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A U.S. Army soldier uses a helmet mounted vision device during operations in Baghdad, Iraq.
A U.S. Army soldier uses a helmet mounted vision device during operations in Baghdad, Iraq. The United States Army is a military organization whose primary mission is to "provide necessary forces and capabilities. Baghdad (بغداد) is the Capital of Iraq and of Baghdad Governorate, with which it is also coterminous For a topic outline on this subject see List of basic Iraq topics.

A night vision device (NVD) is an optical instrument that allows images to be produced in levels of light approaching total darkness. An optical instrument either processes Light waves to enhance an image for viewing or analyzes light waves (or Photons to determine one of a number of characteristic They are most often used by the military and law enforcement agencies, but are available to civilian users. A military is an Organization authorized by its Nation to use force usually including use of Weapons in defending its Country (or by attacking Police are agents or agencies usually of the executive, empowered to enforce the law and to effect public and social order through the legitimatized use of force A civilian under International humanitarian law is a person who is not a member of his or her Country 's Armed forces. 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. An optical telescope is a Telescope which is used to gather and focus light mainly from the visible part of the Electromagnetic spectrum

NVDs are mounted appropriately for their specific purpose, with more general-purpose devices having more mounting options. For instance, the AN/PVS-14 is a monocular night vision device in use with the US military as well as by civilians. A monocular is a modified Refracting telescope used to Magnify the images of distant objects by passing light through a series of lenses and prisms The United States Armed Forces are the overall unified military forces of the United States It may be mounted on the user's head for handsfree use with a harness or helmet attachment, either as a monocular device, or in aligned pairs for binocular "night vision goggles" which provide a degree of depth perception as do optical binoculars. Handsfree is an adjective describing equipment that can be used without the use of hands (for example via voice commands or in a wider sense equipment which needs only limited use of A helmet is a form of Protective gear worn on the head to protect it from injuries a variation of the hat Binocular telescopes, or binoculars (also known as field glasses are two identical or Mirror - symmetrical telescopes mounted side-by-side and The AN/PVS-14 may also be attached to a rifle using a Picatinny rail, in front of an existing telescopic or red dot sight, or attached to a single-lens reflex camera. A rifle is a Firearm designed to be fired from the shoulder with a barrel that has a helical groove or pattern of grooves ("rifling" cut into the barrel walls The Picatinny rail (ˈpɪkətɪni or /ˌpɪkəˈtɪni/ is a bracket used on some Firearms in order to provide a standardized mounting platform A telescopic sight, commonly called a scope, is a device used to give additional accuracy using a point of aim for Firearms Airguns and Crossbows A red dot sight (also called a reflex sight or for certain models a reflex scope) is a non- magnifying Firearm sight that uses The single-lens reflex (SLR Camera uses an automatic moving mirror system which permits the photographer to see exactly what will be captured by the film or digital imaging [1] Other systems, such as the AN/PVS-22 or Universal Night Sight, are designed for a specific purpose, integrating an image intensifier into, for example, a telescopic sight, resulting in a smaller and lighter but less versatile system. [2]

Night vision devices were first used in World War II, and came into wide use during the Vietnam War. World War II, or the Second World War, (often abbreviated WWII) was a global military conflict which involved a majority of the world's nations, including The Vietnam War, also known as the Second Indochina War, or the Vietnam Conflict, occurred in Vietnam, Laos and Cambodia [3][4] The technology has evolved greatly since their introduction, leading to several "generations" of night vision equipment with performance increasing and price decreasing.

Contents

Usage

Night vision devices were originally developed for military use, but have since spread into other areas, such as security and police work, rescue outfits and various amateur uses (for example animal watching or hunting).

Night vision goggles have been especially praised by the pilots of rescue helicopters, as they eliminate the need for a 'sterile light environment' (i. e. a dark cabin to allow the pilot to let his eyes naturally adjust to night-flying conditions). This will for example allow a medic in the cabin to work on a patient under bright lights while retaining the pilot's ability to fly safely under night conditions. [5]

Function

How night vision works.
How night vision works.

