Penetrating into darkness

Cover Story

Night vision technology and its significance

It is no more a secret that in any future conflict there will be no rest for the soldiers and they will have to keep the operations going even during the nights. An essential component of progressing operations in such a manner is the ability of troops to operate by night.

Today, due to evolution of technology in the form of Night Vision Devices (NVD’s) modern militaries are able to effectively carry the day operations into night. With possibility of having conventional wars as short and precise, the 24-hour battle will be a necessity, forcing systems to be all weather, day and night.

Night vision devices provide enormous benefits. They enable personnel to carry out operations under conditions that would not otherwise be possible.Recent combat deployments in Afghanistan and Iraq in particular, have significantly propelled the case for widespread use of NVDs.

Night vision devices were initially developed for military use, where seeing in the dark is an obvious tactical advantage. However these days this technology is being used for commercial purposes as well. The United States used night vision devices in the Vietnam War and to great effectiveness in the Persian Gulf War. Night vision devices are also used by both urban and rural police forces.

A Night Vision Device (NVD) is an optical instrument that allows images to be produced in levels of light approaching total darkness. They are most often used by the military and law enforcement agencies, but are available to civilian 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 NVDs also include sacrificial lenses, IR 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 their introduction, leading to several “generations” of night vision equipment with performance increasing and price decreasing.

Historically, many armies would not fight at night because the confusion, lack of quality on-time intelligence, and increased communication difficulty made night fighting a very dangerous and very risky proposition. Only the most highly trained soldiers with a well rehearsed plan could take to the battlefield at night with any clear chance of success.

History and Generation

One of the first technologies to enhance vision at night goes all the way back to the end of WWII. The first night vision devices were introduced by the German army as early as 1939.

During World War II, Germans and Americans began developing night vision technology in parallel. One of the first was called the Vampir. This portable night vision device required the soldier to carry a battery pack that energized an infrared searchlight. Infrared light falls outside the visual spectrum for humans, so enemy soldiers could not see the beam but the scope would convert the reflected IR into visible light. All night scopes work on the same principle of shifting the spectrum of incoming light to a frequency that can be seen by the human eye. Because the scope of the Vampir was not sensitive enough to measure ambient light, the searchlight flooded the area with intense IR, making the device an active night scope.

By the end of World War II, the German army had equipped approximately 50 Panther tanks, which saw combat on both the Eastern and Western Fronts. The “Vampir” man-portable system for infantrymen was being used with Sturmgewehr 44 assault rifles.

Parallel development of night vision systems occurred 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, and also used in the Korean War, to assist snipers. They were active devices, using a large infrared light source to illuminate targets. The Vietnam War saw the use of the first passive night vision scopes, using the ambient light to illuminate enemy targets.

The NVDs can be divided into three broad categories in terms of their function and configuration. These are Weapon Sights, Helmet Mounted or Head Mounted Goggles and Handheld or Tripod mounted devices for surveillance. However, based on the technology and performance characteristics they are classified as first, second, third or fourth generation (Gen)-this is also based on the type of tube used.

First generation passive devices, introduced during the Vietnam War, were an adaptation of earlier active GEN 0 technology, and rely on ambient light instead of an infrared light source.

Using an S-20 photocathode, their image intensifiers produce a light amplification of around 1000x, but are quite bulky and require moonlight to function properly.

Second generation devices feature an improved image-intensifier tube utilizing micro-channel plate (MCP) with an S-25 photocathode, resulting in a much brighter image, especially around the edges of the lens.

This leads to increased illumination in low ambient light environments, such as moonless nights.
Later advancements in GEN II technology brought the tactical characteristics of “GEN II+” devices (equipped with better optics, SUPERGEN tubes, improved resolution and better signal-to-noise ratios) into the range of GEN III devices.

An example is the AN/PVS-4 made by Optic Electronic Corporation of Dallas. These devices are still in use in a number of countries. The Gen II-plus NVDs provide better resolution, signal to noise ratio (SNR) and modulation transfer function.

Third generation night vision systems maintain the MCP from Gen II, but now use a photocathode made with gallium arsenide, which further improves image resolution. In addition, the MCP is coated with an ion barrier film for increased tube life. The light amplification is also improved to around 30,000-50,000x.

The AN/PVS-7 night vision goggle is a single tube device with third generation image intensifiers. The AN/ PVS-7 is protected from damage to the image intensifier by exposure to sudden intense light through auto gating – extremely useful in fighting in urban areas especially in counter terrorist operations.

Thousands of these devices are in service and are manufactured by companies like ITT Industries and L3 Communications in the US. These have been extensively used in Gulf War II, Operation Enduring Freedom and Operation Iraqi Freedom.These were subsequently replaced with AN/PVS-14 Monocular Night Vision Device (MNVD). These can also be used in hands free mode by using a head harness or by attaching it to combat helmets.

Further the researchers are now trying to develop fourth generation night vision devices.
In fact, the original night vision for military use was mostly unsuccessful. It was too expensive and exceedingly heavy.

