How to choose outdoor LED display?

LED display purchasing knowledge points

What are the brightness requirements for the screen body based on ambient brightness?

General brightness requirements are as follows:

(1) Indoor: >800CD/M2

(2) Semi-indoor: >2000CD/M2

< p>(3) Outdoor (sit from south to north): >4000CD/M2

(4) Outdoor (sit from north to south): >8000CD/M2

Consider what the user site allows What are the factors that determine the screen area?

(1) The relationship between effective viewing distance and actual site size;

(2) Pixel size and resolution;

(3) The unit is the base number Area estimation;

(4) Screen mechanical installation and maintenance operation space;

(5) Effect of screen inclination on distance.

What playback effects do users need?

(1) Text display: Depends on the 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;

Red, green and blue in white composition What are the brightness requirements?

Red, green and blue contribute differently to the color of white. The fundamental reason is that the retina of the human eye has different perceptions of light of different wavelengths. After a large number of experimental tests, the following approximate ratios are obtained for reference design:

The simple red, green and blue brightness ratio is: 3:6:1

The precise red, green and blue brightness ratio is: 3.0 :5.9:1.1

Why do high-end full-color displays use pure green tubes?

In the actual production of LED display screens, LED lamps should be selected that have high luminous efficiency and can obtain rich and bright colors

so as to achieve the desired results in the chromaticity diagram. The area of ??the color triangle should be as close as possible to the tongue-shaped spectrum color curve to meet the rich colors and emit sufficient brightness. The tip of the tongue-shaped curve is 515nm wavelength light, so high-end LED displays use pure green light LED tubes with wavelengths close to 515nm. , for example, choose LED lamps with 520nm, 525nm or 530nm wavelength light.

How to calculate the brightness of a single tube under the clear requirements of brightness and dot density?

The calculation method is as follows: (Take two red, one green, and one blue as an example)

Red LED light brightness: brightness (CD)/M2÷points/M2×0.3÷2

Green LED light brightness: brightness (CD)/M2÷points/M2×0.6

Blue LED light brightness: brightness (CD)/M2÷points/M2×0.1< /p>

For example: 2500 points per square meter density, 2R1G1B, brightness requirement per square meter is 5000 CD/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

Per pixel The brightness of the dot is: 0.3×2+1.2+0.2=2.0 CD

Why use the DVI display interface standard?

(1) The DVI display card interface is a display interface that complies with international computer standards;

(2) It can be easily installed without opening the chassis;

( 3) High video memory and strong dynamic screen display capability;

(4) Strong software and hardware compatibility;

(5) Supports all operating systems and application software, with flexible and convenient display;< /p>

(6) Mass production, low cost and easy maintenance.

Can the display screen be controlled by a laptop? Why?

No.

The graphics card of the notebook computer is built-in and cannot be connected to the control system. Currently, BOE has a notebook with a DVI interface that can realize notebook control.

Except for price, what are the differences between using Nichia tubes for full-color screens and using domestic tubes?

(1) Tube core: Nichia Company produces tube cores independently, and domestic tubes generally use tube cores from American or Taiwanese companies;

(2) Packaging: Nichia Company independently packages them , there are no production factories in China, and there are many domestic tube packaging manufacturers;

(3) Consistency: Nichia tubes in the same batch have a small wavelength difference in tube cores and good consistency, while domestic tubes have relatively poor consistency;

(4) Service life: Nichia tubes have a relatively long service life, while domestic tubes attenuate more seriously;

What is the difference between indoor module full-color screens and SMD full-color screens?

(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 tube core;

(2) Display effect: The module full-color screen has thicker pixels, lower brightness, and is prone to mosaics; the patch full-color screen has better consistency and higher brightness;

(3) Maintenance : Full-color modules are difficult to maintain, and the replacement cost of the entire module is high; full-color SMD modules are easy to maintain, and single lamps can be repaired and replaced;

Why is the production cycle of outdoor screens relatively long?

(1) Raw material procurement: The procurement cycle of LED lamps is long, especially imported tube cores, the ordering cycle takes 4-6 weeks;

(2) The production process is complex: it requires PCB design, cover production, glue filling, white balance adjustment, etc.;

(3) Strict structural requirements: Generally, it is a box design, and windproof, rainproof, lightning protection, etc. need to be considered.

How to help users choose a suitable display screen?

(1) The need to display content;

(2) Confirmation of viewing distance and viewing angle;

(3) Requirements for screen resolution;

(4) Installation environment requirements;

(5) Cost control;

What is the general aspect ratio of a display screen?

Graphic screen: determined according to the displayed content;

Video screen: generally 4:3 or close to 4:3; the ideal ratio is 16:9.

