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50-656: On 21 September 1987, U.S. forces involved in Operation Prime Chance – the covert part of Operation Earnest Will , the mission to protect U.S.-flagged petroleum -carrying ships in the Persian Gulf – tracked Iran Ajr and dispatched United States Army helicopters from the United States Navy guided-missile frigate USS  Jarrett  (FFG-33) to shadow her. When the aviators reported that people aboard Iran Ajr were laying mines ,

100-483: A micro-channel plate (MCP) with an S-25 photocathode . This produced a much brighter image, especially around the edges of the lens. This led to increased clarity in low ambient-light environments, such as moonless nights . Light amplification was around 20,000 . Image resolution and reliability improved. Examples: Later advances brought GEN II+ devices (equipped with better optics, SUPERGEN tubes, improved resolution and better signal-to-noise ratios ), though

150-443: A 97° FoV. Examples: Foveated night vision (F-NVG) uses specialized WFoV optics to increase the field of view through an intensifier tube. The fovea refers to the part of the retina which is responsible for central vision. These devices have users look "straight through" the tubes so light passing through the center of the tube falls on the foveal retina, as is the case with traditional binocular NVGs. The increased FoV comes at

200-567: A binocular apparatus called 'Design E'. This was bulky, needing an external power pack generating 7,000 volts, but saw limited use with amphibious vehicles of 79th Armoured Division in the 1945 crossing of the Rhine. Between May and June 1943, 43rd (Wessex) Infantry Division trialled man-portable night vision sets, and the British later experimented with mounting the devices to Mark III and Mark II(S) Sten submachine guns. However, by January 1945

250-837: A former radio-guided missile. At that time, infrared was commonly called black light , a term later restricted to ultraviolet . Zworykin's invention was not a success due to its large size and high cost. First-generation passive devices developed by the US Army in the 1960s were introduced during the Vietnam War . They were an adaptation of earlier active technology and relied on ambient light instead of using an extra infrared light source. Using an S-20 photocathode , their image intensifiers amplified light around 1,000 -fold, but they were quite bulky and required moonlight to function properly. Examples: 1970s second-generation devices featured an improved image-intensifier tube using

300-438: A limited field of view (FoV); the commonly used AN/PVS-14 has a FoV of 40, less than the 95° monocular horizontal FoV and humans' 190° binocular horizontal FoV. This forces users to turn their heads to compensate. This is particularly evident when flying, driving, or CQB , which involves split second decisions. These limitations led many SF/SOF operators to prefer white light rather than night vision when conducting CQB. As

350-429: A lower cost. At the higher end, SiOnyx has produced digital color NVGs. The "Opsin" of 2022 has a form factor and helmet weight similar to an AN/PVS-14 , but requires a separate battery pack. It offers a shorter battery life and lower sensitivity. It can however tolerate bright light and process a wider range of wavelengths. Ceramic Optical Ruggedized Engine (CORE) produces higher-performance Gen 1 tubes by replacing

400-608: A protective housing, and an optional mounting system. Many NVDs also include a protective sacrificial lens, mounted over the front/ objective lens to prevent damage by environmental hazards, while some incorporate telescopic lenses . An NVD image is typically monochrome green, as green was considered to be the easiest color to see for prolonged periods in the dark. Night vision devices may be passive, relying solely on ambient light, or may be active, using an IR (infrared) illuminator. Night vision devices may be handheld or attach to helmets . When used with firearms, an IR laser sight

450-608: A range of up to 600 m, had a 30 cm infrared searchlight and an image converter operated by the tank commander. From late 1944 to March 1945 the German military conducted successful tests of FG 1250 sets mounted on Panther Ausf. G tanks (and other variants). During the war, approximately 50 (or 63) Panthers were equipped with the FG 1250 and saw combat on both the Eastern and Western Fronts . The "Vampir" man-portable system for infantry

