Infrared vision (also called thermal vision) describes the ability to detect radiation (heat) in the infrared range of the electromagnetic spectrum, producing images of that radiation.
Infrared vision grants the user the ability to detect heat signatures from anything that emits a higher temperature than the environment, and is not affected by things in the environment that may obstruct to blind the naked eye, such as fog or even thin material. Indeed, it is possible for infrared vision to detect heat signatures through thin objects such as doors or curtains/cloth material.
With the advent of stealth technologies, base defenses lost their ability to detect hidden units, forcing militaries to deploy specialized detector units, Russian commanders can opt to equip their Conscripts and VDV gunners with infrared goggles that allows them to detect hidden enemies. Unlike most detectors, however, the detection ability persists even when they are transported or garrisoned, thus even a single Conscript or VDV gunner can grant stealth detection ability for transport units and garrisonable buildings.