Latest News

The History of Night Vision Technology

nyx-7 outdoor

Night Vision technology has developed so much in recent years, that it is hard to believe that it originates from before the Second World War. In this article we explore the history of Night Vision, and the generational changes that have lead us here.

gen 0 night vision device
Gen 0 Night Vision

A Night Vision Device is an optical instrument that allows images to be produced in near total darkness. They are most often used by the military and law enforcement agencies, but are readily available to private users.

The term usually refers to a complete unit, including an image intensifier tube, a protective and generally water-resistant housing, and some type of mounting system. Many also include sacrificial lenses, infrared illuminators, and telescopic lenses.

Night vision devices were first used in World War II, and came into wide use during the Vietnam War. The technology has evolved greatly since. Each succession of newer night optics are called ‘generations’ with performance increasing and prices decreasing at each interval.

Historically armies did not fight at night because of the confusion, lack of intel, and increased difficulty with communication. Only the most highly trained soldiers with a well-rehearsed plan could take to the battlefield at night with any chance of success.

Vampir night vision system
The ‘Vampir’

The first night vision devices (Gen 0) were introduced by the German army as early as 1939. By the end of World War II, the German army had equipped approximately 50 Panther tanks with night optics. Infantry were being equipped with the “Vampir” man-portable system that mounted to Sturmgewehr 44 assault rifles.

Parallel development of night vision was occurring in the United States. The M1 and M3 infrared night sighting devices, also known as the “sniperscope” or “snooperscope”, were introduced by the US Army in World War II. They were active devices, using a large infrared light source to illuminate targets for snipers.

First generation passive devices, introduced during the Vietnam War, were an adaptation of earlier active Gen 0 technologies. They relied on ambient light instead of an active infrared light source. These devices had image intensifiers that produced a light amplification of around 1000x, but were quite bulky and largely impractical.

m2 sniperscope night vision device
M2 Sniperscope

Second generation devices featured an improved image-intensifier tube, which utilized a micro-channel plate with an S-25 photocathode. This combination resulted in a much brighter image especially around the edges of the lens. There was also a much needed increase of illumination in low ambient light environments, such as moonless nights. Light amplification was around 20,000x, and image resolution and reliability were also profoundly improved.

Later advancements in technology lead to the development of ‘Gen II+’ devices. These devices were equipped with better optics, supergen tubes, improved resolution and better signal-to-noise ratios.

Third generation night vision systems still use the micro-channel plate developed in the second generation, but now use a different photocathode. The new cathode uses gallium arsenide which improves image resolution and aids in the 30,000-50,000x light amplification. The MCP, in Gen III designs, is coated with an ion barrier film that increases tube life but can impede photoelectrons from entering the plate. The result is that some Gen III devices can produce higher levels of electronic noise than their Gen II counterparts.

The improvements in night optics in the last decade have been immense. Drastic technological advancements have meant clearer images, improved light amplification, and unbelievable leaps forward for durability and portability. With such a rich history of development, the future for night vision devices is looking bright.

 

If you would like to see more articles like this one, subscribe to our newsletter here! Special thanks to Armasight for their Night Vision Academy lesson and resources.

What Makes A Good Thermal Monocular?

Scout TK Thermal Monocular

Thermal Monoculars are fast becoming the most popular night optic on the market. Within the past decade the thermal monocular has very closely followed the mobile phone in terms of development.

The units have been developed with higher specifications and more functional features. The design has become more compact and durable and the overall quality has risen substantially. The major area in which the two technologies differ is price. While mobile phone technology has climbed in price thermal imaging has dropped, bringing thermal into the realm of the affordable personal device.

So what makes a good thermal monocular?

 

Microbolometer

Elephant Thermal Image

The microbolometer is the sensor inside the unit which detects temperature patterns. The resolution of this sensor is measured in pixels. Like a TV the higher the amount of pixels, the greater the level of detail you will see.

The FLIR Scout III 640, for example, has a resolution of 640 pixels x 512 pixels with a grand total of 327 680 pixels. The American made unit uses the Tau2 core and is the top of the range for hunters, and outdoor enthusiasts. The high resolution allows the Scout III 640 to gain an extremely detailed image day or night.

 

Refresh Rate

In basic terms, the refresh rate of a thermal monocular is the frequency at which the image is refreshed on screen. This rate is expressed in ‘Hertz’ with common refresh rates around 9Hz, 30Hz, 50Hz and 60Hz. The higher the ‘Hertz’, the more often the image is refreshed.