500-491: A resonance superstructure to orient more of the electric field parallel, so that it can be absorbed. Although cryogenic cooling between 77 K and 85 K is required, QWID technology may be appropriate for continuous surveillance viewing due to its claimed low cost and uniformity in materials. Materials from the II–VI compounds , such as HgCdTe , are used for high-performance infrared light-sensing cameras. An alternative within

550-410: A resonant non-local lithium niobate metasurface with a pump beam. The metasurface boosts the photons' energy, pushing them into the visible spectrum without converting them to electrons. Cooling is not required. Visible and infrared light appear in a single image. Traditionally, night-vision systems capture side-by-side views from each spectrum, so they can't produce identical images. Its frequency range

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600-402: A result, much time and effort has gone into research to develop a wider FoV solution. Panoramic night vision goggles (PNVG) increase FoV by increasing the number of sensor tubes. This solution adds size, weight, power requirements, and complexity. An example is GPNVG-18 (Ground Peripheral Night Vision Goggle). These goggles, and the aviation AN/AVS-10 PNVG from which they were derived, offer

650-713: A steady illumination level in the user's view that improves the ability to keep "eyes on target" in spite of temporary light flashes. These functions are especially useful for pilots, soldiers in urban environments , and special operations forces who may be exposed to rapidly changing light levels. OMNI, or OMNIBUS, refers to a series of contracts through which the US Army purchased GEN III night vision devices. This started with OMNI I, which procured AN/PVS-7A and AN/PVS-7B devices, then continued with OMNI II (1990), OMNI III (1992), OMNI IV (1996), OMNI V (1998), OMNI VI (2002), OMNI VII (2005), OMNI VIII, and OMNI IX. However, OMNI

700-433: A tanker on the very first Earnest Will convoy struck a mine, which made it clear that more forces would be necessary to assure the safety of the civilian vessels. The Joint Chiefs of Staff launched a search for helicopter pilots who could fly at night from navy ships, then set out to train them for the special requirements of the job. Helicopters from the army's 160th Special Operations Aviation Regiment (Airborne) reached

750-417: Is not a specification. The performance of a particular device generally depends upon the tube which is used. For example, a GEN III OMNI III MX-10160A/AVS-6 tube performs similarly to a GEN III OMNI VII MX-10160A/AVS-6 tube, even though the former was manufactured in ~1992 and the latter ~2005. One particular technology, PINNACLE is a proprietary thin-film microchannel plate technology created by ITT that

800-502: Is not enough for practical use. The Sensor and Electron Devices Directorate (SEDD) of the US Army Research Laboratory developed quantum-well infrared detector (QWID). This technology's epitaxial layers use a gallium arsenide (GaAs) or aluminum gallium arsenide system (AlGaAs). It is particularly sensitive to that are mid-length infrared waves. The Corrugated QWIP (CQWIP) broadens detection capacity by using

850-502: Is often mounted to the weapon. The laser sight produces an infrared beam that is visible only through an NVD and aids with aiming. Some night vision devices are made to be mounted to firearms. These can be used in conjunction with weapon sights or standalone; some thermal weapon sights have been designed to provide similar capabilities. These devices were first used for night combat in World War II and came into wide use during

900-407: Is to use an I² device over one eye and a thermal device over the other eye, relying on the human visual system to provide a binocular combined view . Out of Band (OOB) refers to night vision technologies that operate outside the 500-900 nm NIR (near infrared) frequency range. This is possible with dedicated image intensifier tubes or with clip-on devices. Night vision devices typically have

950-522: The III–V family of compounds from InAsSb , a III–V compound, which is common in opto-electronics in items such as DVDs and phones. A graded layer with increased atomic spacing and an intermediate layer of the GaAs substrate trap any potential defects. Metasurface -based upconversion technology provides a night-vision film that weighs less than a gram and can be placed across ordinary glasses. Photons pass through

1000-505: The La Salle detachment transferred to the frigate Jarrett and escorted the convoy to the Gulf of Oman . Soon afterward, operations began from the barges, dubbed Mobile Sea Bases (MSBs). They were set up as naval special warfare task units (NSWTU) run by a SEAL commander and answering to the regional naval special warfare task group. Their mission was to stop Iranian forces from mining

