You cam see an example in http://arabic.cnn.com/2002/world/10/19/specialforces.jordan/
Night sight?
Night vision monocular. “Night sight” would be an aiming device attached to a weapon.
If you could see his weapon more clearly you would probably see an infrared laser pointer. The beam is invisible to the human eye, but shows up as a bright green dot in the monocular at the point of aim of the weapon.