How to choose LED wall according to pixel pitch

Pixel pitch is one of the important technical parameters indicators of LED wall screen, what is pixel pitch? How to choose LED wall according to pixel pitch? This is what many friends doubt, the following is the engineer's best answer:
What is pixel pitch?
Pixel pitch is to reflect the pixel density from the two pixel distance, pixel pitch and pixel density is led screen’s physical attribute; Information capacity is the unit of quantity for per unit area pixel pitch’s one-off shows information carrying capacity. The smaller the pixel pitch, the higher the pixel density, the more information capacity for unit area one-off shows, the closer the viewing distance.
How to choose LED wall pixel pitch?
Choose the LED wall pixel pitch, there are two factors:
1. LED wall viewing distance.
Where is the LED wall, and usually how far the people stay to watch it, this is only one important factor for make sure pixel pitch.
Usually there is a formula for the optimal viewing distance= pixel pitch/(0.3~0.8)，this is a roughly range. For example, the pixel pitch 16mm LED wall, the best viewing distance is 20~54 meters, the closer distance, then could distinguish the LED wall’s every pixel pitch, when stay more far, then could not distinguish instead. (what we said is based on normal vision, not including the myopia and hyperopia)
For outdoor LED wall, the close distance, usually use P10 or P12，the more far distance use P16 or P20,for indoor LED wall, usually use P4~P6 is ok the more far distance use P7.62 or P10.
2. LED wall pixel pitch.
For video, the basic format is VCD, 352*288 resolution, DVD format 768*576. So for the video screen, we suggest that the lowest resolution no less than 352*288, so the display effect is good enough. If lower resolution, it also can show, but not up to much better effect.
For single and double color LED wall which mainly show text and images, not require high resolution, according to the actual size, could show the minimum 9 size font, it is up to your text amount.
Therefore, generally choose LED wall, the smaller the pixel pitch, the higher the resolution will be, and the show effect will be clearer. But this also consider the cost and demand, application scope and other factors.