Night vision devices (NVD) work in the near-infrared band at a wavelength of about 1 micrometer. Infrared ( IR) radiation is Electromagnetic radiation whose Wavelength is longer than that of Visible light, but shorter than that of In Physics wavelength is the distance between repeating units of a propagating Wave of a given Frequency. A micrometre ( American spelling: micrometer; symbol µm) is one millionth of a Metre, or equivalently one thousandth of a Millimetre For comparison, the human visual system is sensitive to light wavelengths in the range of about 0. 4 to 0. 7 micrometers. Unlike thermal imaging systems, which operate in complete darkness by detecting heat radiation signatures in infrared wavelengths beyond 3 micrometers, NVDs work in near darkness by detecting ordinary ambient light, usually from the moon and stars, that is reflected by objects in the scene being viewed. wiki stranglesnakejpg|thumb|Thermographic image of a Snake held by a human]] Infrared Thermography, thermal imaging, or thermal video, is a type of Ambient light (also available light or existing light) is a term used by photographers, Cinematographers and other practitioners of the visual A star is a massive luminous ball of plasma. The nearest star to Earth is the Sun, which is the source of most of the Energy on Earth NVDs contain an image intensifier tube that uses the photoelectric effect to amplify very weak light. Introduction When a Metallic surface is exposed to Electromagnetic radiation above a certain threshold Frequency, the light is absorbed and Electrons As each photon of incoming light collides with a detector plate inside the intensifier tube, the plate ejects several electrons that are further amplified into a cascade of electrons. In Physics, the photon is the Elementary particle responsible for electromagnetic phenomena The electron is a fundamental Subatomic particle that was identified and assigned the negative charge in 1897 by J These electrons are accelerated by a strong electric field towards a phosphor screen which emits light at the point of impact of the electrons. A phosphor is a substance that exhibits the phenomenon of Phosphorescence (sustained glowing after exposure to energized particles such as Electrons A bright image is thus formed on the phosphor screen. Outdoor environments that are illuminated only by star light can be easily viewed using night vision devices.

A scene illuminated with a night vision device.
A scene illuminated with a night vision device.

Most night vision devices do not detect color information, and hence a monochromatic phosphor screen is sufficient. Monochrome comes from the Greek μονόχρωμος ( monochromos) meaning “of one color” which is a combination A green phosphor (P22) display is generally used because the human eye is most sensitive to the color green, which falls in the middle of the visible light spectrum. Eyes are organs that detect Light, and send signals along the Optic nerve to the visual areas of the brain [6]

One of the drawbacks of almost all current NVDs is the lack of peripheral vision, meaning that the user needs to turn his head to change his rather narrow field of view. Peripheral vision is a part of vision that occurs outside the very center of gaze [5]

Passive and active

There are two methods of operating night vision systems, passive or active. Passive systems amplify the existing environmental ambient lighting, while active systems rely on an infrared light source to provide sufficient illumination. Early NVDs were designed to be used as active systems, as they did not have the sensitivity to operate on ambient light. Active systems are often used today in closed-circuit television security applications and also on many consumer devices such as home video cameras. Closed-circuit television ( CCTV) is the use of Video cameras to transmit a signal to a specific place limited set of monitors Consumers refers to individuals or households that use goods and services generated within the economy. A video camera is a Camera used for electronic Motion picture acquisition initially developed by the Television industry but now common in other applications

Military applications generally require passive operation, as an active system's infrared illumination device is easily spotted and tracked by others equipped with night vision devices, placing the user at a tactical disadvantage. A military is an Organization authorized by its Nation to use force usually including use of Weapons in defending its Country (or by attacking [7] However, most modern NVG devices include an inbuilt active IR illuminator which can be toggled for use when ambient light is not available.

Active

Active infrared night vision combines infrared illumination of spectral range 700nm-1000nm - just beyond the visible spectrum of the human eye - with special CCD cameras sensitive to this light. The resulting scene, which is apparently dark to a human observer, appears as a monochrome image on a normal display device. [1]

Because active infrared night vision systems can incorporate illuminators that produce high levels of infrared light, the resulting images are typically higher resolution than other night vision technologies[2][3]. Active infrared night vision is now commonly found in commercial, residential and government security applications, where it enables effective night time imaging under low light conditions. However, since active infrared light can be detected by night vision goggles, it is generally not used in tactical military operations.

