Ten factors to consider when purchasing an LED display
When purchasing LED displays, many customers do not know how to buy cost-effective products, and many users search for information on the Internet, but they always get no satisfactory answers. So what are the factors that should be considered when purchasing a display screen?
1. What is the aspect ratio of the general display screen?
(1) Graphic screen: determined according to the displayed content;
(2) Video screen: generally 4:3 or close to 4:3; the ideal ratio is 16:9.
2. What factors are generally considered in the size design of the display screen?
(1) The need to display content;
(2) Site space conditions;
(3) Display unit template size (indoor screen) or pixel size (outdoor screen).
3. Need to know the number of points that the control system can control?
Communication screen A card: single color, double color 1024×64
Communication screen B card: single color: 896×512 double color: 896×256
DVI dual color screen: 1280×768
DVI full color screen: 1024×512
4. What are the power consumption indicators and power requirements of the display screen?
The power consumption of the display screen is divided into average power consumption and maximum power consumption. Average power consumption, also known as working power, is the actual power consumption at ordinary times. The maximum power consumption is the power consumption in extreme situations such as startup or full brightness, and the maximum power consumption is an element that must be considered for AC power supply (wire diameter, switch, etc.). The average power consumption is generally 1/3 of the maximum power consumption. The display screen is a large-scale precision electronic equipment. In order to use it safely and work reliably, its AC220V power input terminal or the AC220V power input terminal of the computer connected to it must be grounded.
5. What are the differences between indoor module full-color screen and SMD full-color screen?
(1) Light-emitting part: The display module of the module full-color screen is generally yellow-green, and the pure green module is more expensive; the SMD full-color screen generally uses a pure green die;
(2) Display effect: The pixel point of the module full-color screen has a thick visual perception, low brightness, and is prone to mosaic phenomenon; the patch full-color screen has good consistency and high brightness;
(3) Maintenance: The full-color module is not easy to maintain, and the replacement cost of the entire module is high; while the full-color patch is easy to maintain, and can be repaired and replaced for a single lamp;
6. Why is the production cycle of outdoor screens relatively long?
(1) Procurement of raw materials: The procurement cycle of LED lamps is long, especially for imported tube cores, and the order cycle takes 4-6 weeks;
(2) The production process is complex: it needs to go through PCB design, cover production, glue filling, white balance adjustment, etc.;
(3) Strict structural requirements: it is generally designed for the box body, and it is necessary to consider windproof, rainproof, lightning protection, etc.
7. What are the factors that need to be considered in the allowable screen area of the site?
(1) The relationship between the effective sight distance and the actual site size;
(2) Pixel size and resolution;
(3) Area estimation with unit as base;
(4) Operating space for mechanical installation and maintenance of the screen;
(5) The influence of the inclination of the screen on the distance;
8. What are the brightness requirements of the ambient brightness for the screen?
The general brightness requirements are as follows:
(1) Indoor: >800CD/M2
(2) Semi-indoor: >2000CD/M2
(3) Outdoor (sitting south to north): >4000CD/M2
(4) Outdoor (sitting north and facing south): >8000CD/M2
How to calculate the brightness of LED lights under the requirements of clear brightness and dot density?
The calculation method is as follows: (Take two red, one green, and one blue as an example)
Brightness of red LED light: Brightness (CD)/M2÷Points/M2×0.3÷2
Green LED light brightness: Brightness (CD)/M2÷Points/M2×0.6
Brightness of blue LED light: Brightness (CD)/M2÷Points/M2×0.1
For example: the density of 2500 dots per square meter, 2R1G1B, the brightness requirement per square meter is 5000CD/M2, then:
The brightness of the red LED light is: 5000÷2500×0.3÷2=0.3
The brightness of the green LED light is: 5000÷2500×0.6=1.2
The brightness of the blue LED light is: 5000÷2500×0.1=0.2
The brightness of each pixel is: 0.3×2+1.2+0.2=2.0CD
9. What are the effects of playback that need to be considered?
(1) Text display: It depends on its text size and resolution requirements;
(2) Ordinary video display: 320×240 dot matrix;
(3) Digital standard DVD display: ≥640×480 dot matrix;
(4) Complete computer video: ≥800×600 dot matrix;
10. Need to know about the design and installation of outdoor displays?
(1) The junction of the screen body and the building must be strictly waterproof and leak-proof; the screen body must have good drainage measures, so that the water can be discharged smoothly once it occurs;
(2) Install lightning protection devices on display screens and buildings. The main body and shell of the display screen are well grounded, and the grounding resistance is less than 3 ohms, so that the large current caused by lightning can be discharged in time;
(3) Install ventilation equipment to cool down, so that the internal temperature of the screen is between -10°C and 40°C. An axial flow fan is installed above the back of the screen to discharge heat;
(4) Select industrial-grade integrated circuit chips with a working temperature between -40°C and 80°C to prevent the display from being unable to start due to the low temperature in winter. ;
(5) In order to ensure long-distance visibility in the case of strong ambient light, ultra-high brightness light-emitting diodes must be selected;
(6) The display medium adopts a new type of wide viewing angle tube, which has a wide viewing angle, pure color, consistent coordination, and a life span of more than 100,000 hours. The outer packaging of the display medium is currently the most popular square cylinder with a shielded edge, which is sealed with silicone and has no metallized assembly; its appearance is exquisite and beautiful, sturdy and durable, and has the functions of preventing direct sunlight, dust, water, high temperature and short circuit. “Five defenses” features.