Night vision technology can be broken down into three general categories. Image intensification, active illumination and thermal imaging. Image intensification intensifies any ambient light allowing you to clearly see images in extremely low light conditions. Active illumination combines image intensification technology with a source of illumination that is in the near infrared light spectrum. Thermal imaging technology is able to “see” light in the infrared spectrum that is invisible to the naked eye. Thermal imaging devices can detect temperature differences allowing the user to see warm objects in total darkness.
Active illumination and thermal imaging devices are very expensive and these devices are usually cameras that show what they are “seeing” on a screen. When it comes to night vision binoculars the technology available will almost always be image intensification or light amplification technology. This type of technology gathers ambient light and uses a photocathode as an image intensifier that greatly amplifies even the smallest amount of ambient light.
The very first night vision devices were used by the German army in World War II. Since then there have been a lot of improvements to the technology and there are now different “generations” of the image intensification night vision devices. The first night vision devices are designated as generation 0 devices. These early night vision devices were “active” devices that required infrared illumination to be effective.
Generation 1 devices were introduced during the Vietnam War and improved upon generation 0 technology. These devices did not need an active source of illumination and relied only on ambient light. They were large and somewhat bulky and required moonlight to function properly but they were able to amplify the ambient light up to 1,000 times.
Generation 2 devices improved further and are able to operate in even lower light situations such as a moonless night. These devices are able to amplify ambient light up to 20,000 times and also have improved image resolution.
Generation 3 devices use an improved photocathode which improves image resolution even further and these devices are able to amplify ambient light approximately 30,000 to 50,000 times.
The next generation of night vision devices are referred to as Generation 4 by civilians and the consumer market but the US military describes these systems as Generation 3 Autogated tubes or GEN-III OMNI-VII. This next generation of night vision devices uses an automatic gated power supply to regulate the voltage of the photocathode, allowing the devices to automatically and instantaneously adapt to changing light conditions. These newer devices also offer cleaner images with less noise.
Many of the night vision binoculars that are available today use Generation 1 or Generation 2 light amplification technology. The prices and the quality of night vision binoculars vary considerably so if you are in the market for a pair it would be well worth your time to do some research to make sure you get a pair of binoculars that has the features you’re looking for at a price that you are willing to pay. A good pair of night vision binoculars can cost anywhere from a few hundred to a few thousand dollars so any time spent researching your various options is time well spent.