Passive

Night vision technology, which refers to the quality of the image intensifier tube housed by the NVD, is often classified into "Generations" following the pattern originated by the US Military. The United States Armed Forces are the overall unified military forces of the United States Referring to night vision in terms of its generation is purely for indicative and reference purposes only, even though this has spread to become common consumer terminology. The United States Army class their current in-service devices with the Generation Family Type followed by the device's version or awarded contract. [8] The latest night vision device in service with the United States Army, as of October 2007, is the Gen III Omni VII, manufactured by ITT Corporation. The United States Army is a military organization whose primary mission is to "provide necessary forces and capabilities. ITT Corporation, is a global diversified manufacturing company with 2007 revenues of $9 [9] However, due to the fact that it is an autogated tube, the consumer market generally refers to this as being a 'Gen IV' device.

Within the European Union, Australia, and New Zealand, night vision devices are not referred to in terms of 'Generations', as the most recent image intensifiers in service is the XR5 autogated filmless tube from Photonis-DEP, and hence this product would be considered a ‘Gen IV’ type device by the consumer market. The European Union ( EU) is a political and economic union of twenty-seven member states, located primarily in For a topic outline on this subject see List of basic Australia topics. New Zealand is an Island country in the south-western Pacific Ocean comprising two main landmasses (the North Island and the South Island

Generations

Generation 0

The first night vision devices, 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. World War II, or the Second World War, (often abbreviated WWII) was a global military conflict which involved a majority of the world's nations, including The Korean War refers to a period of military conflict between North Korean and South Korean regimes with major hostilities lasting from June 25 1950 until the READ DISCUSSION PAGE BEFORE MAKING ANY EDITS TO CAPTION BELOW http//en [10] They were active devices, using a large infrared light source to illuminate targets. Their image intensifier tubes function using an anode and an S-1 photocathode, made primarily of silver, caesium, and oxygen to accelerate the electrons. An anode is an Electrode through which Electric current flows into a polarized electrical device A cathode is an Electrode through which (positive Electric current flows out of a polarized electrical device Silver (ˈsɪlvɚ is a Chemical element with the symbol " Ag " (argentum from the Ancient Greek: ἀργήντος - argēntos gen Caesium or cesium (ˈsiːziəm is the Chemical element with the symbol Cs and Atomic number 55 Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the [11] Parallel development of night vision systems by AEG occurred in Nazi Germany, and by the end of World War II, it had equipped approximately 50 Panther tanks, which saw combat on both the Eastern and Western Fronts, and produced the "Vampir" man-portable system for infantry soldiers equipped with Sturmgewehr 44 assault rifles. AEG ( Allgemeine Elektrizitäts-Gesellschaft, General Electricity Company) was a German producer of Electronics and electrical equipment Nazi Germany and the Third Reich are the common English names for Germany under the regime of Adolf Hitler and the National Socialist German Workers The Panther ( was a Tank fielded by Germany in World War II that served from mid-1943 to the end of the European war in 1945 The Eastern Front of World War II (die Ostfront 1941-1945, der Rußlandfeldzug 1941-1945 (Russian campaign or der Ostfeldzug 1941-1945 (Eastern Campaign See Western Front (disambiguation for other meanings Western Front was a term used during the First and Second World The Infantry is the oldest and most numerous of the Combat Arms in the Armed forces, and consists A soldier is a general English term that refers to a member of a land component of National Armed forces. [12]

Generation 1 (GEN I)

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. The Vietnam War, also known as the Second Indochina War, or the Vietnam Conflict, occurred in Vietnam, Laos and Cambodia Using an S-20 photocathode, their image intensifiers produce a light amplification of around 1000x[13], but are quite bulky and require moonlight to function properly. In a Photomultiplier or Phototube, a photocathode is a negatively charged Electrode coated with a Photosensitive compound Moonlight is the light that comes to Earth from the Moon. This light does not originate from the Moon but is actually reflected Sunlight.

Examples:

Generation 2 (GEN II)

Second generation devices featured an improved image-intensifier tube utilizing micro-channel plate (MCP)[14] with an S-25 photocathode[15], resulting in a much brighter image, especially around edges of the lens. A micro-channel plate (MCP is a planar component used for detection of particles ( Electrons or Ions and impinging Radiation ( Ultraviolet This leads to increased illumination in low ambient light environments, such as moonless nights. Light amplification was around 20000x[16] Also improved were image resolution and reliability. Image resolution describes the detail an Image holds The term applies equally to Digital images film images and other types of images

Examples:

Generation 3 (GEN III)

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. Gallium arsenide ( GaAs) is a compound of two elements Gallium and Arsenic. In addition, the MCP is coated with an ion barrier film for increased tube life. The light amplification is also improved, to around 30000-50000x [20]

Examples:

Omnibus-VII

The US Army Night Vision and Electronic Sensors Directorate (NVESD) (http://www.nvl.army.mil/) is part of the governing body that dictates the name of the generation of night vision technologies. Although the recent increased performance associated with the GEN-III OMNI-VII components is impressive, the US Army has not yet authorized the use of the name GEN-IV for these components.

