Night vision devices help you see the surroundings in the dark. It is used to see animals, objects or people located at 800-1000 yards away at night. For things that you cannot see in the night through naked eyes, night vision cameras are useful for you to take photos or making videos.
There are two technologies used in night vision devices. Traditional devices use optoelectronic image enhancement that works by detecting small quantity of infrared light which reflects off objects. After that the device electrically amplifies that light into a shining green image. Another technology is called digital image enhancement that captures light on a sensor that enhances the digital image in a complete-color display.
Optoelectronic image enhancement
Optoelectronic image enhancement has been used in older or traditional vision devices. The technology involves a sequence of visual lenses and an electric vacuum tube for capturing and amplifying the image and IR light that reflects off close objects.
Objective lens is the first lens and captures the blurred visible light that reflects from the subject together with light from the low end of the infrared range. This light is comprised of photons. Photons pass across the lens into an image intensifier tube. This is a special tube powered through small N-cell or AA batteries that contains two components.
Photocathode is the first part of the vacuum tube. This converts the photons into electrons. Photons, electrons and neutrons are very small molecules that contain the modules of an atom. Electrons spin round the nucleus that is the combination of photon and neutron. While spinning, electron carries an electric charge.
Through the second part of the tube that is called MCP or the microchannel plate, the new electron flows. The second part is a glass disc containing millions of small holes that increases electron numbers and amplifies the electronic signal thousand times over.
When the electrons exit from the tube, they knockout a phosphor-coated screen. On the screen, the phosphor creates a shining green image that is brighter than the previous light. You can see the glowing image by an ocular lens that helps to focus and magnify your image.
Moreover, the transformation of the photons into electrons clears the color facts from image and converts them into black and white image. Green phosphors on the screen is selected because it is the easier color to see in the dark.
Digital image enhancement
Nowadays most of the night vision gadgets use digital image enhancement in their technology that results in light-weight, more versatile and smaller night vision tools. Here, the light changed into a digital signal through a metal-oxide-semiconductor sensor and enters into the objective lens. The image is enhanced electrically and being magnified many times, directed to the LCD display for looking. The resolution of your image depends on the size of the sensor. Large sensor can give you high resolution image.
To view through the LCD screen directly, night vision tools is easy to connect with other devices like video cameras. You can store digital vision signals on USB drives, SD devices and many other storage devices. Some devices give you Wi-Fi capability so that you can share images and videos to computers or smartphones.
However, as the digital technology is developing day by day, you can find better images that contains high-resolution displays. Many night vision devices can produce color images instead of green.
Night vision technology applications
This technology is designed to improve viewing in dark. Rifle scopes are popular devices where you might find this technology. So many high-end monoculars and binoculars feature the night vision technology these days.
The main purpose of this technology is to help the military. They can locate the enemy at dark places and target them accurately. Security, police, detectives and investigators often use night vision devices for such purposes as tracking. It is like a blessing to the law enforcement department.
Night vision goggles are another useful source for you to move around in dark places. It is very popular because your hands are free as it is not something to hold but worn. So, you can use your hands for other purposes wearing these goggles.
Another device is the night vision camera that can be used for shooting at dark places or at night. You can also use it if you are night hunting or want to see the wildlife.
