Dual In-Line Package (DIP)
DIP LEDs contain two connecting pins which are mounted through-hole to PCBs (printed circuit boards). DIP LEDs have higher optical decay, lower CRI, and lower efficiency than the more recent SMD LEDs. However, many DIPs are used in larger pixel pitch outdoor LED screens to achieve higher brightness.
Surface Mounted Device LED
SMD LEDs are the more recent, resilient, efficient, and long-lasting technology for mass production. SMD parts can be made smaller and thinner because the part is only soldered to the “surface” of one side of the circuit board. SMD screens usually use 3-in-1 LEDs. With one RGB 3-in1 LED unit per pixel, there are three tiny LED chips sealed inside a single part. Therefore, the color blends better, and the image is sharper.
COB(Chip On Board ) Technology
Newer COB technology presents many advantages: wide viewing angle, solid dustproof, shockproof, and often waterproof surface which is rigid and prevents damage to LED elements. Flat and even face minimizes moire effect. There are a few manufacturers who are experimenting with this upcoming technology and some products are already available for purchase. Unfortunately, there are also challenges associated with COB LED video screens that are yet to be resolved.
Black SMDs are the same as White SMDs but with a tanned front to mask reflective surface, which results in a darker screen, thus, deeper black levels and a much higher contrast ratio. Typically black SMDs are more expensive and less bright but very effective in concerts and outdoor applications, especially under direct sunlight.