|Как правильно выбрать светодиодный экран|
Как правильно выбрать светодиодный экран или вывеску
КАК ВЫБРАТЬ ЭКРАН
Прежде, чем Вы купите видео экран:
Размеры и местоположение видео экрана
Тип информации выводимый на видео экран
Выбор шага между пикселями
Реальное и виртуальное разрешение видео экрана
Яркость и углы обзора
Расстояние смешивания цветов, минимальное и максимальное расстояние наблюдения
Выбор системы управления светодиодным экраном
Выбор производителя или поставщика видео экрана
Выбор производителя металлоконструкции видео экрана (для наружных экранов)
How to choose the right LED display sign
This section is intended primarily to inform the potential buyer with the main criteria for selecting a video screen before the purchase and the decisions taken on the basis of these recommendations may not be 100% correct choice of unique LED screen. The specific model of the video screen is 90% determined by the place of its installation and the conditions of its review. This section will help you to speak the same language with our experts in the discussion of various models of video screens.
But we strongly recommend you the choice of a particular model or LED screen signs, invite our specialist for examination installation location, in order to assess their prospects, take photos of places for you to prepare fotomaket place with the screen.
This service is provided free of charge and we will help you make the right choice LED screen!
Before you buy a video screen:
Evaluate the size and location of your screen
Decide what type of information you plan to screen
Decide on a pixel pitch screen (screen resolution)
Decide on the real and the virtual screen resolution
Decide on the brightness and viewing angles of the screen
Determine the minimum and maximum viewing distance
How many and what types of video signals, you'll use
Will screen set in place permanently or will move to other locations
Select the screen control system
Select a video screen manufacturer
Select manufacturer metal screen
The size and location of the video screen
The process of model selection screen video (its size and resolution) - extremely important, because the correct choice of the model depends not only on the cost of the whole project, but also the prospects of the business of selling advertising time, because the wrong-chosen video screen can not improve, worsen the sale of advertising time, no matter how good the place was not setting the screen (for example, the most effective distance Review screen 400 - 600 meters, and a display 3 x 4 meters, which means that 200 - 300 meters effective angle - simply lost).
Additional guidance on the definition of the parameters and the linear dimensions of the video screen you will find in our category "Effective viewing distance."
The type of information output to the video screen
Identifying these factors in advance will allow the manufacturer / supplier to estimate the required pixel pitch LED screen and its characteristics. When you plan the budget for the purchase of video screen, and especially the LED screen, you should be aware that without considering the content of what you will be showing on the screen, the final effect can be disastrous.
This is a good rule - first determine the content of your page views:
only pre-video ads
promotional videos and live video from external video sources (TV signal, a video camera, CD / DVD player) with sound
Only live video from external video sources with audio
Choosing pixel pitch
Selection of pixel pitch and resolution of the video screen dictate the physical limitations of the video screen size, viewing distance and viewing angles, and, of course, the budget - the cost is determined by the resolution of the screen and the area!
The key to high-quality image on a video screen, large format - buy a screen with the highest resolution that you can afford. Resolution is determined by the total number of vertical and horizontal pixels (dots which form the whole image). More details about the screen resolution and pixel you can find in the "How it works".
If you plan to show live video, the video that will play the video screen, a native resolution of about 486 (NTSC) and 576 (PAL-SEKAM) vertical lines and somewhere around 240 - 720 lines of horizontal (depending on the quality of source). To reproduce these signals with no loss of image resolution, you need a minimum resolution of the video screen approximately 648 x 486 (NTSC) or 768 x 576 (PAL-SEKAM).
If you will be using for the live video screen with fewer pixels than the source signal, reproducible screen images will have a lower resolution than the source. However, if the video screen is designed properly, it can give a good video. Screens with a resolution of 1/2 resolution VGA (320 x 240 pixels) is quite acceptable for this purpose.
At the moment, the de facto screen resolution of 320 x 240 pixels. Setting the video screen with a resolution of less than 256 x 192 pixels is not recommended.
The real and the virtual resolution video screen
We advise you to pay special attention to this key moment when you choose the screen and producer respectively.
For more information on the real and virtual resolution LED screen you can find in the "virtual pixel".
The brightness and viewing angles
Unit of measure brightness LED screen - nits (cd/m2) - the higher the value, the higher the brightness of the video screen. As a rule, the brightness for indoor screens should be no more than 1500 - 2000 nits, and for outdoor screens from 3500 nits (for screens with no direct sun exposure) to 5000 nits or more (when using a screen with direct sun flare) . Brightness is measured under normal angle to the screen. The color temperature of the video screen should be used to 5000 ° K for the internal screen, and 6500 ° K for the outdoor screens.
