What are Night Vision Glasses?
Night vision glasses usually refer to any number of glasses, binoculars, goggles, or telescopes that use special means to increase vision at night. Some night vision glasses use thermal vision, some use an image intensifier, and some use active infrared. Night vision glasses can range in cost from simple consumer products that cost less than $100 US Dollars (USD), to high-end goggles that can cost many thousands of dollars. There are two main categories of night vision glasses: active and passive systems. Active systems use a device to bathe an area in non-visible light, usually in the infrared range of between 700nm-1000nm, and then have a special camera meant to see that range of light. Active night vision glasses are used by consumers and for basic security such as CCTV cameras and local law-enforcement, but aren’t particularly useful for military applications, since the light being let out can be viewed by an enemy wearing night vision glasses as well. Passive night vision glasses