GEN-III OMNI-VII devices can differ from standard Generation 3 in two important ways. First, an automatic gated power supply system regulates the photocathode voltage, allowing the NVD to instantaneously adapt to changing light conditions. Power supply is a reference to a source of Electrical power. A device or system that supplies Electrical or other types of Energy to an output load [24] The second, is a removed or greatly thinned ion barrier, which decreases the amount of electrons that are usually rejected by the Standard GEN III MCP, hence resulting in less image noise and the ability to operate with a luminous sensitivity at 2850K of only 700, compared to operating with a luminous sensitivity of at least 1800 for GEN III type image intensifiers. [25] The disadvantage to a thin or removed ion barrier is the overall decrease in tube life from a theoretical 20,000 hrs mean time to failure (MTTF) for Gen III type, to 15,000 hrs MTTF for GEN IV type. However, this is largely negated by the low numbers of image intensifier tubes that reach 15,000 hrs of operation before replacement.

It is important to note that while the consumer market classifies this type of system as "Generation 4", the United States military describes these systems as Generation 3 Autogated tubes (GEN-III OMNI-VII). Moreover, as autogating power supplies can be now be added to any previous generation of nightvision, 'autogating' capability does not automatically class the devices as a GEN-III OMNI-VII, as seen with the XD-4. Another point to note is that any postnominals appearing after a Generation type (ie: Gen II +, Gen III +) does not change the generation type of the device, but instead indicates a supposed advancement(s) over the original specification's requirements. [26]

Examples:

Other technologies

Panoramic Night Vision Goggles in testing
Panoramic Night Vision Goggles in testing

The US Air Force is experimenting with Panoramic Night Vision Goggles (PNVGs) which double the user's field of view to around 95 degrees by using four 16 mm image intensifiers tubes, rather than the more standard two 18 mm tubes. The field of view (also field of vision) is the angular extent of the observable world that is seen at any given moment They are in service with A-10,MC-130 Combat Talon and AC-130U Spooky aircrews. WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout The Lockheed AC-130 Gunship is a heavily-armed ground attack airplane [29]

IN 2007 Xenonics Holdings, using newly patented technology, offered the first digital night seeing system, a hand held monocule device with 2-8X zoom capability branded Supervision. [30][31]

The PSQ-20, manufactured by ITT seeks to combine thermal imaging with image intensification, as does the Northrop Grumman Fused Multispectral Weapon Sight. wiki stranglesnakejpg|thumb|Thermographic image of a Snake held by a human]] Infrared Thermography, thermal imaging, or thermal video, is a type of [32][33]

Legality

Certain countries (e. g. Hungary and other European Union members) regulate possession of night-vision devices. Hungary (Magyarország 'mɔɟɔrorsaːg) officially in English the Republic of Hungary ( Magyar Köztársaság, literally Magyar (Hungarian Republic The European Union ( EU) is a political and economic union of twenty-seven member states, located primarily in Civilians are allowed to have Generation 1 and Gen1+ devices, but citizen's access to Gen 2 and up is outlawed by adopting International Traffic in Arms Regulations into national legislation. Generation 2 and higher devices are classified as military/law enforcement purpose and espionage tools.

