Not to be confused with the thermal goggles(though they share an identical icon), the night-vision flavor of goggles amplifies extremely dim available light and presents it in a green-ish display so you can see what's going on in the dark. The equipment/usage method is the same as above, but the practical application of them is quite different. In situations where one must move around a lot, especially indoors with lots of obstacles, night-vision is usually the best way to go. Or if you need to work at long range outside, the thermal goggles are generally better. In the end, it boils down to personally taste/style, be it yours or whoever gives you a mission with is own equipment.