If you are looking for a recreational camera (such as the FLIR Scout TK) to use to explore the outdoors, track down game or just have fun with, then 9Hz will be all you need. Without the need to scan or change views quickly, a lower refresh rate is more than suitable. However, when it comes to higher quality models, the refresh rate becomes increasingly important for the user’s experience. We recommend 30Hz or higher for anything above amateur use, such as contract shooting or professional hunting.

Scout Thermal Monocular Hunting

Lens Size

The lens of a thermal monocular plays a major in role determining the maximum detection distance of a thermal monocular. Detection distances can vary between 90 meters to over 1.5km! Lens sizes can vary from 9mm up to 100mm and the general rule of thumb is ‘Bigger is Better’.

While the lens being larger may increase the detection distance of the unit, it also narrows the Field of View (FOV). For example a 38mm lens will give you a FOV of 19.5’ x 14.7’ while a 50mm lens cuts FOV down to 7.5’ x 5.6’. With this in mind it is important to select a monocular that not only gives you an adequate detection distance, but also suits your needs in terms of Field of View.

It is also important to consider the image quality versus distance offered by lens sizes and sensor resolution. It is important to consider what is right for your personal applications and make an informed decision.

 

Turkey and Ostrich Thermal Image

Durability, Reputation & Warranty

Not all thermal monoculars are created equal. Although the cost of the units has come down significantly over the last few years, they are still a sizable investment. It is important to choose a unit that will not only give you excellent picture quality, but is also durable and reliable.

A thermal camera should still be fully functional 10+ years after purchase date as long as it is properly cared for. Many manufacturers claim long life, but be sure to shop around for products with substantial warranties. FLIR, for example, offer a 10 year warranty on the sensor in all their thermal imaging devices.

The reputation of a manufacturer is also important when purchasing a thermal monocular. There are a few things to consider about a brand before making a purchase:

  • Do they honor their warranty policy?
  • Do they have a Distributor in Australia as a point of contact?
  • Is the warranty global or limited to the country of purchase?

 

I hope that this brief guide has been able to help you get a better understanding of what makes a good thermal monocular. Make sure to keep learning about night optics through our articles such as Gen 1, Gen 2 & Gen 3 Night Vision: What Is The Difference?

As always, please feel free to leave any questions or comments below or contact us directly via email or phone!

Gen 1, Gen 2 & Gen 3 Night Vision: What Is The Difference?

One of the most common questions we get at Night Vision Australia is “What is the difference between night vision generations?”

In this article I will try and help clear up some of the confusion surrounding night vision. We will also try and educate you a little bit regarding the differences in night vision generations.

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 standardize 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 (there was generation 0 but we won’t go into that) 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. Devices generally start from $350 for a monocular and range from $500-$1000 for night vision goggles.

 

 

 

 

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 fairto 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.

One thing you should be aware of before diving into buying a Gen 2 is that not all Gen 2 tubes are rated the same. Just like a car with a standard, sports and pro model line, NVD’s offer differing quality of tube which all still fall under the umbrella ‘Generation 2’.

 

An Example

Lets take the Armasight By FLIR NYX-7 Night Vision Goggles as an example. This unit comes with 4 different quality IIT’s but the housing is near identical. The major difference between the models is the lp/mm offered by the tube inside the device. Lp/mm stands for line pairs per millimeter and essentially refers to the resolution/quality of the image you will see. For example the Standard Definition (SD) model has a lp/mm of 45-51. This is compared with the High Definition (HD) model boasts a huge 55-72 lp/mm. As you can see there is a massive difference in lp/mm within the same product line, which in turn gives varying performance qualities.

TIP: If you are looking to buy a gen 2 night vision device and the seller can’t tell you the lp/mm, approach the deal very carefully. As seen above since there is such a huge gap between ‘entry level’ gen 2 and ‘high end’ gen 2 it is very difficult to gauge the quality and value of the device without all of the information.

 

 

 

 

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 (See: Auto-gated VS Manual Gain).

It is worth noting that while generation 3 devices are legal for use in Australia, some countries (such as the USA) have export restrictions on high end and military style equipment. If you want to know more about night vision and the law have a read of ‘Is Night Vision Legal In Australia?’. follow this link

 

While this is by no means an extensive explanation of the differences between all of the night vision generations I am hoping it has helped your night vision education process.

If you have any questions, Please feel free to ask. Our experienced team at Night Vision Australia based in Sydney, Australia are always more than happy to assist.