Page 1: LCD panel is very important
In the article the day before yesterday, we summarized the many performance differences between the TV and the monitor. Through these comparisons, we can find that if the TV is used instead of the monitor, it will obviously not work. Therefore, if you want to complete high-quality video surveillance, it is obviously "not running" to choose a high-quality qualified video monitor. So how do we polish our eyes and choose from? So that you don't let your expected monitor fall to "TV level"? Below, the editor has summed up the focus of some video monitors to protect our system quality.
LCD panel is important
In security monitors, the LCD panel largely determines the brightness, contrast, clarity, etc. of the monitor. Therefore, its output, advantages and disadvantages, and market environment will affect the quality of the product. Therefore, when we choose a monitor, the editor recommends that you better choose a more well-known brand, so that both in terms of technical maturity and mastery of quality itself, we have a more comprehensive understanding. It is also very helpful for quality assurance.
Nowadays, LCD panels can be divided into three grades of ABC according to quality. Although there are no hard and fast rules, under normal circumstances, the number of panel defects is within one of the A grade, and more than three are the C grade, only Very few manufacturers who dare to make a promise of no dead pixels will claim to be A + products. Therefore, when shopping, consumers must personally check the picture quality of products, especially those that claim to be A +, to avoid being deceived by illegal vendors. Go for more money.
Page 2: Display scale selection
Display scale selection
Currently, like TVs, monitors have many screen ratios. The common screen sizes on the market today include 17-inch, 19-inch, 20-inch, 32-inch, 42-inch and larger screen areas. The horizontal and vertical ratio of the screen is also divided into 16: 9, 4: 3, or 5: 4. Perhaps in the eyes of some users, this may just be a choice of size or monitoring habits. Actually it is not. Like the monitor device, the front-end surveillance camera also has a fixed aspect ratio during operation. If the aspect ratio of the front and rear ends is difficult to match, the displayed image will be distorted or deformed, which will have a certain impact on the monitoring effect.
Monitor motherboard (picture source network)
At present, although there are many kinds of aspect ratios of monitors, from the application point of view, the ratio of 16: 9 is currently the ratio approved by most surveillance cameras. High-definition network cameras similar to 720p * 1080i basically accept the 16: 9 format. In the long run, 16: 9 is likely to become the mainstream ratio of surveillance cameras in the future. When we choose equipment, the 16: 9 ratio should be worthy of everyone's special attention.
Investigation of imaging performance
When we introduced how to buy a surveillance camera, we often advise consumers to make a decision based on actual conditions after actual comparison. The same is true for monitors. However, the comparison is easy, but in the process of actual operation and observation, what aspects should be paid attention to?
Page 3: Reference factors for imaging parameters
Resolution
For the choice of resolution, we also use the 16: 9 screen ratio as an example. Currently, the physical resolution of this widescreen design is 1368 * 768. For this parameter, we can use the signal generator to input the clarity test signal, and then observe the number of related lines displayed, so as to observe whether it meets the requirements of this level of quality. In addition, we can also set a high-speed moving object to pass in front of the monitoring lens during monitoring, so that we can see the reaction rate of the monitor, and whether there is a phenomenon of tailing and so on.
Reaction time
Speaking of the corresponding time, we can take a look at the current level of a corresponding time. Currently, response time has become an important selling point for monitor manufacturers. In the camera work project, if you want to achieve the best monitoring effect, it is difficult to achieve without a response speed of 60 frames per second. And such a rate can only be satisfied by the reaction speed within 16ms.
Monitor wall (picture source network)
But you do n’t have to worry that the response time of the current mainstream monitors has basically reached the level of 8ms, which can meet the processing intensity of 125 frames per second. However, for users who are not in high demand, 12ms or 16ms products are actually sufficient. Especially for some conventional fixed-point low-speed dome cameras, 8ms is somewhat wasteful.
Brightness and contrast selection
When we choose a monitor, we often see a choice of brightness and contrast. And what kind of response are these two parameters? Generally speaking, the higher the brightness of the LCD monitor, the more vivid its colors, and the better the actual display effect. And for those products with lower brightness. The image it displays will also be darker, thereby increasing user fatigue. At present, the brightness of an ordinary monitor is around 250 cd /, and too bright and too dark will affect the imaging.
Page 4: Monitor stability investigation
After speaking of brightness, we must talk about contrast. After all, the value of contrast is derived from the brightness of white screen divided by the brightness of black screen. Therefore, the greater the gap between the two, the clearer the displayed picture, and the stronger the sense. In general, the contrast ratio of the LCD monitor is around 3000: 1, and the contrast ratio of the traditional CRT monitor will be much lower than that of the LCD screen. However, for monitors, 400: 1 has almost reached the contrast of the monitor. When the contrast is lower than 300: 1, this monitor can be ignored.
Observation of viewing angle
In terms of viewing angle, this is a new reference direction in the field of monitors. Since the light of the LCD monitor is emitted vertically through the liquid crystal at a nearly vertical angle, the color of the screen will change greatly when the screen is viewed at different angles. This problem will not be encountered in traditional CRT monitors.
Large-screen LCD monitor (picture source network)
In observation, the viewing angle can be divided into horizontal angle and vertical angle. When choosing a monitor, a larger monitoring angle is undoubtedly the best choice. Although the current viewing angle may be different under many brands, it is absolutely the same as the evaluation standard of monitoring.
Monitor stability
Actually when it comes to stability, I am afraid that everyone will feel that it should be the most relevant to everyone, but it is also one of the most helpless places. If stability is "looked" out of thin air, then this is indeed a bit exaggerated. However, on the surface, there are indeed a few small areas that can more or less help to extend the service life of our equipment. Housing, good heat dissipation effect, advanced cooling fan and temperature control mode, etc. In addition, the application technology of the screen can also be the object of understanding.
The above are the main points that we pay attention to when selecting LCD monitors. In fact, according to different needs, the monitors pay much attention when purchasing. Here is just some important information for everyone. I hope everyone can buy a suitable monitoring device for themselves on the basis of understanding. Since we are a monitor, let us show it more domineering than TV, you say?
