As awing as our LED signs may look, it is actually pretty simple. Inside the sign cabinet you will find a receiver card along with power supplies and the LED modules.
There are two types of Light Emitting Diodes (LED) commonly used in displays. The older technology is refered to as DIP or Dual Inline Package while the newer technology is SMD or Surface-Mount Device.
DIP (top) SMD (bottom)
DIP technology delivers about 4 lumens per watt vs SMD, which delivers 50 to 100 lumens per watt making it much more efficient.
Pitch as indicated by the "P" number indicates the distance between each of the LED's in mm.The smaller the P number, the better the resolution.The technolgy is rapidly evolving. Just a few years ago P16 to P 24 signs were the standard for outdoor displays. Today P8 to P10 is the standard for outdoors and resolutions as high as P2 are being utilized for indoor displays