Night vision is a spy or action movie you've seen, in which someone straps on a pair of night-vision goggles to find someone else in a dark building on a moonless night. With the proper night-vision equipment, you can see a person standing over 200 yards (183 m) away on a moonless, cloudy night.
Description of Night Vision Technology
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 infrared 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 infrared 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.
To study about night vision technology we should first know about ligt. The amount of energy in a light wave is related to its wavelength: Shorter wavelengths have higher energy. Of visible light, violet has the most energy, and red has the least. Just next to the visible light spectrum is the infrared spectrum.
Night vision technology consists of two major types: light amplification (or intensification) and thermal (infrared). Most consumer night vision products are light amplifying devices. All ITT Night Vision products use light-amplifying technology.