Today, the military still uses night vision devices but they are much better suited to their needs. There are three types of night vision that the military uses: image intensification, active illumination, and thermal imaging. Image intensification essentially works by magnifying the natural light that is available from moonlight, street lights, etc. Active illumination actually uses light that is not detectable by the human eye to light up the images. Finally, thermal imaging is able to show images that give off heat such as human bodies.

There are two main devices that the military uses today in order to take advantage of night vision technologies. The first is night vision goggles which are the less common of the two despite the fact that most soldiers are now equipped with them. Goggles look a bit like binoculars and use image intensification to help users scan for enemies in the dark. The second is simply called a night vision device and it looks more like a telescope. It can be mounted on tanks or even reduced in size and mounted on the sight of a gun or weapon for those on duty in the dark. This is a form of the first devices used in the 1930s and it too uses image intensification.

The military uses night vision for many purposes. Soldiers on the ground use night vision while defending an area or while scanning for opposition. In addition, tanks use night vision devices for the same reason. Generally when using these devices, things appear with a greenish tint because of the way the light reflects off of the landscape. Thermal imaging is used in the military on a larger scale. For example, when looking for enemies in compounds or ensuring there are no civilians in a certain area. Thermal imaging is not only a type of night vision; it can also be used during daylight hours simply to detect the presence of humans.

Future requirement

Most of the armies of the world are now equipped with the third generation NVDs with the fourth generation equipment already in the test and trial phase.

Even BAE Systems is developing state-of-the-art goggles for the US Army that combine night vision and thermal imaging technology.

The Army has awarded the defensc technology specialist a five-year contract worth up to $434 million for the system, which will give soldiers faster and more accurate targeting.  The technology will work in all weather and lighting conditions.

At the moment, military personnel rely on two separate devices-night vision goggles and a weapon-mounted thermal targeting sight. This means that soldiers must acquire targets through their goggles and then raise the weapon sight into their field of view. BAE, however, is integrating night vision and thermal targeting capabilities into a single sight displayed on the soldiers’ goggles. A wireless video interface is used to send thermal images from the weapon sight to the goggles.

The company says that the technology will help military personnel acquire targets and engage enemy combatants faster, and also reduces the need for aiming lasers, enabling soldiers to remain hidden longer.

At present Indian defence services are poorly equipped with the NVDs. The Indian Military specially the Army is presently ill equipped as far as NVDs are concerned. The NVDs held by them are lagging behind in technology and are too few in number.

The Air Force and Navy has a significant and credible capability for night operations. The aircraft carriers and the aircrafts on deck, along with all categories of ships and submarines have the requisite night vision equipment and capability for 24- hours around the clock operations.

Even .The night fighting capability of Special Forces needs to be upgraded on a war footing and can be ignored only at great peril to National Security. Installation of night surveillance devices along international border will facilitate in countering infiltration, smuggling and trans-border crime.

Overall it is expected that during the period 2015-2020, the three Indian armed forces are likely to spend a whopping Rs 23000 crores ($3.6 bn) on electro-optics systems with the NVD segment constituting about Rs 12500 crores ($2 bn) of the total Electro-Optics market.

The demand of Passive Night Vision goggles (PSVGs) is the highest in the market followed by platform optronics, hand held thermals, weapon night sights (WNS), thermal imaging weapon sights, weapon sights, integrated observation equipment and standalone infrared, seismic and acoustic sensors.
So far, India has been able to fulfill most of its requirements for NVDs through imports. As far as indigenous manu­facturing of NVDs is concerned, Bharat Electronics Ltd (BEL) is the biggest supplier of night vision equipment to the Armed Forces but with Gen II technology.

BEL has collaborated with Photonis of France. Photonis Night Vision is a world leader in design and manufacture of image intensifiers. It has provided Supergen technology to BEL a couple of years ago, but the DPSU has failed to utilize it.

Another Indian defence company, Tata Power SED has developed partnership with Harder Digital Gmbh of Germany.

Tata Power SED’s partner, Harder Digital Gmbh had acquired Serbian image intensifier manufacturing company EiSova and is now known as Harder Digital Sova. This company manufactures the complete range of image intensifier tubes from Gen I to Gen III and exports to a number of countries worldwide.

The German government is said to have given clearance to Tata Power SED to import Gen III technology into India as long as the country does not pass it on to others.

Due to the limited indigenous capability, huge gaps remain in the Indian technological potential and the requirement of third generation NVDs. Keeping in mind the old technology second gen NVD’s with the Armed Forces, there definitely exists lucrative opportunities for the Private Sector Companies like Tata Power to tap the present situation-there is therefore an urgent need for the private sector to enter into joint ventures with foreign OEMs, having the requisite expertise in Third Gen NVD technology under the “Make in India” program.

The NVDs are a proven force multiplier and are a requirement for any modern day army. In today’s environment of sub-conventional operations, NVDs are critical for any operations against terrorists who tend to move by night and resort to using terrain for camouflage.

The night vision industry is making itself available to the non-military consumer market. While prices are still high, as demand increases, the price may decrease until the technology is fairly affordable. The technology is already being used by law enforcement and search-and-rescue teams. Night vision technology continues to expand at a rapid pace and more developments in the military will likely be seen in the very near future.