New Zealand rescue helicopter services use several sets of 3rd-generation night vision goggles imported from the USA, and is required to restrict access to the equipment to comply with the strict regulations regarding their export. New Zealand is an Island country in the south-western Pacific Ocean comprising two main landmasses (the North Island and the South Island The United States of America —commonly referred to as the [5]

US Patents

Manufacturers

USA[35][36]

See also

References

  1. ^ PVS-14D night vision monocular goggle
  2. ^ AN/PVS-22 Universal Night Sight
  3. ^ Howstuffworks "Thermal Imaging"
  4. ^ Night Vision & Electronic Sensors Directorate - Fort Belvoir, VA
  5. ^ a b c Seeing in the Dark - Vector, magazine of the Civil Aviation Authority of New Zealand, January/February 2008, Page 10-11
  6. ^ How Night Vision Works: Techniques using Low-light and Infrared imaging
  7. ^ www.nivitech.com / Nightvision Technology / Principles of Nightvision-Devices
  8. ^ How Night Vision Works - Light Amplification Technology - Morovision Night Vision
  9. ^ How Night Vision Works - Light Amplification Technology - Morovision Night Vision
  10. ^ Howstuffworks "Thermal Imaging"
  11. ^ http://www.globalsecurity.org/space/systems/images/night_vision.gif
  12. ^ Achtung Panzer! - German Infrared Night-Vision Devices!
  13. ^ Night Vision Goggles (NVG)
  14. ^ Night Vision Equipment by ATN - FAQ
  15. ^ http://www.globalsecurity.org/space/systems/images/night_vision.gif
  16. ^ Night Vision Goggles (NVG)
  17. ^ AN/PVS-4 Individual Weapon Night Sight
  18. ^ AN/PVS-5 Night Vision Goggles
  19. ^ PHOTONIS.COM - Photons Matter
  20. ^ Night Vision Goggles (NVG)
  21. ^ AN/PVS-7 Night Vision Goggle
  22. ^ AN/PVS-14, MONOCULAR NIGHT VISION DEVICE (MNVD)
  23. ^ PHOTONIS.COM - Photons Matter
  24. ^ \\Baksan\Shared Docs\For Candace\New Folder\LET.tif
  25. ^ www.nivitech.com / Nightvision Technology / Principles of Nightvision Devices
  26. ^ How night vision works - image intensifier technology by ATN
  27. ^ AN/PVS-22 Universal Night Sight
  28. ^ PHOTONIS.COM - Photons Matter
  29. ^ FOUR-EYES: Air Force Spec Ops Get Panoramic Night Vision
  30. ^ Investor Relations, Press
  31. ^ Investor Relations, Press
  32. ^ Defense Tech: Army Optic Combines Heat, Light for Better Sight
  33. ^ Northrop Grumman Delivers First Fused Multispectral Weapon Sight to U.S. Army
  34. ^ Famous Trails® "Night Force" Night Vision Scope w/ 5x Image Magnification: Aiptek Shop
  35. ^ URS Corporation - EG&G - SeaPort
  36. ^ https://www.eggcrane.com/metadot/index.pl?iid=1921
  37. ^ Goodrich Corporation, SUI - Defense-in-depth Strategy for Perimeter Security with SWIR Cameras
  38. ^ http://www.es.northropgrumman.com/nightvision/
  39. ^ Northrop Grumman Delivers First Fused Multispectral Weapon Sight to U.S. Army

External links

ITT Corporation, is a global diversified manufacturing company with 2007 revenues of $9 Northrop Grumman Corporation ( is an Aerospace and defense technology company formed by the 1994 purchase of Grumman by Northrop. Named after inventor Charles Litton Sr, Litton Industries was a large defense contractor in the United States, bought by the Northrop Grumman Corporation Kongsberg Gruppen ( (lit "The Kongsberg Group" is Norway 's major defence contractor and maritime automation supplier located in and named after former mining Raytheon Company ( is a major American Defense contractor and industrial corporation with core Manufacturing concentrations in Defense systems SELEX Sensors and Airborne Systems SpA (SELEX S&AS is a major defence electronics company owned by Finmeccanica. Swarovski is the luxury Brand name for the range of precision-cut Lead crystal Glass and related products produced by companies owned by The Thales Group ( is a French Electronics company delivering mission-critical information systems and services for the Aerospace, Defense Night vision is the ability to see in a dark environment Whether by biological or technological means night vision is made possible by a combination of two approaches sufficient A micro-channel plate (MCP is a planar component used for detection of particles ( Electrons or Ions and impinging Radiation ( Ultraviolet A Daly detector is a gas phase Ion detector that consists of a metal "doorknob" a Scintillator ( Phosphor screen and a Photomultiplier The Civil Aviation Authority of New Zealand (CAA ( Māori: Te Mana Rererangi Tūmatanui o Aotearoa) is the government agency tasked with establishing civil aviation
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