1050-507: The Vietnam War . The technology has evolved since then, involving "generations" of night-vision equipment with performance increases and price reductions. Consequently, though they are commonly used by military and law enforcement agencies, night vision devices are available to civilian users for applications including aviation, driving, and demining . In 1929 Hungarian physicist Kálmán Tihanyi invented an infrared-sensitive electronic television camera for anti-aircraft defense in

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1100-601: The British had only made seven infra-red receiver sets. Although some were sent to India and Australia for trials before the end of 1945, by the Korean War and Malayan Emergency the British were using night vision equipment supplied by the United States. Early examples include: After World War II, Vladimir K. Zworykin developed the first practical commercial night-vision device at Radio Corporation of America , intended for civilian use. Zworykin's idea came from

1150-651: The Iran-Iraq ceasefire began in July 1988. Wimbrown 7 soon returned to port, but Prime Chance patrols continued from Hercules until June 1989. Ships involved in Prime Chance include: Units involved in Prime Chance include: Night vision device A night-vision device (NVD), also known as a night optical/observation device (NOD) or night-vision goggle (NVG), is an optoelectronic device that allows visualization of images in low levels of light, improving

1200-583: The PAU-2 was field-tested in 1942. In 1938 the British Admiralty assumed responsibility for British military infra-red research. They worked first with Philips until the fall of the Netherlands , then with Philips' UK subsidiary Radio Transmission Equipment Ltd., and finally with EMI , who in early 1941 provided compact, lightweight image converter tubes. By July 1942 the British had produced

1250-566: The Persian Gulf or otherwise attacking shipping. Each mobile sea base had two detachments of Mark III patrol boats , a SEAL platoon , an EOD detachment, Marines to provide security, army MH-6 and AH-6 Little Bird helicopter gunships and Black Hawk rescue birds, and air force combat controllers . Mobile Sea Base Hercules was crewed by East Coast naval special warfare units, including Patrol Boats 777 and 758 from Special Boat Unit 20 and Special Boat Unit 24. Mobile Sea Base Wimbrown 7

1300-455: The U.S. commander in the Persian Gulf ordered the pilots to "stop the mining." The helicopters fired on the ship, killing some of the crewmen and chasing others into the water. A team of United States Navy SEAL commandos later boarded the ship, confirmed the presence of mines, and detained the 26 surviving Iranians. Rear Admiral Harold Bernsen said later that the detainees "were given the opportunity to seek political asylum . I think that

1350-642: The UK. Night vision technology prior to the end of World War II was later described as Generation 0. Night-vision devices were introduced in the German Army as early as 1939 and were used in World War II . AEG started developing its first devices in 1935. In mid-1943, the German Army began testing infrared night-vision devices and telescopic rangefinders mounted on Panther tanks . Two arrangements were constructed. The Sperber FG 1250 ("Sparrow Hawk"), with

1400-411: The amount of voltage supplied to the microchannel plate (rather than the photocathode) in response to ambient light. Together, BSP and ABC (alongside autogating) serves to prevent temporary blindness for the user and prevent damage to the tube when the night vision device is exposed to sudden bright sources of light, like a muzzle flash or artificial lighting. These modulation systems also help maintain

1450-404: The devices in a particular OMNI classification. Any postnominals appearing after a generation type (i.e., Gen II+, Gen III+) indicate improvement(s) over the original specification's requirements. Examples: Figure of merit (FoM) is a quantitative measure of a NVD's effectiveness and clarity. It is calculated using the number of line pairs per millimeter that a user can detect multiplied by

1500-611: The fact that the technology itself makes little difference, as long as an operator can see clearly at night. Consequently, the United States bases export regulations directly on the figure of merit. ITAR regulations specify that US-made tubes with a FOM greater than 1400 are not exportable; however, the Defense Technology Security Administration (DTSA) can waive that policy on a case-by-case basis. Fusion night vision combines I² ( image intensification ) with thermal imaging , which functions in

