For people with normal vision, the naked eye can distinguish objects of 2.5 cm in size at a distance of 90 meters,
can distinguish objects of 5 cm in size at a distance of 180 meters, and objects of 10 cm in size at a distance of 360 meters.
By analogy, this is what professionals call the resolution accuracy of the human eye, which is usually 1 arc minute.
If the target is smaller than 1 arc minute for the observer, the human eye cannot recognize it.
Tests by the US special forces show that at a distance of 460 meters, it is difficult for the naked eye to distinguish a target of 12 cm in size.
But using a telescope with a 20x distance, objects of about 0.5 cm in size can generally be distinguished.
Under a certain detection distance, the minimum distance that the human eye can distinguish is used as a measurement standard.
The size of the digital camouflage unit is less than or equal to the minimum distance that the human eye can distinguish.
Only in this way, when the observer observes the digital camouflage at a detection distance closer than the previous detection distance,
can the best color mixing effect be achieved.