Night vision device

A night vision device, also known as NVD, is an optical instrument that allows images to be produced in levels of light approaching total darkness. They are most often used by the military and law enforcement agencies, but are available to civilian users.
==Operation==
Night vision can work in two very different ways, depending on the technology used.
*Image enhancement – This works by collecting the tiny amounts of light, including the lower portion of the infra-red light spectrum, that are present but may be imperceptible to our eyes, and amplifying it to the point that we can easily observe the image.
*Thermal imaging – This technology operates by capturing the upper portion of the infra-red light spectrum, which is emitted as heat by objects instead of simply reflected as light. Hotter objects, such as warm bodies, emit more of this light than cooler objects like trees or buildings.
==In the Halo universe==
The SRS99 series are equipped with night vision scopes. These features are only accessible to players in Halo: Combat Evolved and Halo: Reach.
The MJOLNIR Mark V is equipped with a night vision built into its systems. The Sangheili eye coverings (that give the Sangheili their HUD) are also equipped with night vision, though with a purplish-blue lighting.Halo: Reach, campaign level Winter Contingency (Carter-A259: "Can't see a thing. Noble Six, turn on your night vision.")
==Trivia==
*In Halo, night vision still has its modern day green lighting.
*Elites in Halo: Reach also have access to night vision, with a purple-blue hue instead of the regular green lighting. It is used in Firefight Versus when playing as an Elite.
*In Halo: Reach, because it outlines objects like weapons, or live objects, like Grunts, it can be used as a makeshift "visual radar," which makes it useful for finding weapons in the dark or under shallow water.
==Sources==
Category:Technology