Sales Engineer:Grace Gao
Email:grace@bri-elec.com
WhatsApp:0086-199 2997 5286
Over the past few decades, image intensification technology has gone through multiple stages of development, including 1st, 2nd and 3rd generation image intensification tubes. In this article, I will try to help clear up some confusion about night vision and also try to introduce you to the differences between the generations of night vision devices.
It is always best to start at the beginning, so the most important question to answer is:
Who makes these classifications?
When someone refers to the night vision generations they are not referring to the device itself. Night vision generations refer to the Image Intensifier Tube (IIT) inside the device. The IIT is a tube which amplifies the available ambient lighting conditions by speeding up the electrons of the incoming light (this is a very basic and non-scientific way of explaining how night vision works).
The term ‘generation’ was originally developed for military use in an effort to standardise equipment specifications across nation militaries. These generations have since developed into a common reference point for the quality of night vision devices or “NVD” for military and civilian personnel alike. Through the extensive use in TV Shows and movies, night vision has gained much more attention in the public eye. Benefits are seen within security, military operations, hunting, farming and general use.
Gen 1 Night Vision
Generation 1 NVD’s are the oldest of the night vision technology and has been in use since as early as the 1950’s. Gen 1 tubes do not have a global standard like Gen 2 and Gen 3 which means the quality of tube can vary from device to device. These devices are best suited for short range observation in half moon conditions. They are ideal for the average person who has always wanted to experience the power of night vision.
Within generation 1 tubes you should expect to see imperfections (blemishes) within the tube. These blemishes appear in the form on black dots when you look through the device. In lower light conditions, an Infrared Illuminator may be required to achieve a clear picture and these can either be in-built or standalone torches, depending on your device.
Gen 2 Night Vision
Life Expectancy
Generation 2 NVD’s are a very big leap from generation 1 in both quality and life expectancy. While the average Gen 1 tube is rated to give the user around 1,000 hours of use during its life time, a generation 2 IIT is rated to give the user between 2,500 hours and 5,000 hours. To put 5,000 hours into perspective:
If you used your night vision monocular for 1.5 hours, per day, every single day, you should expect to get 3,333 days of use from that tube. That is over 9 years of extended daily use. It is fair to say most people will not be using their device for 1.5 hours every day of the year. Gen 2 tubes have been known to last well over 10 years if the user takes care of their device.
How The Tube Works
The way that Gen 2 tubes are able to produce such a clearer and brighter image to their gen 1 counter-parts is the addition of the Micro-Channel Plate (MCP). The addition of this MCP has allowed manufacturers of night vision generations 2 devices to offer users a greater range of detection, an image quality closer to Generation 3 than it is to Generation 1 and ability to work in low light conditions at a far higher quality without the need for an IR just to name a few.
Gen 3 Night Vision
Generation 3 NVD’s are the best of the best when it comes to civilian grade night vision. Due to its high price point,
Generation 3 is generally reserved for military, law enforcement and those seeking the best equipment on the market. Gen 3 life expectancy trumps generation 1 and 2 by offering between 7,500 and 10,000 hours of tube life.
The global measure for Generation 3 tube quality is given by the Figure Of Merit (FOM). This is done by multiplying the lp/mm with the Signal To Noise Ratio (SNR). For example:
A tube has a lp/mm of 64 and a SNR of 25
64 lp/mm x 25 SNR = 1600 FOM
Gen 3 devices are much like gen 2 devices in the respect that the quality can vary greatly depending on the specifications. A high quality Gen 3 should give the user an exceptionally clear, crisp and bright image. Gen 3 units will perform the best under low light conditions without the aid of IR. Many models will give the user the option of having an auto-gated or manual gain tube.
To sum up, from the 1st generation to the 3rd generation image intensification tube, great progress has been made in all aspects. We look forward to the image intensifier tube playing an important role in more field applications in the future, bringing people a clearer and more realistic image experience.
Sales Engineer:Grace Gao
Email:grace@bri-elec.com
WhatsApp:0086-199 2997 5286
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