Like many creatures on this planet, we rely heavily on our eyes to interact with our surroundings. However, our vision pales in comparison to many other species. Among animals that rely on sight to survive, falcons have a sharper vision, bees can see more colors, and cats excel in the dark.

What we lack in our bodies, however, can often be compensated for by our ability to make improvements in the human body that equal and sometimes exceed what is available in nature.

Among these advancements, night vision devices (NVDs) have enabled humans to easily integrate into and take advantage of environments that were once only accessible through the use of flashlights and floodlights. Whether it's night vision goggles or binoculars, these devices have brought significant advantages to humanity, first in military combat and more recently in surveillance, security, and rescue operations.

Before becoming such a widely used technology, NVD began as the military's answer tonight warfare. In World War I, large, power-hungry searchlights were used to disperse the darkness and illuminate enemies and allies, which often backfired. By WWII, the first original NVDs, known as generation 0, was developed using lamps with filters that passed only infrared light.

Since infrared is invisible to the human eye, soldiers can easily carry and use image conversion tubes that convert infrared light into the visible spectrum, allowing the user to see only in the desired area. However, this is still a form of active lighting that can be exploited by both sides of the battle, so it is rarely used.

Passive NVDs were not developed and widely used until the Vietnam War. These devices are considered passive because they do not require an external source of infrared illumination but can amplify any reflected light (both infrared and visible) from sources such as the moon and stars. This new technology, labeled the first generation, is significantly more effective at stealth in warfare.

However, the first generation's reliance on ambient light remained problematic on moonless or cloudy nights. By the late 1900s, this problem was addressed and resolved in the second and third generations, both of which focused on using image intensifier tubes (rather than image converter tubes) to amplify very small amounts of light and reliably produce higher resolution images.

Current NVDs consist of five main components in an image intensifier tube: a photocathode, a microchannel plate (MCP), a phosphor screen, and two eyepieces for collecting, magnifying, and focusing images. The first lens captures visible and infrared radiation. Photons of light strike the photocathode, which absorbs the photon's energy and emits electrons with the corresponding energy. These electrons then collide with the MCP, which releases thousands of other electrons with the same energy through a cascade of secondary emissions.

Cascading secondary emission occurs when the original electron collides with the side of the channel and excites atoms along the wall. These excited atoms then release their own electrons, which repeat the process and continue to excite other atoms.

After passing through the MCP, the greatly multiplied electrons eventually collide with a phosphor screen placed at the end of the image intensifier tube. The phosphors are excited by electrons and release photons, which pass through a final lens to produce brightened and magnified images on their way to the human eye. Most of the time, green phosphors are used because humans can distinguish most shades of green, resulting in sharper details.

For the military, NVDs have been refined and specialized for a variety of uses from covert ground operations to aviation, successfully creating more powerful, smaller, lighter, and more versatile devices for our Soldiers.

For flight applications, the NVD must also be adapted to fit on the special headgear required by pilots, taking into account their field of view. Other considerations are their ability to transition from relatively dark to brighter areas when flying over the town, and the goggles' effect on reading important maps and charts at night without having to refocus the lens.

With the successful integration of NVDs into the military flight, civilian pilots in rescue operations, which often fly in darkness and inclement weather to reach their targets, began to use NVDs during their missions. These relatively small additions to flying equipment require hours of training and yield potentially dramatic results, enabling medical pilots to spot their future patients in the dark and reducing the likelihood of a medical helicopter crashing into an already dangerous situation.

Inevitably, the technology has even found its way into luxury cars, with many companies combining the technology to create night vision screens, infrared high beams, and even pedestrian tracking.

These new enhancements can extend the driver's visibility to more than 300 meters at night and during fog and rain, which is a welcome relief from the 50 meters currently offered by regular headlights. It takes about 110 meters to come to a complete stop from a speed of about 100 km/h. These numbers are clearly not good for night driving, but with the incorporation of NVD, this disadvantage is greatly reduced.

However, as with any new technology, adding NVDs to civilian vehicles still requires extensive research and testing. Engineers will need to make sure the extra screen doesn't become another distraction, potentially taking the driver's attention away from the road at a perilous moment.

They also need to avoid creating a false sense of security that causes the driver to relax, or even accelerate, believing that the NVD is infallible. Even experienced emergency pilots need training before flying with such a system, so understandably there may be some reservations when selling such a product, just reading the extra manual.

NVDs are proving to be very versatile today and bring maneuverability in combat, flight, and driving to a new level of safety. Where we once entered blindly into the night, now our armed forces and civilians alike are experiencing the power of engineering to continue to bring light to the dark and beyond the physical limits of the human body. 

As new applications for NVDs continue to be discovered, research in the field is booming, pointing to future advancements such as panoramic and color night vision goggles. In the field of night vision goggles, we have a lot to look forward to.

The above introduces the wide application of night vision devices and the future development trend. If you plan to buy night vision devices, please contact us.

Thermeye is a professional custom thermal camera manufacturer. We have a strong R&D team, professional technical engineers, and a thoughtful service sales department, from product development, sample production, and functional testing to equipment packaging, we are 100% focused on providing products with high satisfaction. Our products are specially developed and produced for different application scenarios. We emphasize product quality, performance, reliability, and make sure everything is safe. Our goal is to make the world a safer place.