HOW NIGHT VISION WORKS
Night vision devices gather existing ambient light (starlight, moonlight or infra-red light) through their front lenses. This light, made up of photons, goes into a photocathode tube that changes the photons to electrons. The electrons are then amplified to a much greater number through an electrical and chemical process. After that the electrons are hurled against a phosphorus screen that changes the amplified electrons back into visible light that you can see through the eyepiece. The viewed image is a clear green-hued amplified re-creation of the real scene that you are observing through your night vision device. Such scenes are normally invisible or hard discernible to a naked eye, but with assistance of the night vision device you can now see much better and with more details in the dark. Since its development, the night vision industry has been branched into a number of technological levels, called generations.
A Night Vision Device (NVD) can be either of the 1st, 2nd, or 3rd generation. By this is meant the technological level of the image intensifier tube installed to operate in this particular device. The image intensifier tube (or photocathode tube) is the heart and soul of an NVD. From the foregoing figure you have learned the principle of its functioning. Generations vary in specific technological solutions, choice of material and, as a result, in the difference of performance level. The 1st generation is currently the most popular night vision technology in the world. The first generation employs all the basic principles to amplify the existing light several thousand times to let you clearly see in the dark. The 1st generation units provide a bright and sharp image at a low cost, which is perfect, whether you are boating, observing wildlife, or providing security for your home. You may notice the following when you use the 1st generation unit.
NVLC introduces an exclusive CORE image intensifier technology in its brandnew line of Generation 1+ night vision equipment. The latest breakthrough in the electro optical manufacturing engineering has contributed to the development of affordable high performance CORE (Ceramic Optical Ruggedized Engine) Image Intensifier Tubes.
Unlike Gen 1 Image intensifier tubes, fragile by a virtue of being made from glass, CORE IITs are built up just like Gen 2 and Gen 3 by means of fusion of metal alloys with ceramic compounds. The CORE technology has resulted the optimal solution in the production of robust night vision weapon sights for restricted budgets The CORE image intensifier tube will also remain shock-proof against middle-size calibers. Big game hunting and other professional activities become available to many with the affordable CORE night vision technology nowadays. These tubes provide for superior image quality because their photocathodes feature the sensitivity of up to 350 mcA/lm. This is twice as much as the regular Gen 1 photocathodes output. The improved light amplification is backed up with two times increased image resolution - a CORE tube features up to 60 lp/mm resolution; and this performance level makes the CORE tubes peer rival to the existing commercial Gen 2+ image tubes.
This is because the cost of a 2nd gen unit is approximately € 500.00 to €1000.00 more then a 1st gen NVD. The main difference between the 1st and the 2nd generation unit is the addition of a micro-channel plate, commonly referred to as a MCP. The MCP works as an electron amplifier and is placed directly behind the photocathode. The MCP consists of millions of short parallel glass tubes. When the electrons pass through these short tubes, thousands more electrons are released. This extra process allows the 2nd generation units to amplify the light many more times than 1st generation provides, which gives you a brighter and sharper image of the night vision scene, also in the very dark environments.
SDi models stand out for increased technological parameters and spotless tube FOV IITs. In SDi tubes the technologies achieved a higher sensitivity of the photocathode plane that achieves the discrimination of smaller objects in the dark in a way much better than a common Gen 2+ IIT is capable to provide. SDi night vision devices are ideal solutions for demanding sports shooters, big game hunters and nighttime wild nature learners, as well as bodyguard agencies, rescue teams and investigation offices that need powerful tools in the searches and crime prevention activities.