1550-400: The first to use night vision goggles and forward looking infrared devices in combat. Tactics included using MH-6 Little Birds as spotters for the more heavily armed AH-6s for barge-launched missions, and using the warship's radar and that of their SH-60 Seahawk helicopters for the same purpose on ship-launched efforts. Planning and preparation for Prime Chance was launched soon after

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1600-477: The fovea. Examples: Some night vision devices, including several of the ENVG ( AN/PSQ-20 ) models, are "digital". Introduced in the late 2000s, these allow transmission of the image, at the cost of increased size, weight, power usage. High-sensitivity digital camera technology enables NVGs that combine a camera and a display instead of an image intensifier . These devices can offer Gen-1-equivalent quality at

1650-502: The glass plate with a ceramic plate. This plate is produced from specially formulated ceramic and metal alloys. Edge distortion is improved, photo sensitivity is increased, and the resolution can be as high as 60  lp /mm. CORE is still considered Gen 1, as it does not utilize a microchannel plate. A night-vision contact lens prototype places a thin strip of graphene between layers of glass that reacts to photons to brighten dark images. Prototypes absorb only 2.3% of light, which

1700-497: The human eye and peak voltage supplied to the night vision device is maintained. This reduces the " duty cycle " (ie. the amount of time that the tube has power running through it) which increases the device's lifespan. Autogating also enhances the Bright-Source Protection (BSP), which reduces the voltage supplied to the photocathode in response to ambient light levels. Automatic Brightness Control (ABC) modulates

1750-457: The image intensifier's signal-to-noise (SNR) ratio. In the late 1990s, innovations in photocathode technology significantly increased the SNR, with new tubes surpassing Gen 3 performance. By 2001, the United States federal government concluded that a tube's generation was not a determinant performance factor, obsoleting the term as a basis of export regulations. The US government has recognized

1800-414: The ion barrier allowed fewer electrons to pass through. The ion barrier increased the "halo" effect around bright spots or light sources. Light amplification (and power consumption) with these devices improved to around 30,000 – 50,000 . Examples: Autogating (ATG) rapidly switches the power supply's voltage to the photocathode on and off. These switches are rapid enough that they are not detectable to

1850-557: The label is not formally recognized by the NVESD. Third-generation night-vision systems, developed in the late 1980s, maintained the MCP from Gen II, but used a gallium arsenide photocathode, with improved resolution. GA photocathodes are primarily manufactured by L3Harris Technologies and Elbit Systems of America and imaged light from 500-900  nm . In addition, the MCP was coated with an ion barrier film to increase tube life. However,

1900-698: The medium (MWIR 3-5  μm ) and/or long (LWIR 8-14 μm) wavelength range. Initial models appeared in the 2000s. Dedicated fusion devices and clip-on imagers that add a thermal overlay to standard I² night vision devices are available. Fusion combines excellent navigation and fine details (I²), with easy heat signature detection (imaging). Fusion modes include night vision with thermal overlay, night vision only, thermal only, and others such as outline (which outlines objects that have thermal signatures) or "decamouflage", which highlights all objects that are of near-human temperature. Fusion devices are heavier and more power hungry than I²-only devices. One alternative

1950-449: The navy's command ship La Salle in the Persian Gulf on 5 August 1987. The detachment was divided into two teams, with call sign SEABAT and one MH-6 Little Bird, two AH-6s, aircrew, and maintainers. On 8 August, one detachment participated in a convoy escort mission aboard La Salle . The other flew onto the frigate Klakring to protect minesweepers operating in the narrow shipping channel west of Farsi Island . The following day,

2000-411: The northern Persian Gulf . Navy SEALs and explosive ordnance disposal operated from the barges as well. But while Earnest Will was the widely publicized reaction to Kuwaiti pleas for help, Prime Chance was secret. The army helicopters flew at night, slipping to and from navy flight decks under cover of darkness. The helicopter pilots often flew some 30 feet (9.1 m) above the water, and became

