules having optical obviously anisotropy, can modulate the light emitted from the backlight lamp to achieve the image appears. And a full display screen by the number of pixels constituting each pixel can switch like a transistor. A liquid crystal monitor is displaying an image, the liquid crystal molecules has been a switch in working condition, a response time of 20ms for a monitor is concerned, the work of a second liquid crystal molecule which has a switch several hundred times , while the switching times of liquid crystal molecules is, its service life is limited. After using a certain program, there will be aging, affect the results. The computer stops operating Shihai displayed on the screen so that the screen saver makes colorful repeated movement of liquid crystal molecules are still in repeatedly switching state, which will undoubtedly shorten the life of the monitor.