The 3rd generation is the latest technology level in the night vision industry. By adding a more sensitive chemical compound, gallium arsenide (GaAs), to the photocatnode, you get a brighter and sharper image in the end. The GaAs tube“sees” better in the darker environments, and the light amplification for the light gain many times higher than a common Generation 2+ intensifier tube affords (65,000 as compared to the Gen+ gain of 35,000). So that even in the scarcely lit environments you will enjoy a bright image of the viewed scene which your naked eye would see as a common dark dark “nothing”. Consequently, 3rd Gen NVD is by price vastly more expensive than an NVD of the 1st or 2nd generation. Typically a 3rd generation unit bids from € 3,000.00 and more. In the past twenty years such technologies were only available to the armed forces, the navy and the swat teams. Nowadays, they are accessible for civil professional users, too. To enable the Gen HD and Gen 3 tubes working asset in full, we have selected a number of the models of NVD’s that excel in the prime quality materials, versatile and ergonomic design of the body and electronics, and high-precision optical construction. Installed in such NVD models, the HD and Gen 3 tubes deploy their best virtues, relevant to the chosen professional applications. Outstanding Gen QS and Gen 3 night vision monoculars, night vision goggles and night vision binoculars will let you see farther the images of larger depth pitch, also under more adverse viewing conditions or even in the total darkness, and will stay faultlessly on the go for continuous hours of use.
2+ Gen image intensifier tube is a common 2+ generation tube with standard brightness and resolution. Each tube has a micro-channel plate, multi-alkaline photocathode with built-in power supply. Gen 2+ tubes may show few black or bright spots and minor cosmetic imperfections.
SDi Gen 2+ tubes are high quality with exceptional brightness and resolution. The SDi tubes come with raised sensitivity to the infrared spectrum and they are hand picked for additional performance with scarce cosmetics against the standard 2+ IITs.
Devices designed with Improved Definition Image intensifier Tubes are excellent balance between performance and price. Tubes have better resolution (40-50 lp/mm). This IIT has less cosmetic blemishes and better brightness compared to Standard Version.
Gen 2+ IDi night vision video
Night vision devices with Quick Silver Image Intensifier Tubes are the most qualitative devices for most demanding customers. Quick Silver IIT provides clear resolution of 45-54lp/mm, which is the best among 2 Gen Image Intensifier Tubes. This IIT provides black and white screen for enhancing detection and recognition range up to 23 % and cosmetic quality to 15 %.
Gen 2+ QSi night vision video
The Gen 3 image intensifier tubes are the top of the night vision technology currently employed in the professional market. Unlike the Multi-Alkali chemical inside the Gen 2+ tube, The GaAs compound of Gen 3 photocathode plane captures more light energy from the background illumination, so even in the totally darkened room you can still see objects through your Gen 3 NVD.Gen3 IIT Features:
All Starlight scopes need some light to amplify. This means that if you were in complete darkness you could not see. Due to this we have a built in infra-red illuminator (IR) on all of our scopes. Basically what an IR does is throw out a beam of infra-red light that is near invisible to the naked eye but your NVD can see it. This allows you to use your scope even in total darkness. The IR works like a flashlight and the distance you can see with it will be limited. We do use the most powerful eye-safe illuminator on the market. This allows our IRI to extend out to 100 yards However, because of the power at a short distance the IR may cover only 40-60% of the viewing area.
There are many different variables that can effect the distance that you can see with a Night Vision device. First, what are you trying to see? Are you looking for another boat on the water or are you looking for a rabbit in the woods? The larger the object the easier it is too see. Plus, are you trying to see details (what we call recognition range) or are you just trying to see if something is there or maybe you will just see movement but won't be able to 100% determine who or what it is. This is called detection range. Second. Another variable is lighting conditions. The more ambient light you have (starlight, moonlight, infrared light) the better and further you will be able to see You can always see further on a night where the moon and stars are out then if 11 is cloudy and overcast. We typically state that you can tell the difference between a male and a female or a dog and a deer at about 75 to 100 yards. However, if you were looking across an open field and there was a half moon out you could see a barn or a house 500 yards away.
Remember, that the purpose of an NVD is to see in the dark not necessarily a long ways like a binocular.
As you look through a night vision device you may notice black spots on the screen. A NVD is similar to a television screen and attracts dust and dirt. Typically these spots can be cleaned. However, this may also be a spot in the tube itself. This is normal. Most tubes will have some spots in them. These black spots will not affect the performance or reliability of the night vision device.