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LED lamp as highest cost and maximum components for LED display, it has the main influence for LED display's quality. Here, let us introduce how to recognize the quality of this key point - LED lamp of the LED screen.

Why LED full colour screen's most key point are LED lamps, 3 reasons as below:

1. Maximum components of LED display, thousands LED lamp per squre meters;
2. The subject of display perfomance, influence the judgement of the audience directly;
3. It takes highest cost in the whole LED screen's part, from 30%~70%.

How to recoganize LED lamp good or bad:

1. The soldering point: Regular LED strip producer are using SMT technology: tin,resodering skill to produce.
2. FPC quality: FPC including points apply copper and RA copper.
3. Clean rates on the surface of LED strip, SMT technology can bring very clean and no impurity and besmirch.
4. LED chip has less attenuation will be better.

The influences of LED lamp to LED screen

• Viewing angle: Most of outdoor DIP LED lamp are using 110°(Horizontal)/55°(Vertical) of the oval shape. Indoor SMD LED lamp are using 120°(Horizontal/Vertical). Viewing angle and brightness has opposite way. Higher brightness, lower viewing angle.
• Brightness: LED higher brightness with more currency and less wastage, more stable for LED screen. Chip brightness are the same, smaller viewing angle, more brighter. We should always find a balance in different pixel pitch and different viewing distance LED display when purchasing.

• Failure rate: LED screen is made up by thousands of R, G, B pixel pitch, any colour LED failed will influence whole visual. As LED screen industrial standard, LED failure rate less than 0.03%.
• Anti-static: LED belongs to semiconductor, it is very easy to be failed because of static. So, anti-static is very important for LED screen, LED's human static mode test failure voltage should over 2000V
• Lifespan: LED device theory lifespan: 100,000h, it is much longer than other components working lifespan of LED screen. So, LED device's quality accured, working currency is resonable, PCB board has resonable heat dissipation, strict producing technology. LED device will be the most durable parts
• Attenuation phenomenon: LED screen will be turning into lower brightness and different color after long time use, this all because of the attenuation phenomenon. If R, G, B has different attenuation, screen will show different color. Therefore, basic on 1000h normal temperature and 20mA as standard. Red attenuation <2%; G,B<10%. So, G, B lamp should use rated current 70%-80%, do not use 20mA current.   Attenuation phenomenon is not only about R,G,B lamp, PCB board heat dissipation, current, working temperature all lead to it.
• Size of LED lamp: It is influence the resolution of LED screen. 5mm oval LED lamp always use in outdoor about 16mm pixel pitch(Already out of market).  3mm oval LED lamp are using in 10mm, 16mm outdoor LED screen (Most popular DIP LED lamp for outdoor use). Indoor use: SMD3528 and SMD2020, number smaller, LED lamp size smaller.
• Consistency: LED screen is made by thousands of R, G, B lamps. Each LED's brightness and wavelength decide the consistency of white balance, brightness and color. Manufacturer requires 5nm wavelength and brightness range in 1:1.3.

LED has viewing angle, different viewing angle will get different brightness, therefore, higher level LED package company will get higher quality LED screen.