Night Vision Technology

Explanation of Operating Principles
Night vision devices using image intensifier tube technology require some ambient light to operate. The level of moonlight, starlight or other ambient light necessary is a function of the technology employed. The night vision industry has evolved through three stages, or “Generations” of development. Generation I technology is obsolete in the US market. We offer products based on Generation II, II+, III, and III+. Each generation offers more sensitivity and can operate effectively on less light.

The GEN III Gallium Arsenide (GaAs) photocathode is uniquely sensitive beyond 800 nanometers, considered to be the critical near-infrared region where night sky illuminance levels are greatest. This spectral response shift to the red region results in improved Signal-to-Noise Ratios over GEN III's predecessors, delivering a three-fold improvement in visual acuity and detection distances.

Operating life expectancy of Generation I image intensifier tubes was about 2000 hours. Generation II tubes have a life expectancy from 2,500 hours to 4000 hours. Continuing improvements have increased the operating life expectancy of Generation III tubes to10,000 hours. This makes tube replenishment for the system virtually unnecessary. This is an important consideration when the intensifier tube normally represents 50% of the overall cost of the night vision system. Most natural backgrounds reflect infrared light more readily than visible light. When reflectance differences between discernable objects are maximized, viewing contrast increases, making potential terrain hazards and targets far more distinguishable. Gen III's high infrared response complements this phenomenon, creating a sharper, more informative image.

Generation I

Gain : 1,000x

The early 1960's was witness to the beginning of passive night vision. Technological improvements included vacuum tight fused fiber optics for good center resolution and improved gain, multi-alkali photocathodes and fiber optic input & output windows. GEN I devices lacked the sensitivity and light amplification necessary to see below full moonlight, and were often staged or cascaded to improve gain. As a result, GEN I systems were large and cumbersome, less reliable, and relatively poor low light imagers. They were also characterized by streaking and distortion.

Generation II

Gain : 20,000x

The development of the Microchannel Plate (MCP) led to the birth of Generation II devices in the late 1960's and early 1970's. Higher electron gains were now possible through smaller packaging, and performance improvements made observation possible down to 1/4 moonlight. The first proximity focused microchannel plate (MCP) image intensifier tube was an 18mm used in the original AN/PVS-5 NVG. Generation II+ provides improved performance over standard Gen II by providing increased gain at high and low levels. Generation II+ equipment will provide the best image under full moonlight conditions and is recommended for urban environments.

Generation III

Gain : 30,000 - 50,000x

The current state-of-the-art, the Generation III intensifier multiplies the light gathering power of the eye or video receptor up to 30,000 times. Requiring over 460 manufacturing steps, the GEN III intensifier is typically characterized by a Gallium Arsenide (GaAs) photocathode, which is grown using a metal organic vapor-phase epitaxy (MOVPE) process. The photon sensitivity of the GaAs phtocathode extends into the near-infrared region, where night sky illuminance and contrast ratios are highest. Sealed to an input window which minimizes veiling glare, the photocathode generates an electron current which is proximity focused onto a phosphor screen, where the electron energy is converted into green light which can then be relayed to the eye or sensor through an output window.

IR Illuminator.

All Starlight scopes (image intensification) will need the rest for amplifying light. This means that if you can tretten in full darkness and you see nothing. Therefore, all our devices an infrared illuminator (IRI). IRI casts a beam of infrared light that is invisible for human eyes, but is visible with your night vision device. This allows the use of your night vision device in full darkness. IRI works as a flashlight, so the range is limited.

How far can you see?
There are many different factors that make influence the range of night vision device. First, what you want to see? Find boat On the water or find a rabbit in the woods? The more large the object is, the easier it is to be seen. Plus, you want to see the details) we call the detection range), or they just need to see to see if there is something, or perhaps just moving and not 100% who or what that is. It is within easy reach. Secondly, another condition is the lighting. The more rest you have light (moon light, IR)-light or light from the stars, the better and farther you can see. They are always on and can see better at night when there are the moon and the stars, as if it clouds wäre.Wir but always say that you will recognize the man or woman, dog or deer ca 75 to 100 meters away . But if you are in an open field and it is Haldmond, you can also see a house or building, to around 500 meters. Please note that the purpose of a night vision device - see in the dark, and not on the longer distances, such as Binoculars.

When looking through a night vision device, you can see small black dots on the screen surface. A night vision device works similar to the television itself and attracts dust. Typically, these points can be removed. But it can also strengthen the points in the light pipes, this is normal. Most pipes have such points. These points do not affect the reality of the image.