2050-412: The price of image quality and edge distortions . Examples: Diverging image tube (DIT) night vision increases FoV by angle the tubes slightly outward. This increases peripheral FoV but causes distortion and reduced image quality. With DIT, users are no longer looking through the center of the tubes (which provides the clearest images) and light passing through the center of the tubes no longer falls on

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2100-570: The retribution campaign of 18 April 1988 called Operation Praying Mantis . The captured colors of Iran Ajr are in the U.S. Navy Museum . Operation Prime Chance Iraqi invasion of Iran (1980) Stalemate (1981) Iranian offensives to free Iranian territory (1981–82) Iranian offensives in Iraq (1982–84) Iranian offensives in Iraq (1985–87) Final stages (1988) Tanker War International incidents Operation Prime Chance (August 1987 – June 1989)

2150-495: The ship in international waters . When the U.S. Navy guided-missile frigate USS  Samuel B. Roberts  (FFG-58) struck a mine in the Persian Gulf in April 1988, U.S. Navy explosive ordnance specialists matched the serial numbers of nearby unexploded mines to the ones aboard Iran Ajr . This evidence of Iranian involvement in the mining of Samuel B. Roberts led to the biggest surface-warfare naval battle since World War II ,

2200-439: The user's night vision . The device enhances ambient visible light and converts near-infrared light into visible light which can then be seen by humans; this is known as I ( image intensification ). By comparison, viewing of infrared thermal radiation is referred to as thermal imaging and operates in a different section of the infrared spectrum. A night vision device usually consists of an image intensifier tube,

2250-491: The vessel and quickly seized it. During the attack, five Iranians were killed and 26 were captured. Several Iranian sailors were rescued from the waters of the Persian Gulf after jumping overboard during the attack. After collecting intelligence data the SEALs and EOD scuttled the vessel the following day. In January 1988, Task Force 118 arrived with OH-58D Kiowa Warrior helicopters. Earnest Will ended about five months after

2300-670: Was a United States Special Operations Command operation intended to protect U.S.-flagged oil tankers from Iranian attack during the Iran–Iraq War . The operation took place roughly at the same time as Operation Earnest Will (July 1987 – September 1988), the largely naval effort to escort the tankers through the Persian Gulf . The operation was begun after the mining of the U.S.-flagged Kuwaiti oil tanker Bridgeton . The two operations were intertwined— United States Army helicopters flew nighttime search-and-destroy missions from Navy frigates and destroyers and from two leased barges in

2350-468: Was crewed by West Coast units, including Patrol Boats 753 and 757 from Special Boat Unit 13 and Patrol Boats 775 and 776 from Special Boat Unit 12. On 21 September 1987, Iran Ajr , an Iranian ship converted for use as a minelayer , was attacked. Using night-vision devices, Army gunship crews watched the Iranian vessel lay several mines, then swooped in firing miniguns and rockets. A SEAL team boarded

2400-578: Was included in the OMNI VII contract. The thin-film improves performance. GEN III OMNI V–IX devices developed in the 2000s and onward can differ from earlier devices in important ways: The consumer market sometimes classifies such systems as Generation 4, and the United States military describes these systems as Generation 3 autogated tubes (GEN III OMNI V-IX). Moreover, as autogating power supplies can be added to any previous generation of night-vision devices, autogating capability does not automatically put

2450-560: Was stated in Washington." Bernsen was "not actually present" when the offers were made by "an officer on my staff," whom he refused to identify. There were no State Department personnel present at the time, he said, but it was within his authority to make the offer in conformity with the policies of the US Department of State . "I think it was done very simply, and very generously." On 26 September, EOD MU5 Detachment 5 scuttled

2500-706: Was used with StG 44 assault rifles. Parallel development occurred in the US. The M1 and M3 infrared night-sighting devices, also known as the "sniperscope" or "snooperscope", saw limited service with the US Army in World War II and in the Korean War , to assist snipers . These were active devices, using an infrared light source to illuminate targets. Their image-intensifier tubes used an anode and an S-1 photocathode , made primarily of silver , cesium , and oxygen , and electrostatic inversion with electron acceleration produced gain. An experimental Soviet device called

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