How many points can a control system control?

Communication screen A card: single color, dual color 1024×64

Communication screen B card: single color: 896×512 dual color: 896×256

DVI Dual-color screen: 1280×768

DVI full-color screen: 1024×512

What factors are generally considered in the size design of the display screen?

-When designing the screen size, there are three important factors:

(1) The need to display content;

(2) Site space conditions;

(3) Display unit template size (indoor screen) or pixel size (outdoor screen).

-Displays above 10 kilowatts should be equipped with step-down starting equipment.

-Communication requirements: The communication distance is defined by the length of the communication line.

-The communication cable must be installed according to the communication cable length standard for the model of the display screen being installed.

-Communication lines are prohibited from being routed in the same conduit as power lines.

-Installation requirements: The left and right sides of the display screen are installed horizontally, and backward tilting is not allowed

-Up and down adjustment rods must be installed for hoisting installations

-The front panel must be installed before wall-mounting installation. Tilting hook

- Positioning support bolts are required for floor installation.

What are the display power consumption indicators and power requirements?

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 in normal times. The maximum power consumption is the power consumption during extreme conditions such as startup or full brightness. The maximum power consumption is a factor 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 precision electronic device. For safe use and reliable operation, its AC220V power input end or the AC220V power input end of the computer connected to it must be grounded.

Note: The AC220V power input ground terminal of the computer has been connected to the computer case.

What are the installation requirements for the display screen?

Power supply requirements: The power supply connection point should be within the size of the screen

220V mains power supply, live wire 0 wire ground wire;

380V mains power supply, Three live wires and one 0-wire ground wire;

The cross-sectional areas of the live wire and 0-wire wires are the same;

Displays above 10 kilowatts should be equipped with step-down starting equipment.

Communication requirements: Communication distance is defined based on the length of the communication line.

The communication cable must be installed according to the communication cable length standard for the model of the display screen being installed.

Communication lines are prohibited from being routed in the same conduit as power lines.

Installation requirements: The left and right sides of the display screen should be installed horizontally, and backward tilting is not allowed

Up and down adjustment rods must be installed for hoisting

Forward tilting hooks must be installed before wall-mounting installation.

Add positioning support bolts for floor installation.

What issues should be considered in the design and installation of outdoor screens?

The main problems of outdoor screens are as follows:

(1) The display screen is installed outdoors, often exposed to the sun and rain, wind and dust cover, and the working environment is harsh. Electronic equipment that is wet or severely damp can cause short circuits or even fires, causing malfunctions or even fires, causing losses;

(2) The display screen may be attacked by strong electricity and magnetism caused by lightning;

(3) The ambient temperature changes greatly. The display itself generates a certain amount of heat when it is working. If the ambient temperature is too high and the heat dissipation is poor, the integrated circuit may not work properly or even be burned, so that the display system cannot work normally;

(4 ) The audience is wide, the viewing distance is required to be long, and the field of view is required to be wide; the ambient light changes greatly, especially it may be exposed to direct sunlight.

In view of the above special requirements, outdoor display screens must meet the following requirements:

(1) The screen body and the joint between the screen body and the building must be strictly waterproof and leak-proof; the screen body must be in good quality Drainage measures should be taken so that water can be discharged smoothly once water accumulation occurs;

(2) Install lightning protection devices on display screens and buildings. The main body and shell of the display screen should be well grounded, and the ground resistance should be less than 3 ohms, so that large currents caused by lightning can be discharged in time;

(3) Install ventilation equipment to cool down so that the internal temperature of the screen body is between -10℃~ between 40℃. An axial flow fan is installed above the back of the screen to dissipate heat;

(4) Use industrial-grade integrated circuit chips with operating temperatures between -40°C and 80°C to prevent the display from failing due to low temperatures in winter. start up. ;

(5) In order to ensure long-distance visibility under strong ambient light, ultra-high brightness light-emitting diodes must be used;

(6) The display medium uses new wide-angle tubes , wide viewing angle, pure colors, consistent and coordinated, and a lifespan of more than 100,000 hours. The outer packaging of the display medium is the most popular square cylinder with a shielded edge, silicone seal, and no metal assembly; its appearance is exquisite and beautiful, sturdy and durable, and has the characteristics of protection against direct sunlight, dust, water, high temperature, and circuit short circuit "Five defenses" features.

Our company specializes in the production of LED fully automatic glue filling machines; LED module glue filling machines; LED fully automatic flexible light strip glue filling machines, LED light strip placement machines and light strip processing. Welcome to call us. Write to discuss! Chen Sheng (my 163 blog: LED Bolin)