Viewing angle is usually determined by the point where the brightness of the screen is 50% of the maximum. If you walk along the screen, you will see a change in brightness. LED screens have a problem that is unique to this technology, called the "enclosure of the shoulder" (from the English "shouldering"), when the color change is caused by the fact that one LED blocks (blocking) of the other LED on the critical angles.
Viewing angles should really include color changes, and if a significant color change occurs before the brightness drops to 50%, then this is the viewing angle. Adding peaks between pixels or rows of LED video screen reduces flare other light sources, and increases contrast. It also reduces the vertical viewing angle, but this is usually not a problem for most applications of LED screens.
For example, for roof installations screens important than a wide viewing angle, and the direction of the video screen on the priority flow of the audience, that's why the video screens with a viewing angle of 60 degrees instead of 120 degrees to allow a more efficient use of LED video screen and its brightness.
If the producers of the video screen is used to control high current LEDs, they can specify the brightness of more than 7000 nits, although for LED pixel pitch of 25 mm and above, it is physically impossible to get higher brightness 5000 nit. But the problem of the high brightness of the screen is in the fact that the high current LED drivers lead to more rapid degradation, and uniformity of brightness and color screen can change quickly. Usually, the "lifetime" of LEDs appear in the range of 20 000 to 100 000 hours.
These figures display brightness is valid unless they are defined by the actual currents drive the LEDs to be used in the real world of the show - and of course when measuring the brightness of the actual display. In assessing any video screen large format, always resolve it with the manufacturer or vendor.
Distance color mixing, the minimum and maximum viewing distance
Distance mix of colors:
When considering the pixels near the LEDs RGB (red, green, blue) are shown as independent points. The distance from the LED screen where mixing three separate colors in one color is known as "color mixing distance."
The ability to better mixing colors makes images appear clear and crisp close and is a vital factor for the internal video screens. For external screens conventional LED type "lamp", color mixing distance can be calculated by the formula: pixel pitch, multiplied by 500.
For example for a video screen pixel pitch 19mm length color mixing is 19 mm x 500 = 9.5 m
For internal screens with SMD LEDs (three LEDs in one housing), the number - 250, since the LEDs are located close to each other. Therefore, the internal LED display with pixel pitch of 10 mm distance is equal to - 2.5 m distance is sometimes mistakenly referred to as the minimum distance of observation.
Minimum viewing distance:
This value can be calculated as the pixel pitch, multiplied by 750 - 1000. At this distance, there is a smoother image. A closer look would have the effect of the "disintegration" of the image into separate points (pixels). For example, for video display pixel pitch 19 mm, this distance is equal to - 19 mm x 1000 = 19 m
The maximum viewing distance:
This is usually 20 - 30 screen heights. For example for a video screen height 4.56 meters: 30 x 4,56 m = 137 m
Selecting the control LED screen
When you select a video screen, pay special attention to the control system screen. This is usually under the control computer by Windows. But if you plan to connect your screen to the Internet for remote control of the schedule showing videos and download them to the hard disk of the master plan to connect your PC or your screen to a network of LED screens with management from a single center, it is preferable to select a control unit that operates under the operating system Unix or its clones (such as Linux), as this will improve the stability of the control system and protect it from unauthorized access and attacks.
Choice of the manufacturer or vendor video screen
Of course this is the key point to select the video screen and the focus we recommend you to pay the following:
Portfolio (quantity and quality of completed projects)
Projects implemented for large customers
Warranty, Service, and Support
Technical equipment of the company (having its own laboratory for the measurement of light-emitting diodes and modules, the availability of instrumentation for measuring the brightness of the video screens
Availability of our own development team (then it is really a manufacturer, not the vendor or reseller)
Analysis of the lineup video screens and its similarity to the lineup of Asian manufacturers
The basic aspect of the evaluation of integrity, reliability and credibility of the manufacturer or supplier - it offered a model with a physical or virtual (dynamic) resolution
LED technology has become much more accessible, which resulted in a large number of manufacturers of LED screens (one report on the industry refers to as much as 100 producers, although to date, this amount may be in China alone!). An unfortunate side effect of this diverse industrial activity - the rapid increase in the market of poorly designed products and the emergence of some short-term manufacturers who can sell only a few systems prior to his disappearance from the market.
One of the key aspects when choosing an LED screen is the choice of the manufacturer, with extensive experience and a history of producing full-color LED video screens, and who devotes himself only to this industry.
If you came to the possession of unsupported "orphan" video screen, you can not say you were not warned!
In particular, beware of the new LED screens from the company, which until then had only made animated LED signs, and has no experience in the production of video screens. Showing a "live" video on the big screen requires a very high speed processing.
Choose manufacturer metal video screen (for outdoor displays)
Do not order the metalwork from third-party manufacturers, trying to save money - this will cause you a headache and extra costs. Check with the manufacturer or supplier of the screen, whether it has its production base for the manufacture of metal or a subcontractor who already has experience in the construction of such structures.