Night Vision Equipment: Binoculars, Goggles and Cameras

How Do Night Vision Equipment Work?

Night vision equipment refers to electronic-cum-optical devices which work by amplifying or intensifying whatever light there is in existence rather than depending on a source of light in-built into them. They are sensitive to a wide spectrum of light, which ranges from visible to infrared. The light that is available at the infrared part of the spectrum can be increased by an accessory illuminator, which casts a light beam that is invisible to the human eye.

Hence when viewing something with a night vision device, you do not look through it. Instead, you are viewing an electronic image that is amplified on a phosphor screen. The light enters via an objective lens and then falls upon a photo cathode, which has a high energy charge via the power supply. This charge of energy accelerates through a vacuum that exists in the intensifier and falls upon a phosphor screen, similar to a TV screen, which is the place where the image is focused. The image is magnified by the eyepiece.

The phosphor screen of a night vision device is green in color since the human eye has the ability of differentiating more green shades compared to other phosphor colors.

Similar to cameras, night vision gadgets have a variety of image magnifications. The length at which a figure about the size of an adult human can be discerned clearly under normal night lighting conditions, such as star light and moon light, without any fog or haze, is dependent on both the strength of the image intensifier as well as the power of the objective lens.

Night Vision Equipment Technology

There are two ways by which night vision can work, according to the technology used.

Thermal Imaging Technology: In this night vision technology, the upper part of the spectrum of infrared light is captured. This is given off as heat by objects rather than being reflected as light. Warmer bodies, such as humans and animals, give off more of this light compared to colder objects such as buildings or trees.

Image Enhancement Technology: In this night vision technology miniscule amounts of light are collected, which includes the lower part of the infrared light spectrum, which are in existence but may not be perceptible to human eyes, which is them amplified to the extent that the image is easily visible to us.

Night Vision Equipment

Here are some of the commonly used night vision equipment:

Night Vision Binoculars or Goggles: While these are usually worn on the head, they can also be handheld. They have two eye pieces and can either be equipped with a stereo lens or a single lens, according to the model. These night vision gadgets are ideal for having a constant view of the object, and also while walking around in a darkened building. These are very useful for night surveillance that is done covertly, home surveillance, home security, viewing animals or hunting them after dusk, keeping watch at night, stargazing, and watching comets and shooting stars.

Night Vision Scopes: Usually handheld or attached to a weapon, these are monocular devices, or single eye pieces. Since the user does not wear them like goggles, they are ideal for getting a better look at a particular object and then returning to normal viewing.

Night Vision Cameras: Cameras that are equipped with night vision technology have the ability of sending images to a monitor where they are displayed. These night vision cameras are used where permanent surveillance is required, like on a building or when it forms a part of the equipment as in a helicopter. Many of the new camcorders that are coming in the market come with in-built night vision.

Digital Night Vision Equipment: These can be used in the night as well as the day time without the sensitive imaging tubes being harmed. There are digital night vision binoculars, monoculars, goggles, scopes, and so on.

Applications of Night Vision Equipment

Night vision technology was originally created in order to find enemy targets after dark. The military still uses it extensively for targeting, surveillance, and navigation. The police too use it for surveillance, as do nature enthusiasts and hunters. Many businesses install night vision equipped cameras for monitoring purposes. Private investigators and detectives too find these gadgets useful in the line of their work.